Search Results

Search found 56999 results on 2280 pages for 'object oriented database'.

Page 105/2280 | < Previous Page | 101 102 103 104 105 106 107 108 109 110 111 112  | Next Page >

• Confusion about inheritance

  - by Samuel Adam

  I know I might get downvoted for this, but I'm really curious. I was taught that inheritance is a very powerful polymorphism tool, but I can't seem to use it well in real cases. So far, I can only use inheritance when the base class is an abstract class. Examples : If we're talking about Product and Inventory, I quickly assumed that a Product is an Inventory because a Product must be inventorized as well. But a problem occured when user wanted to sell their Inventory item. It just doesn't seem to be right to change an Inventory object to it's subtype (Product), it's almost like trying to convert a parent to it's child. Another case is Customer and Member. It is logical (at least for me) to think that a Member is a Customer with some more privileges. Same problem occurred when user wanted to upgrade an existing Customer to become a Member. A very trivial case is the Employee case. Where Manager, Clerk, etc can be derived from Employee. Still, the same upgrading issue. I tried to use composition instead for some cases, but I really wanted to know if I'm missing something for inheritance solution here. My composition solution for those cases : Create a reference of Inventory inside a Product. Here I'm making an assumption about that Product and Inventory is talking in a different context. While Product is in the context of sales (price, volume, discount, etc), Inventory is in the context of physical management (stock, movement, etc). Make a reference of Membership instead inside Customer class instead of previous inheritance solution. Therefor upgrading a Customer is only about instantiating the Customer's Membership property. This example is keep being taught in basic programming classes, but I think it's more proper to have those Manager, Clerk, etc derived from an abstract Role class and make it a property in Employee. I found it difficult to find an example of a concrete class deriving from another concrete class. Is there any inheritance solution in which I can solve those cases? Being new in this OOP thing, I really really need a guidance. Thanks!

  Read the article

• But what version is the database now?

  - by BuckWoody

  When you upgrade your system to SQL Server 2008 R2, you’ll know that the instance is at that version by using the standard commands like SELECT @@VERSION or EXEC xp_msver. My system came back with this info when I typed those: Microsoft SQL Server 2008 R2 (RTM) - 10.50.1600.1 (Intel X86)   Apr  2 2010 15:53:02   Copyright (c) Microsoft Corporation  Developer Edition on Windows NT 6.0 <X86> (Build 6002: Service Pack 2) (Hypervisor) Index Name Internal_Value Character_Value 1 ProductName NULL Microsoft SQL Server 2 ProductVersion 655410 10.50.1600.1 3 Language 1033 English (United States) 4 Platform NULL NT INTEL X86 5 Comments NULL SQL 6 CompanyName NULL Microsoft Corporation 7 FileDescription NULL SQL Server Windows NT 8 FileVersion NULL 2009.0100.1600.01 ((KJ_RTM).100402-1540 ) 9 InternalName NULL SQLSERVR 10 LegalCopyright NULL Microsoft Corp. All rights reserved. 11 LegalTrademarks NULL Microsoft SQL Server is a registered trademark of Microsoft Corporation. 12 OriginalFilename NULL SQLSERVR.EXE 13 PrivateBuild NULL NULL 14 SpecialBuild 104857601 NULL 15 WindowsVersion 393347078 6.0 (6002) 16 ProcessorCount 1 1 17 ProcessorActiveMask 1 1 18 ProcessorType 586 PROCESSOR_INTEL_PENTIUM 19 PhysicalMemory 2047 2047 (2146934784) 20 Product ID NULL NULL   But a database properties are separate from the Instance. After an upgrade, you always want to make sure that the compatibility options (which have much to do with how NULLs and other objects are treated) is at what you expect. For the most part, as long as the application can handle it, I set my compatibility levels to the latest version. For SQL Server 2008, that was “10.0” or “10”. You can do this with the ALTER DATABASE command or you can just right-click the database and select “Properties” and then “Database Options” in SQL Server Management Studio. To check the database compatibility level, I use this query: SELECT name, cmptlevel FROM sys.sysdatabases When I did that this morning I saw that the databases (all of them) were at 10.0 – not 10.5 like the Instance. That’s expected – we didn’t revise the database format up with the Instance for this particular release. Didn’t want to catch you by surprise on that. While your databases should be at the “proper” level for your situation, you can’t rely on the compatibility level to indicate the Instance level. More info on the ALTER DATABASE command in SQL Server 2008 R2 is here: http://technet.microsoft.com/en-us/library/bb510680(SQL.105).aspx Share this post: email it! | bookmark it! | digg it! | reddit! | kick it! | live it!

  Read the article

• PHP - Internal APIs/Libraries - What makes sense?

  - by Mark Locker

  I've been having a discussion lately with some colleagues about the best way to approach a new project, and thought it'd be interesting to get some external thoughts thrown into the mix. Basically, we're redeveloping a fairly large site (written in PHP) and have differing opinions on how the platform should be setup. Requirements: The platform will need to support multiple internal websites, as well as external (non-PHP) projects which at the moment consist of a mobile app and a toolbar. We have no plans/need in the foreseeable future to open up an API externally (for use in products other than our own). My opinion: We should have a library of well documented native model classes which can be shared between projects. These models will represent everything in our database and can take advantage of object orientated features such as inheritance, traits, magic methods, etc. etc. As well as employing ORM. We can then add an API layer on top of these models which can basically accept requests and route them to the appropriate methods, translating the response so that it can be used platform independently. This routing for each method can be setup as and when it's required. Their opinion: We should have a single HTTP API which is used by all projects (internal PHP ones or otherwise). My thoughts: To me, there are a number of issues with using the sole HTTP API approach: It will be very expensive performance wise. One page request will result in several additional http requests (which although local, are still ones that Apache will need to handle). You'll lose all of the best features PHP has for OO development. From simple inheritance, to employing the likes of ORM which can save you writing a lot of code. For internal projects, the actual process makes me cringe. To get a users name, for example, a request would go out of our box, over the LAN, back in, then run through a script which calls a method, JSON encodes the output and feeds that back. That would then need to be JSON decoded, and be presented as an array ready to use. Working with arrays, as appose to objects, makes me sad in a modern PHP framework. Their thoughts (and my responses): Having one method of doing thing keeps things simple. - You'd only do things differently if you were using a different language anyway. It will become robust. - Seeing as the API will run off the library of models, I think my option would be just as robust. What do you think? I'd be really interested to hear the thoughts of others on this, especially as opinions on both sides are not founded on any past experience.

  Read the article

• Does OO, TDD, and Refactoring to Smaller Functions affect Speed of Code?

  - by Dennis

  In Computer Science field, I have noticed a notable shift in thinking when it comes to programming. The advice as it stands now is write smaller, more testable code refactor existing code into smaller and smaller chunks of code until most of your methods/functions are just a few lines long write functions that only do one thing (which makes them smaller again) This is a change compared to the "old" or "bad" code practices where you have methods spanning 2500 lines, and big classes doing everything. My question is this: when it call comes down to machine code, to 1s and 0s, to assembly instructions, should I be at all concerned that my class-separated code with variety of small-to-tiny functions generates too much extra overhead? While I am not exactly familiar with how OO code and function calls are handled in ASM in the end, I do have some idea. I assume that each extra function call, object call, or include call (in some languages), generate an extra set of instructions, thereby increasing code's volume and adding various overhead, without adding actual "useful" code. I also imagine that good optimizations can be done to ASM before it is actually ran on the hardware, but that optimization can only do so much too. Hence, my question -- how much overhead (in space and speed) does well-separated code (split up across hundreds of files, classes, and methods) actually introduce compared to having "one big method that contains everything", due to this overhead? UPDATE for clarity: I am assuming that adding more and more functions and more and more objects and classes in a code will result in more and more parameter passing between smaller code pieces. It was said somewhere (quote TBD) that up to 70% of all code is made up of ASM's MOV instruction - loading CPU registers with proper variables, not the actual computation being done. In my case, you load up CPU's time with PUSH/POP instructions to provide linkage and parameter passing between various pieces of code. The smaller you make your pieces of code, the more overhead "linkage" is required. I am concerned that this linkage adds to software bloat and slow-down and I am wondering if I should be concerned about this, and how much, if any at all, because current and future generations of programmers who are building software for the next century, will have to live with and consume software built using these practices. UPDATE: Multiple files I am writing new code now that is slowly replacing old code. In particular I've noted that one of the old classes was a ~3000 line file (as mentioned earlier). Now it is becoming a set of 15-20 files located across various directories, including test files and not including PHP framework I am using to bind some things together. More files are coming as well. When it comes to disk I/O, loading multiple files is slower than loading one large file. Of course not all files are loaded, they are loaded as needed, and disk caching and memory caching options exist, and yet still I believe that loading multiple files takes more processing than loading a single file into memory. I am adding that to my concern.

  Read the article

• Advantage database throws an exception when attempting to delete a record with a like statement used

  - by ChrisR

  The code below shows that a record is deleted when the sql statement is: select * from test where qty between 50 and 59 but the sql statement: select * from test where partno like 'PART/005%' throws the exception: Advantage.Data.Provider.AdsException: Error 5072: Action requires read-write access to the table How can you reliably delete a record with a where clause applied? Note: I'm using Advantage Database v9.10.1.9, VS2008, .Net Framework 3.5 and WinXP 32 bit using System.IO; using Advantage.Data.Provider; using AdvantageClientEngine; using NUnit.Framework; namespace NetworkEidetics.Core.Tests.Dbf { [TestFixture] public class AdvantageDatabaseTests { private const string DefaultConnectionString = @"data source={0};ServerType=local;TableType=ADS_CDX;LockMode=COMPATIBLE;TrimTrailingSpaces=TRUE;ShowDeleted=FALSE"; private const string TestFilesDirectory = "./TestFiles"; [SetUp] public void Setup() { const string createSql = @"CREATE TABLE [{0}] (ITEM_NO char(4), PARTNO char(20), QTY numeric(6,0), QUOTE numeric(12,4)) "; const string insertSql = @"INSERT INTO [{0}] (ITEM_NO, PARTNO, QTY, QUOTE) VALUES('{1}', '{2}', {3}, {4})"; const string filename = "test.dbf"; var connectionString = string.Format(DefaultConnectionString, TestFilesDirectory); using (var connection = new AdsConnection(connectionString)) { connection.Open(); using (var transaction = connection.BeginTransaction()) { using (var command = connection.CreateCommand()) { command.CommandText = string.Format(createSql, filename); command.Transaction = transaction; command.ExecuteNonQuery(); } transaction.Commit(); } using (var transaction = connection.BeginTransaction()) { for (var i = 0; i < 1000; ++i) { using (var command = connection.CreateCommand()) { var itemNo = string.Format("{0}", i); var partNumber = string.Format("PART/{0:d4}", i); var quantity = i; var quote = i * 10; command.CommandText = string.Format(insertSql, filename, itemNo, partNumber, quantity, quote); command.Transaction = transaction; command.ExecuteNonQuery(); } } transaction.Commit(); } connection.Close(); } } [TearDown] public void TearDown() { File.Delete("./TestFiles/test.dbf"); } [Test] public void CanDeleteRecord() { const string sqlStatement = @"select * from test"; Assert.AreEqual(1000, GetRecordCount(sqlStatement)); DeleteRecord(sqlStatement, 3); Assert.AreEqual(999, GetRecordCount(sqlStatement)); } [Test] public void CanDeleteRecordBetween() { const string sqlStatement = @"select * from test where qty between 50 and 59"; Assert.AreEqual(10, GetRecordCount(sqlStatement)); DeleteRecord(sqlStatement, 3); Assert.AreEqual(9, GetRecordCount(sqlStatement)); } [Test] public void CanDeleteRecordWithLike() { const string sqlStatement = @"select * from test where partno like 'PART/005%'"; Assert.AreEqual(10, GetRecordCount(sqlStatement)); DeleteRecord(sqlStatement, 3); Assert.AreEqual(9, GetRecordCount(sqlStatement)); } public int GetRecordCount(string sqlStatement) { var connectionString = string.Format(DefaultConnectionString, TestFilesDirectory); using (var connection = new AdsConnection(connectionString)) { connection.Open(); using (var command = connection.CreateCommand()) { command.CommandText = sqlStatement; var reader = command.ExecuteExtendedReader(); return reader.GetRecordCount(AdsExtendedReader.FilterOption.RespectFilters); } } } public void DeleteRecord(string sqlStatement, int rowIndex) { var connectionString = string.Format(DefaultConnectionString, TestFilesDirectory); using (var connection = new AdsConnection(connectionString)) { connection.Open(); using (var command = connection.CreateCommand()) { command.CommandText = sqlStatement; var reader = command.ExecuteExtendedReader(); reader.GotoBOF(); reader.Read(); if (rowIndex != 0) { ACE.AdsSkip(reader.AdsActiveHandle, rowIndex); } reader.DeleteRecord(); } connection.Close(); } } } }

  Read the article

• Associating an Object with other Objects and Properties of those Objects

  - by alzoid

  I am looking for some help with designing some functionality in my application. I already have something similar designed but this problem is a little different. Background: In my application we have different Modules. Data in each module can be associated to other modules. Each Module is represented by an Object in our application. Module 1 can be associated with Module 2 and Module 3. Currently I use a factory to provide the proper DAO for getting and saving this data. It looks something like this: class Module1Factory { public static Module1BridgeDAO createModule1BridgeDAO(int moduleid) { switch (moduleId) { case Module.Module2Id: return new Module1_Module2DAO(); case Module.Module3Id: return new Module1_Module3DAO(); default: return null; } } } Module1_Module2 and Module1_Module3 implement the same BridgeModule interface. In the database I have a Table for every module (Module1, Module2, Module3). I also have a bridge table for each module (they are many to many) Module1_Module2, Module1_Module3 etc. The DAO basically handles all code needed to manage the association and retrieve its own instance data for the calling module. Now when we add new modules that associate with Module1 we simply implement the ModuleBridge interface and provide the common functionality. New Development We are adding a new module that will have the ability to be associated with other Modules as well as specific properties of that module. The module is basically providing the user the ability to add their custom forms to our other modules. That way they can collect additional information along with what we provide. I want to start associating my Form module with other modules and their properties. Ie if Module1 has a property Category, I want to associate an instance From data with that property. There are many Forms. If a users creates an instance of Module2, they may always want to also have certain form(s) attached to that Module2 instance. If they create an instance of Module2 and select Category 1, then I may want additional Form(s) created. I prototyped something like this: Form FormLayout (contains the labels and gui controls) FormModule (associates a form with all instances of a module) Form Instance (create an instance of a form to be filled out) As I thought about it I was thinking about making a new FormModule table/class/dao for each Module and Property that I add. So I might have: FormModule1 FormModule1Property1 FormModule1Property2 FormModule1Property3 FormModule1Property4 FormModule2 FormModule3 FormModule3Property1 Then as I did previously, I would use a factory to get the proper DAO for dealing with all of these. I would hand it an array of ids representing different modules and properties and it would return all of the DAOs that I need to call getForms(). Which in turn would return all of the forms for that particular bridge. Some points This will be for a new module so I dont need to expand on the factory code I provided. I just wanted to show an example of what I have done in the past. The new module can be associated with: Other Modules (ie globally for any instance of that module data), Other module properties (ie only if the Module instance has a certian value in one of its properties) I want to make it easy for developers to add associations with other modules and properties easily Can any one suggest any design patterns or strategy's for achieving this? If anything is unclear please let me know. Thank you, Al

  Read the article

• The World of SQL Database Deployment

  - by GGBlogger

  In my early development days, I used Microsoft Access for building databases. It made things easy since I only needed to package the database with the installation package so my clients would have access to it. When we began the development of a new package in Visual Studio .NET I decided to use SQL Server Express. It was free and provided good tools - also free. I thought it was a tremendous idea until it came time to distribute our new software! What a surprise. The nightmare Ah, the choices! Detach the database and have the client reattach it to a newly installed – oh wait. FIRST my new client needs to download and install SQL Server Express with SQL Server Management Studio. That’s not a great thing, but it is one more nightmare step for users who may have other versions of SQL installed. Then the question became – do we detach and reattach or do we do a backup. It was too late (bad planning) to revert to Microsoft Access but we badly needed a simple way to package and distribute both the database AND sample contents. Red Gate to the rescue It took me a while to find an answer but I did find it in a package called SQL Packager sold by a relatively unpublicized company in England called Red Gate. They call their products “ingeniously simple” and I must agree with that description. With SQL Packager you point to the database (more in a minute) you want to distribute. A few mouse clicks and dialogs and you have an executable file that you can ship virtually anywhere and virtually any way which, when run, installs the database on your destination SQL Server instance! It really is that simple. Easier to show than tell Let’s explore a hypothetical case. Let’s say you have a local SQL database of customers and you have decided you want to share it with your subsidiaries or partners. Here is the underlying screen you will see on starting SQL Packager. There are a bunch of possibilities here but I’m going to keep this relatively simple. At this point I simply want to illustrate the simplicity of generating an executable to deliver your database. You will notice that you can set up a new package, edit an existing package or change a bunch of options. Start SQL packager And the following is the default dialog you get on startup. In the next dialog, I’ve selected the Server and Database. I’ve also selected Windows Authentication. Pressing Next causes SQL Packager to run a number of checks and produce a report. Now you’re given a comprehensive list of what is going to be packaged and you’re allowed to change it if you desire. I’ve never made any changes here so I can’t really make any suggestions. The just illustrates the comprehensive nature of so many Red Gate products including this one. Clicking Next gives you still further options. SQL Packager then works its magic and shows you a dialog with the results. Packager then gives you a dialog of the scripts it has generated. The capture above only shows 1 of 4 tabs. Finally pressing Next gives you the option to generate a .NET executable of a C# project. I’ve only generated an executable so I’m not in a position to tell you what the C# project looks like. That may be the subject of further discussions. You can rename the package and tell SQL Packager where to save it. I’ve skipped a lot but this will serve to illustrate the comprehensive (and ingenious) things Red Gate does. All in all, it’s a superb way to distribute populated SQL databases. Oh – we’ll save running the resulting executable for later also but believe me it’s insanely simple.

  Read the article

• MSSQL: Copying data from one database to another

  - by DigiMortal

  I have database that has data imported from another server using import and export wizard of SQL Server Management Studio. There is also empty database with same tables but it also has primary keys, foreign keys and indexes. How to get data from first database to another? Here is the description of my crusade. And believe me – it is not nice one. Bugs in import and export wizard There is some awful bugs in import and export wizard that makes data imports and exports possible only on very limited manner: wizard is not able to analyze foreign keys, wizard wants to create tables always, whatever you say in settings. The result is faulty and useless package. Now let’s go step by step and make things work in our scenario. Database There are two databases. Let’s name them like this: PLAIN – contains data imported from remote server (no indexes, no keys, no nothing, just plain dumb data) CORRECT – empty database with same structure as remote database (indexes, keys and everything else but no data) Our goal is to get data from PLAIN to CORRECT. 1. Create import and export package In this point we will create faulty SSIS package using SQL Server Management Studio. Run import and export wizard and let it create SSIS package that reads data from CORRECT and writes it to, let’s say, CORRECT-2. Make sure you enable identity insert. Make sure there are no views selected. Make sure you don’t let package to create tables (you can miss this step because it wants to create tables anyway). Save package to SSIS. 2. Modify import and export package Now let’s clean up the package and remove all faulty crap. Connect SQL Server Management Studio to SSIS instance. Select the package you just saved and export it to your hard disc. Run Business Intelligence Studio. Create new SSIS project (DON’T MISS THIS STEP). Add package from disc as existing item to project and open it. Move to Control Flow page do one of following: Remove all preparation SQL-tasks and connect Data Flow tasks. Modify all preparation SQL-tasks so the existence of tables is checked before table is created (yes, you have to do it manually). Add new Execute-SQL task as first task in control flow: Open task properties. Assign destination connection as connection to use. Insert the following SQL as command:   EXEC sp_MSForEachTable 'ALTER TABLE ? NOCHECK CONSTRAINT ALL' GO   EXEC sp_MSForEachTable 'DELETE FROM ?' GO   Save task. Add new Execute-SQL task as last task in control flow: Open task properties. Assign destination connection as connection to use. Insert the following SQL as command:   EXEC sp_MSForEachTable 'ALTER TABLE ? CHECK CONSTRAINT ALL' GO   Save task Now connect first Execute-SQL task with first Data Flow task and last Data Flow task with second Execute-SQL task. Now move to Package Explorer tab and change connections under Connection Managers folder. Make source connection to use database PLAIN. Make destination connection to use database CORRECT. Save package and rebuilt the project. Update package using SQL Server Management Studio. Some hints: Make sure you take the package from solution folder because it is saved there now. Don’t overwrite existing package. Use numeric suffix and let Management Studio to create a new version of package. Now you are done with your package. Run it to test it and clean out all the errors you find. TRUNCATE vs DELETE You can see that I used DELETE FROM instead of TRUNCATE. Why? Because TRUNCATE has some nasty limits (taken from MSDN): “You cannot use TRUNCATE TABLE on a table referenced by a FOREIGN KEY constraint; instead, use DELETE statement without a WHERE clause. Because TRUNCATE TABLE is not logged, it cannot activate a trigger. TRUNCATE TABLE may not be used on tables participating in an indexed view.” As I am not sure what tables you have and how they are used I provided here the solution that should work for all scenarios. If you need better performance then in some cases you can use TRUNCATE table instead of DELETE. Conclusion My conclusion is bitter this time although I am very positive guy. It is A.D. 2010 and still we have to write stupid hacks for simple things. Simple tools that existed before are long gone and we have to live mysterious bloatware that is our only choice when using default tools. If you take a look at the length of this posting and the count of steps I had to do for one easy thing you should treat it as a signal that something has went wrong in last years. Although I got my job done I would be still more happy if out of box tools are more intelligent one day. References T-SQL Trick for Deleting All Data in Your Database (Mauro Cardarelli) TRUNCATE TABLE (MSDN Library) Error Handling in SQL 2000 – a Background (Erland Sommarskog) Disable/Enable Foreign Key and Check constraints in SQL Server (Decipher)

  Read the article

• How to Inspect Javascript Object

  - by Madhan ayyasamy

  You can inspect any JavaScript objects and list them as indented, ordered by levels.It shows you type and property name. If an object property can't be accessed, an error message will be shown.Here the snippets for inspect javascript object.function inspect(obj, maxLevels, level){  var str = '', type, msg;    // Start Input Validations    // Don't touch, we start iterating at level zero    if(level == null)  level = 0;    // At least you want to show the first level    if(maxLevels == null) maxLevels = 1;    if(maxLevels < 1)             return '<font color="red">Error: Levels number must be > 0</font>';    // We start with a non null object    if(obj == null)    return '<font color="red">Error: Object <b>NULL</b></font>';    // End Input Validations    // Each Iteration must be indented    str += '<ul>';    // Start iterations for all objects in obj    for(property in obj)    {      try      {          // Show "property" and "type property"          type =  typeof(obj[property]);          str += '<li>(' + type + ') ' + property +                  ( (obj[property]==null)?(': <b>null</b>'):('')) + '</li>';          // We keep iterating if this property is an Object, non null          // and we are inside the required number of levels          if((type == 'object') && (obj[property] != null) && (level+1 < maxLevels))          str += inspect(obj[property], maxLevels, level+1);      }      catch(err)      {        // Is there some properties in obj we can't access? Print it red.        if(typeof(err) == 'string') msg = err;        else if(err.message)        msg = err.message;        else if(err.description)    msg = err.description;        else                        msg = 'Unknown';        str += '<li><font color="red">(Error) ' + property + ': ' + msg +'</font></li>';      }    }      // Close indent      str += '</ul>';    return str;}Method Call:function inspect(obj [, maxLevels [, level]]) Input Vars * obj: Object to inspect * maxLevels: Optional. Number of levels you will inspect inside the object. Default MaxLevels=1 * level: RESERVED for internal use of the functionReturn ValueHTML formatted string containing all values of inspected object obj.

  Read the article

• How to export SQL Server data from corrupted database (with disk write error)

  - by damitamit

  IT realised there was a disk write error on our production SQL Server 2005 and hence was causing the backups to fail. By the time they had realised this the nightly backup was old, so were not able to just restore the backup on another server. The database is still running and being used constantly. However DBCC CheckDB fails. Also the SQL Server backup task fails, Copy Database fails, Export Data Wizard fails. However it seems all the data can be read from the tables (i.e using bcp etc) Another observation I have made is that the Transaction Log is nearly double the size of the Database. (Does that mean all the changes arent being written to the MDF?) What would be the best plan of attack to get the database to a state where backups are working and the data is safe? Take the database offline and use the MDF/LDF to somehow create the database on another sql server? Export the data from the database using bcp. Create the database (use the Generate Scripts function on the corrupt db to create the schema on the new db) on another sql server and use bcp again to import the data. Some other option that is the right course of action in this situation? The IT manager says the data is safe as if the server fails, the data can be restored from the mdf/ldf. I'm not sure so insisted that we start exporting the data each night as a failsafe (using bcp for example). IT are also having issues on the hardware side of things as supposedly the disk error in on a virtualized disk and can't be rebuilt like a normal raid array (or something like that). Please excuse my use of incorrect terminology and incorrect assumptions on how Sql Server operates. I'm the application developer and have been called to help (as it seems IT know less about SQL Server than I do). Many Thanks, Amit Results of DBBC CheckDB: Msg 1823, Level 16, State 2, Line 1 A database snapshot cannot be created because it failed to start. Msg 7928, Level 16, State 1, Line 1 The database snapshot for online checks could not be created. Either the reason is given in a previous error or one of the underlying volumes does not support sparse files or alternate streams. Attempting to get exclusive access to run checks offline. Msg 5030, Level 16, State 12, Line 1 The database could not be exclusively locked to perform the operation. Msg 7926, Level 16, State 1, Line 1 Check statement aborted. The database could not be checked as a database snapshot could not be created and the database or table could not be locked. See Books Online for details of when this behavior is expected and what workarounds exist. Also see previous errors for more details. Msg 823, Level 24, State 3, Line 1 The operating system returned error 1(error not found) to SQL Server during a write at offset 0x00000674706000 in file 'G:\AX40_Dynamics_Live.mdf'. Additional messages in the SQL Server error log and system event log may provide more detail. This is a severe system-level error condition that threatens database integrity and must be corrected immediately. Complete a full database consistency check (DBCC CHECKDB). This error can be caused by many factors; for more information, see SQL Server Books Online.

  Read the article

• Advantage Database Server: slow stored procedure performance.

  - by ie

  I have a question about a performance of stored procedures in the ADS. I created a simple database with the following structure: CREATE TABLE MainTable ( Id INTEGER PRIMARY KEY, Name VARCHAR(50), Value INTEGER ); CREATE UNIQUE INDEX MainTableName_UIX ON MainTable ( Name ); CREATE TABLE SubTable ( Id INTEGER PRIMARY KEY, MainId INTEGER, Name VARCHAR(50), Value INTEGER ); CREATE INDEX SubTableMainId_UIX ON SubTable ( MainId ); CREATE UNIQUE INDEX SubTableName_UIX ON SubTable ( Name ); CREATE PROCEDURE CreateItems ( MainName VARCHAR ( 20 ), SubName VARCHAR ( 20 ), MainValue INTEGER, SubValue INTEGER, MainId INTEGER OUTPUT, SubId INTEGER OUTPUT ) BEGIN DECLARE @MainName VARCHAR ( 20 ); DECLARE @SubName VARCHAR ( 20 ); DECLARE @MainValue INTEGER; DECLARE @SubValue INTEGER; DECLARE @MainId INTEGER; DECLARE @SubId INTEGER; @MainName = (SELECT MainName FROM __input); @SubName = (SELECT SubName FROM __input); @MainValue = (SELECT MainValue FROM __input); @SubValue = (SELECT SubValue FROM __input); @MainId = (SELECT MAX(Id)+1 FROM MainTable); @SubId = (SELECT MAX(Id)+1 FROM SubTable ); INSERT INTO MainTable (Id, Name, Value) VALUES (@MainId, @MainName, @MainValue); INSERT INTO SubTable (Id, Name, MainId, Value) VALUES (@SubId, @SubName, @MainId, @SubValue); INSERT INTO __output SELECT @MainId, @SubId FROM system.iota; END; CREATE PROCEDURE UpdateItems ( MainName VARCHAR ( 20 ), MainValue INTEGER, SubValue INTEGER ) BEGIN DECLARE @MainName VARCHAR ( 20 ); DECLARE @MainValue INTEGER; DECLARE @SubValue INTEGER; DECLARE @MainId INTEGER; @MainName = (SELECT MainName FROM __input); @MainValue = (SELECT MainValue FROM __input); @SubValue = (SELECT SubValue FROM __input); @MainId = (SELECT TOP 1 Id FROM MainTable WHERE Name = @MainName); UPDATE MainTable SET Value = @MainValue WHERE Id = @MainId; UPDATE SubTable SET Value = @SubValue WHERE MainId = @MainId; END; CREATE PROCEDURE SelectItems ( MainName VARCHAR ( 20 ), CalculatedValue INTEGER OUTPUT ) BEGIN DECLARE @MainName VARCHAR ( 20 ); @MainName = (SELECT MainName FROM __input); INSERT INTO __output SELECT m.Value * s.Value FROM MainTable m INNER JOIN SubTable s ON m.Id = s.MainId WHERE m.Name = @MainName; END; CREATE PROCEDURE DeleteItems ( MainName VARCHAR ( 20 ) ) BEGIN DECLARE @MainName VARCHAR ( 20 ); DECLARE @MainId INTEGER; @MainName = (SELECT MainName FROM __input); @MainId = (SELECT TOP 1 Id FROM MainTable WHERE Name = @MainName); DELETE FROM SubTable WHERE MainId = @MainId; DELETE FROM MainTable WHERE Id = @MainId; END; Actually, the problem I had - even so light stored procedures work very-very slow (about 50-150 ms) relatively to plain queries (0-5ms). To test the performance, I created a simple test (in F# using ADS ADO.NET provider): open System; open System.Data; open System.Diagnostics; open Advantage.Data.Provider; let mainName = "main name #"; let subName = "sub name #"; // INSERT let cmdTextScriptInsert = " DECLARE @MainId INTEGER; DECLARE @SubId INTEGER; @MainId = (SELECT MAX(Id)+1 FROM MainTable); @SubId = (SELECT MAX(Id)+1 FROM SubTable ); INSERT INTO MainTable (Id, Name, Value) VALUES (@MainId, :MainName, :MainValue); INSERT INTO SubTable (Id, Name, MainId, Value) VALUES (@SubId, :SubName, @MainId, :SubValue); SELECT @MainId, @SubId FROM system.iota;"; let cmdTextProcedureInsert = "CreateItems"; // UPDATE let cmdTextScriptUpdate = " DECLARE @MainId INTEGER; @MainId = (SELECT TOP 1 Id FROM MainTable WHERE Name = :MainName); UPDATE MainTable SET Value = :MainValue WHERE Id = @MainId; UPDATE SubTable SET Value = :SubValue WHERE MainId = @MainId;"; let cmdTextProcedureUpdate = "UpdateItems"; // SELECT let cmdTextScriptSelect = " SELECT m.Value * s.Value FROM MainTable m INNER JOIN SubTable s ON m.Id = s.MainId WHERE m.Name = :MainName;"; let cmdTextProcedureSelect = "SelectItems"; // DELETE let cmdTextScriptDelete = " DECLARE @MainId INTEGER; @MainId = (SELECT TOP 1 Id FROM MainTable WHERE Name = :MainName); DELETE FROM SubTable WHERE MainId = @MainId; DELETE FROM MainTable WHERE Id = @MainId;"; let cmdTextProcedureDelete = "DeleteItems"; let cnnStr = @"data source=D:\DB\test.add; ServerType=local; user id=adssys; password=***;"; let cnn = new AdsConnection(cnnStr); try cnn.Open(); let cmd = cnn.CreateCommand(); let parametrize ix prms = cmd.Parameters.Clear(); let addParam = function | "MainName" -> cmd.Parameters.Add(":MainName" , mainName + ix.ToString()) |> ignore; | "SubName" -> cmd.Parameters.Add(":SubName" , subName + ix.ToString() ) |> ignore; | "MainValue" -> cmd.Parameters.Add(":MainValue", ix * 3 ) |> ignore; | "SubValue" -> cmd.Parameters.Add(":SubValue" , ix * 7 ) |> ignore; | _ -> () prms |> List.iter addParam; let runTest testData = let (cmdType, cmdName, cmdText, cmdParams) = testData; let toPrefix cmdType cmdName = let prefix = match cmdType with | CommandType.StoredProcedure -> "Procedure-" | CommandType.Text -> "Script -" | _ -> "Unknown -" in prefix + cmdName; let stopWatch = new Stopwatch(); let runStep ix prms = parametrize ix prms; stopWatch.Start(); cmd.ExecuteNonQuery() |> ignore; stopWatch.Stop(); cmd.CommandText <- cmdText; cmd.CommandType <- cmdType; let startId = 1500; let count = 10; for id in startId .. startId+count do runStep id cmdParams; let elapsed = stopWatch.Elapsed; Console.WriteLine("Test '{0}' - total: {1}; per call: {2}ms", toPrefix cmdType cmdName, elapsed, Convert.ToInt32(elapsed.TotalMilliseconds)/count); let lst = [ (CommandType.Text, "Insert", cmdTextScriptInsert, ["MainName"; "SubName"; "MainValue"; "SubValue"]); (CommandType.Text, "Update", cmdTextScriptUpdate, ["MainName"; "MainValue"; "SubValue"]); (CommandType.Text, "Select", cmdTextScriptSelect, ["MainName"]); (CommandType.Text, "Delete", cmdTextScriptDelete, ["MainName"]) (CommandType.StoredProcedure, "Insert", cmdTextProcedureInsert, ["MainName"; "SubName"; "MainValue"; "SubValue"]); (CommandType.StoredProcedure, "Update", cmdTextProcedureUpdate, ["MainName"; "MainValue"; "SubValue"]); (CommandType.StoredProcedure, "Select", cmdTextProcedureSelect, ["MainName"]); (CommandType.StoredProcedure, "Delete", cmdTextProcedureDelete, ["MainName"])]; lst |> List.iter runTest; finally cnn.Close(); And I'm getting the following results: Test 'Script -Insert' - total: 00:00:00.0292841; per call: 2ms Test 'Script -Update' - total: 00:00:00.0056296; per call: 0ms Test 'Script -Select' - total: 00:00:00.0051738; per call: 0ms Test 'Script -Delete' - total: 00:00:00.0059258; per call: 0ms Test 'Procedure-Insert' - total: 00:00:01.2567146; per call: 125ms Test 'Procedure-Update' - total: 00:00:00.7442440; per call: 74ms Test 'Procedure-Select' - total: 00:00:00.5120446; per call: 51ms Test 'Procedure-Delete' - total: 00:00:01.0619165; per call: 106ms The situation with the remote server is much better, but still a great gap between plaqin queries and stored procedures: Test 'Script -Insert' - total: 00:00:00.0709299; per call: 7ms Test 'Script -Update' - total: 00:00:00.0161777; per call: 1ms Test 'Script -Select' - total: 00:00:00.0258113; per call: 2ms Test 'Script -Delete' - total: 00:00:00.0166242; per call: 1ms Test 'Procedure-Insert' - total: 00:00:00.5116138; per call: 51ms Test 'Procedure-Update' - total: 00:00:00.3802251; per call: 38ms Test 'Procedure-Select' - total: 00:00:00.1241245; per call: 12ms Test 'Procedure-Delete' - total: 00:00:00.4336334; per call: 43ms Is it any chance to improve the SP performance? Please advice. ADO.NET driver version - 9.10.2.9 Server version - 9.10.0.9 (ANSI - GERMAN, OEM - GERMAN) Thanks!

  Read the article

• archiving strategies and limitations of data in a table

  - by Samuel

  Environment: Jboss, Mysql, JPA, Hibernate Our web application will be catering to a large amount of users (~ 1,000,000) and there are a lots of child table where user specific data are stored (e.g. personal, health, forum contributions ...). What would be the best practice to archive user & user specific information. [a] Would it be wise to move the archived user & user specific information to their respective tables within the same database (e.g. user_archive, user_forum_comments_archive ...) OR [b] Would you just mark the database entries with a flag in the original table(s) and just query only non archived entries. We have a unique constraint on User.loginid, how do you handle this requirement if the users are archived via 1-[a] (i.e if a user with loginid 'samuel' gets moved into the archive table and if a new user gets added with the same name in the original table, how would you prevent this. What would be the best strategy to address the unique key constraints. We have a requirement to selectively archive records and bring it back if necessary, will you rely on database tools are would you handle this via your persistence APIs exposed by the JPA entity model.

  Read the article

• Are bad data issues that common?

  - by Water Cooler v2

  I've worked for clients that had a large number of distinct, small to mid-sized projects, each interacting with each other via properly defined interfaces to share data, but not reading and writing to the same database. Each had their own separate database, their own cache, their own file servers/system that they had dedicated access to, and so they never caused any problems. One of these clients is a mobile content vendor, so they're lucky in a way that they do not have to face the same problems that everyday business applications do. They can create all those separate compartments where their components happily live in isolation of the others. However, for many business applications, this is not possible. I've worked with a few clients, one of whose applications I am doing the production support for, where there are "bad data issues" on an hourly basis. Yeah, it's that crazy. Some data records from one of the instances (lower than production, of course) would have been run a couple of weeks ago, and caused some other user's data to get corrupted. And then, a data script will have to be written to fix this issue. And I've seen this happening so much with this client that I have to ask. I've seen this happening at a moderate rate with other clients, but this one just seems to be out of order. If you're working with business applications that share a large amount of data by reading and writing to/from the same database, are "bad data issues" that common in your environment?

  Read the article

• How To - Guide to Importing Data from a MySQL Database to Excel using MySQL for Excel

  - by Javier Treviño

  Fetching data from a database to then get it into an Excel spreadsheet to do analysis, reporting, transforming, sharing, etc. is a very common task among users. There are several ways to extract data from a MySQL database to then import it to Excel; for example you can use the MySQL Connector/ODBC to configure an ODBC connection to a MySQL database, then in Excel use the Data Connection Wizard to select the database and table from which you want to extract data from, then specify what worksheet you want to put the data into.  Another way is to somehow dump a comma delimited text file with the data from a MySQL table (using the MySQL Command Line Client, MySQL Workbench, etc.) to then in Excel open the file using the Text Import Wizard to attempt to correctly split the data in columns. These methods are fine, but involve some degree of technical knowledge to make the magic happen and involve repeating several steps each time data needs to be imported from a MySQL table to an Excel spreadsheet. So, can this be done in an easier and faster way? With MySQL for Excel you can. MySQL for Excel features an Import MySQL Data action where you can import data from a MySQL Table, View or Stored Procedure literally with a few clicks within Excel.  Following is a quick guide describing how to import data using MySQL for Excel. This guide assumes you already have a working MySQL Server instance, Microsoft Office Excel 2007 or 2010 and MySQL for Excel installed. 1. Opening MySQL for Excel Being an Excel Add-In, MySQL for Excel is opened from within Excel, so to use it open Excel, go to the Data tab located in the Ribbon and click MySQL for Excel at the far right of the Ribbon. 2. Creating a MySQL Connection (may be optional) If you have MySQL Workbench installed you will automatically see the same connections that you can see in MySQL Workbench, so you can use any of those and there may be no need to create a new connection. If you want to create a new connection (which normally you will do only once), in the Welcome Panel click New Connection, which opens the Setup New Connection dialog. Here you only need to give your new connection a distinctive Connection Name, specify the Hostname (or IP address) where the MySQL Server instance is running on (if different than localhost), the Port to connect to and the Username for the login. If you wish to test if your setup is good to go, click Test Connection and an information dialog will pop-up stating if the connection is successful or errors were found. 3.Opening a connection to a MySQL Server To open a pre-configured connection to a MySQL Server you just need to double-click it, so the Connection Password dialog is displayed where you enter the password for the login. 4. Selecting a MySQL Schema After opening a connection to a MySQL Server, the Schema Selection Panel is shown, where you can select the Schema that contains the Tables, Views and Stored Procedures you want to work with. To do so, you just need to either double-click the desired Schema or select it and click Next >. 5. Importing data… All previous steps were really the basic minimum needed to drill-down to the DB Object Selection Panel  where you can see the Database Objects (grouped by type: Tables, Views and Procedures in that order) that you want to perform actions against; in the case of this guide, the action of importing data from them. a. From a MySQL Table To import from a Table you just need to select it from the list of Database Objects’ Tables group, after selecting it you will note actions below the list become available; then click Import MySQL Data. The Import Data dialog is displayed; you can see some basic information here like the name of the Excel worksheet the data will be imported to (in the window title), the Table Name, the total Row Count and a 10 row preview of the data meant for the user to see the columns that the table contains and to provide a way to select which columns to import. The Import Data dialog is designed with defaults in place so all data is imported (all rows and all columns) by just clicking Import; this is important to minimize the number of clicks needed to get the job done. After the import is performed you will have the data in the Excel worksheet formatted automatically. If you need to override the defaults in the Import Data dialog to change the columns selected for import or to change the number of imported rows you can easily do so before clicking Import. In the screenshot below the defaults are overridden to import only the first 3 columns and rows 10 – 60 (Limit to 50 Rows and Start with Row 10). If the number of rows to be imported exceeds the maximum number of rows Excel can hold in its worksheet, a warning will be displayed in the dialog, meaning the imported number of rows will be limited by that maximum number (65,535 rows if the worksheet is in Compatibility Mode).  In the screenshot below you can see the Table contains 80,559 rows, but only 65,534 rows will be imported since the first row is used for the column names if the Include Column Names as Headers checkbox is checked. b. From a MySQL View Similar to the way of importing from a Table, to import from a View you just need to select it from the list of Database Objects’ Views group, then click Import MySQL Data. The Import Data dialog is displayed; identically to the way everything looks when importing from a table, the dialog displays the View Name, the total Row Count and the data preview grid. Since Views are really a filtered way to display data from Tables, it is actually as if we are extracting data from a Table; so the Import Data dialog is actually identical for those 2 Database Objects. After the import is performed, the data in the Excel spreadsheet looks like the following screenshot. Note that you can override the defaults in the Import Data dialog in the same way described above for importing data from Tables. Also the Compatibility Mode warning will be displayed if data exceeds the maximum number of rows explained before. c. From a MySQL Procedure Too import from a Procedure you just need to select it from the list of Database Objects’ Procedures group (note you can see Procedures here but not Functions since these return a single value, so by design they are filtered out). After the selection is made, click Import MySQL Data. The Import Data dialog is displayed, but this time you can see it looks different to the one used for Tables and Views.  Given the nature of Store Procedures, they require first that values are supplied for its Parameters and also Procedures can return multiple Result Sets; so the Import Data dialog shows the Procedure Name and the Procedure Parameters in a grid where their values are input. After you supply the Parameter Values click Call. After calling the Procedure, the Result Sets returned by it are displayed at the bottom of the dialog; output parameters and the return value of the Procedure are appended as the last Result Set of the group. You can see each Result Set is displayed as a tab so you can see a preview of the returned data.  You can specify if you want to import the Selected Result Set (default), All Result Sets – Arranged Horizontally or All Result Sets – Arranged Vertically using the Import drop-down list; then click Import. After the import is performed, the data in the Excel spreadsheet looks like the following screenshot.  Note in this example all Result Sets were imported and arranged vertically. As you can see using MySQL for Excel importing data from a MySQL database becomes an easy task that requires very little technical knowledge, so it can be done by any type of user. Hope you enjoyed this guide! Remember that your feedback is very important for us, so drop us a message: MySQL on Windows (this) Blog - https://blogs.oracle.com/MySqlOnWindows/ Forum - http://forums.mysql.com/list.php?172 Facebook - http://www.facebook.com/mysql Cheers!

  Read the article

• FOUR questions to ask if you are implementing DATABASE-AS-A-SERVICE

  - by Sudip Datta

  During my ongoing tenure at Oracle, I have met all types of DBAs. Happy DBAs, unhappy DBAs, proud DBAs, risk-loving DBAs, cautious DBAs. These days, as Database-as-a-Service (DBaaS) becomes more mainstream, I find some complacent DBAs who are basking in their achievement of having implemented DBaaS. Some others, however, are not that happy. They grudgingly complain that they did not have much of a say in the implementation, they simply had to follow what their cloud architects (mostly infrastructure admins) offered them. In most cases it would be a database wrapped inside a VM that would be labeled as “Database as a Service”. In other cases, it would be existing brute-force automation simply exposed in a portal. As much as I think that there is more to DBaaS than those approaches and often get tempted to propose Enterprise Manager 12c, I try to be objective. Neither do I want to dampen the spirit of the happy ones, nor do I want to stoke the pain of the unhappy ones. As I mentioned in my previous post, I don’t deny vanilla automation could be useful. I like virtualization too for what it has helped us accomplish in terms of resource management, but we need to scrutinize its merit on a case-by-case basis and apply it meaningfully. For DBAs who either claim to have implemented DBaaS or are planning to do so, I simply want to provide four key questions to ponder about: 1. Does it make life easier for your end users? Database-as-a-Service can have several types of end users. Junior DBAs, QA Engineers, Developers- each having their own skillset. The objective of DBaaS is to make their life simple, so that they can focus on their core responsibilities without having to worry about additional stuff. For example, if you are a Developer using Oracle Application Express (APEX), you want to deal with schema, objects and PL/SQL code and not with datafiles or listener configuration. If you are a QA Engineer needing database copies for functional testing, you do not want to deal with underlying operating system patching and compliance issues. The question to ask, therefore, is, whether DBaaS makes life easier for those users. It is often convenient to give them VM shells to deal with a la Amazon EC2 IaaS, but is that what they really want? Is it a productive use of a developer's time if he needs to apply RPM errata to his Linux operating system. Asking him to keep the underlying operating system current is like making a guest responsible for a restaurant's decor. 2. Does it make life easier for your administrators? Cloud, in general, is supposed to free administrators from attending to mundane tasks like provisioning services for every single end user request. It is supposed to enable a readily consumable platform and enforce standardization in the process. For example, if a Service Catalog exposes DBaaS of specific database versions and configurations, it, by its very nature, enforces certain discipline and standardization within the IT environment. What if, instead of specific database configurations, cloud allowed each end user to create databases of their liking resulting in hundreds of version and patch levels and thousands of individual databases. Therefore the right question to ask is whether the unwanted consequence of DBaaS is OS and database sprawl. And if so, who is responsible for tracking them, backing them up, administering them? Studies have shown that these administrative overheads increase exponentially with new targets, and it could result in a management nightmare. That leads us to our next question. 3. Does it satisfy your Security Officers and Compliance Auditors? Compliance Auditors need to know who did what and when. They also want the cloud platform to be secure, so that end users have little freedom in tampering with it. Dealing with VM sprawl is not the easiest of challenges, let alone dealing with them as they keep getting reconfigured and moved around. This leads to the proverbial needle in the haystack problem, and all it needs is one needle to cause a serious compliance issue in the enterprise. Bottomline is, flexibility and agility should not come at the expense of compliance and it is very important to get the balance right. Can we have security and isolation without creating compliance challenges? Instead of a ‘one size fits all approach’ i.e. OS level isolation, can we think smartly about database isolation or schema based isolation? This is where the appropriate resource modeling needs to be applied. The usual systems management vendors out there with heterogeneous common-denominator approach have compromised on these semantics. If you follow Enterprise Manager’s DBaaS solution, you will see that we have considered different models, not precluding virtualization, for different customer use cases. The judgment to use virtual assemblies versus databases on physical RAC versus Schema-as-a-Service in a single database, should be governed by the need of the applications and not by putting compliance considerations in the backburner. 4. Does it satisfy your CIO? Finally, does it satisfy your higher ups? As the sponsor of cloud initiative, the CIO is expected to lead an IT transformation project, not merely a run-of-the-mill IT operations. Simply virtualizing server resources and delivering them through self-service is a good start, but hardly transformational. CIOs may appreciate the instant benefit from server consolidation, but studies have revealed that the ROI from consolidation would flatten out at 20-25%. The question would be: what next? As we go higher up in the stack, the need to virtualize, segregate and optimize shifts to those layers that are more palpable to the business users. As Sushil Kumar noted in his blog post, " the most important thing to note here is the enterprise private cloud is not just an IT project, rather it is a business initiative to create an IT setup that is more aligned with the needs of today's dynamic and highly competitive business environment." Business users could not care less about infrastructure consolidation or virtualization - they care about business agility and service level assurance. Last but not the least, lot of CIOs get miffed if we ask them to throw away their existing hardware investments for implementing DBaaS. In Oracle, we always emphasize on freedom of choosing a platform; hence Enterprise Manager’s DBaaS solution is platform neutral. It can work on any Operating System (that the agent is certified on) Oracle’s hardware as well as 3rd party hardware. As a parting note, I urge you to remember these 4 questions. Remember that your satisfaction as an implementer lies in the satisfaction of others.

  Read the article

• Best way to test if an object is in a set of objects?

  - by jdelator

  I'm trying to avoid using a long else if statement. Lets say I have an object and I want to test if it's of type ClassA, ClassB, ClassC, etc..? What is a clean way of doing this?

  Read the article

• Recommend an Appropriate Object-Orientated Design Pattern To Replace This Code....

  - by Rob P.

  I have a menu click event that looks something like this.... Public Sub ToolbarManager_ToolClick(sender as Object, e as EventArgs) Case "New" CreateNewFile() Case "Save" SaveCurrentFile() Case "Exit" ExitApp() Case....... etc... etc... End Sub This strikes me as being 'ugly' - but I'm unsure of the 'best' way or the most appropriate way to clean it up.

  Read the article

• Could a derived-class object treated as if it's the same type of a bases class? <noobieQ/>

  - by M4design

  Say I got: class X_ { public: void do() { } } class Y_ : public X_ { } And I have this function: void foo(X_ whatever) { whatever.do(); } Can I send a "Y_" object to the foo function, would this work? I just realized that I could have tested this myself :)

  Read the article

• Export and import a PostgreSQL database with a different name?

  - by J. Pablo Fernández

  Is there a way to export a PostgreSQL database and later import it with another name? I'm using PostgreSQL with Rails and I often export the data from production, where the database is called blah_production and import it on development or staging with names blah_development and blah_staging. On MySQL this is trivial as the export doesn't have the database anywhere (except a comment maybe), but on PostgreSQL it seems to be impossible. Is it impossible? I've seen out there some people using sed scripts to modify the dump. I'd like to avoid that solution but if there are no alternative I'll take it. Has anybody wrote a script to alter the dump's database name ensure no data is ever altered?

  Read the article

• What are the pros of switching DNS names with a database server hardware upgrade?

  - by wilbbe01

  When we upgrade to new hardware at work we usually increment a number in the DNS name. For example. We have a server called database-2, that is slated to become database-3 in the coming days. I haven't been able to find a good reason why this is good behavior. To me the work of trying to catch all end user machines, as well as all servers dependent on the database server is far riskier than simply moving the database and ip/name with it to the new hardware. A little over a year ago we spent several months of requests coming in, as infrequent users began using software that needed to be updated to point to a new DNS name. I am struggling to find answers as to why this is a good practice. So the question. Why is using DNS names as a "server hardware version identifier" a good idea? What am I overlooking? Thanks much.

  Read the article

• Gathering statistics for an Oracle WebCenter Content Database

  - by Nicolas Montoya

  Have you ever heard: "My Oracle WebCenter Content instance is running slow. I checked the memory and CPU usage of the application server and it has plenty of resources. What could be going wrong?An Oracle WebCenter Content instance runs on an application server and relies on a database server on the back end. If your application server tier is running fine, chances are that your database server tier may host the root of the problem. While many things could cause performance problems, on active Enterprise Content Management systems, keeping database statistics updated is extremely important.The Oracle Database have a set of built-in optimizer utilities that can help make database queries more efficient. It is strongly recommended to update or re-create the statistics about the physical characteristics of a table and the associated indexes in order to maximize the efficiency of optimizers. These physical characteristics include: Number of records Number of pages Average record length The frequency with which you need to update statistics depends on how quickly the data is changing. Typically, statistics should be updated when the number of new items since the last update is greater than ten percent of the number of items when the statistics were last updated. If a large amount of documents are being added or removed from the system, the a post step should be added to gather statistics upon completion of this massive data change. In some cases, you may need to collect statistics in the middle of the data processing to expedite its execution. These proceses include but are not limited to: data migration, bootstrapping of a new system, records management disposition processing (typically at the end of the calendar year), etc. A DOCUMENTS table with a ten million rows will often generate a very different plan than a table with just a thousand.A quick check of the statistics for the WebCenter Content (WCC) Database could be performed via the below query:SELECT OWNER, TABLE_NAME, NUM_ROWS, BLOCKS, AVG_ROW_LEN,TO_CHAR(LAST_ANALYZED, 'MM/DD/YYYY HH24:MI:SS')FROM DBA_TABLESWHERE TABLE_NAME='DOCUMENTS';OWNER                          TABLE_NAME                       NUM_ROWS------------------------------ ------------------------------ ----------    BLOCKS AVG_ROW_LEN TO_CHAR(LAST_ANALYZ---------- ----------- -------------------ATEAM_OCS                      DOCUMENTS                            4172        46          61 04/06/2012 11:17:51This output will return not only the date when the WCC table DOCUMENTS was last analyzed, but also it will return the <DATABASE SCHEMA OWNER> for this table in the form of <PREFIX>_OCS.This database username could later on be used to check on other objects owned by the WCC <DATABASE SCHEMA OWNER> as shown below:SELECT OWNER, TABLE_NAME, NUM_ROWS, BLOCKS, AVG_ROW_LEN,TO_CHAR(LAST_ANALYZED, 'MM/DD/YYYY HH24:MI:SS')FROM DBA_TABLESWHERE OWNER='ATEAM_OCS'ORDER BY NUM_ROWS ASC;...OWNER                          TABLE_NAME                       NUM_ROWS------------------------------ ------------------------------ ----------    BLOCKS AVG_ROW_LEN TO_CHAR(LAST_ANALYZ---------- ----------- -------------------ATEAM_OCS                      REVISIONS                            2051        46         141 04/09/2012 22:00:22ATEAM_OCS                      DOCUMENTS                            4172        46          61 04/06/2012 11:17:51ATEAM_OCS                      ARCHIVEHISTORY                       4908       244         218 04/06/2012 11:17:49OWNER                          TABLE_NAME                       NUM_ROWS------------------------------ ------------------------------ ----------    BLOCKS AVG_ROW_LEN TO_CHAR(LAST_ANALYZ---------- ----------- -------------------ATEAM_OCS                      DOCUMENTHISTORY                      5865       110          72 04/06/2012 11:17:50ATEAM_OCS                      SCHEDULEDJOBSHISTORY                10131       244         131 04/06/2012 11:17:54ATEAM_OCS                      SCTACCESSLOG                        10204       496         268 04/06/2012 11:17:54...The Oracle Database allows to collect statistics of many different kinds as an aid to improving performance. The DBMS_STATS package is concerned with optimizer statistics only. The database sets automatic statistics collection of this kind on by default, DBMS_STATS package is intended for only specialized cases.The following subprograms gather certain classes of optimizer statistics:GATHER_DATABASE_STATS Procedures GATHER_DICTIONARY_STATS Procedure GATHER_FIXED_OBJECTS_STATS Procedure GATHER_INDEX_STATS Procedure GATHER_SCHEMA_STATS Procedures GATHER_SYSTEM_STATS Procedure GATHER_TABLE_STATS ProcedureThe DBMS_STATS.GATHER_SCHEMA_STATS PL/SQL Procedure gathers statistics for all objects in a schema.DBMS_STATS.GATHER_SCHEMA_STATS (    ownname          VARCHAR2,    estimate_percent NUMBER   DEFAULT to_estimate_percent_type                                                 (get_param('ESTIMATE_PERCENT')),    block_sample     BOOLEAN  DEFAULT FALSE,    method_opt       VARCHAR2 DEFAULT get_param('METHOD_OPT'),   degree           NUMBER   DEFAULT to_degree_type(get_param('DEGREE')),    granularity      VARCHAR2 DEFAULT GET_PARAM('GRANULARITY'),    cascade          BOOLEAN  DEFAULT to_cascade_type(get_param('CASCADE')),    stattab          VARCHAR2 DEFAULT NULL,    statid           VARCHAR2 DEFAULT NULL,    options          VARCHAR2 DEFAULT 'GATHER',    objlist          OUT      ObjectTab,   statown          VARCHAR2 DEFAULT NULL,    no_invalidate    BOOLEAN  DEFAULT to_no_invalidate_type (                                     get_param('NO_INVALIDATE')),  force             BOOLEAN DEFAULT FALSE);There are several values for the OPTIONS parameter that we need to know about: GATHER reanalyzes the whole schema     GATHER EMPTY only analyzes tables that have no existing statistics GATHER STALE only reanalyzes tables with more than 10 percent modifications (inserts, updates,   deletes) GATHER AUTO will reanalyze objects that currently have no statistics and objects with stale statistics. Using GATHER AUTO is like combining GATHER STALE and GATHER EMPTY. Example:exec dbms_stats.gather_schema_stats( -   ownname          => '<PREFIX>_OCS', -   options          => 'GATHER AUTO' -);

  Read the article

• Database Migration Scripts: Getting from place A to place B

  - by Phil Factor

  We’ll be looking at a typical database ‘migration’ script which uses an unusual technique to migrate existing ‘de-normalised’ data into a more correct form. So, the book-distribution business that uses the PUBS database has gradually grown organically, and has slipped into ‘de-normalisation’ habits. What’s this? A new column with a list of tags or ‘types’ assigned to books. Because books aren’t really in just one category, someone has ‘cured’ the mismatch between the database and the business requirements. This is fine, but it is now proving difficult for their new website that allows searches by tags. Any request for history book really has to look in the entire list of associated tags rather than the ‘Type’ field that only keeps the primary tag. We have other problems. The TypleList column has duplicates in there which will be affecting the reporting, and there is the danger of mis-spellings getting there. The reporting system can’t be persuaded to do reports based on the tags and the Database developers are complaining about the unCoddly things going on in their database. In your version of PUBS, this extra column doesn’t exist, so we’ve added it and put in 10,000 titles using SQL Data Generator. /* So how do we refactor this database? firstly, we create a table of all the tags. */IF  OBJECT_ID('TagName') IS NULL OR OBJECT_ID('TagTitle') IS NULL  BEGIN  CREATE TABLE  TagName (TagName_ID INT IDENTITY(1,1) PRIMARY KEY ,     Tag VARCHAR(20) NOT NULL UNIQUE)  /* ...and we insert into it all the tags from the list (remembering to take out any leading spaces */  INSERT INTO TagName (Tag)     SELECT DISTINCT LTRIM(x.y.value('.', 'Varchar(80)')) AS [Tag]     FROM     (SELECT  Title_ID,          CONVERT(XML, '<list><i>' + REPLACE(TypeList, ',', '</i><i>') + '</i></list>')          AS XMLkeywords          FROM   dbo.titles)g    CROSS APPLY XMLkeywords.nodes('/list/i/text()') AS x ( y )  /* we can then use this table to provide a table that relates tags to articles */  CREATE TABLE TagTitle   (TagTitle_ID INT IDENTITY(1, 1),   [title_id] [dbo].[tid] NOT NULL REFERENCES titles (Title_ID),   TagName_ID INT NOT NULL REFERENCES TagName (Tagname_ID)   CONSTRAINT [PK_TagTitle]       PRIMARY KEY CLUSTERED ([title_id] ASC, TagName_ID)       ON [PRIMARY])        CREATE NONCLUSTERED INDEX idxTagName_ID  ON  TagTitle (TagName_ID)  INCLUDE (TagTitle_ID,title_id)        /* ...and it is easy to fill this with the tags for each title ... */        INSERT INTO TagTitle (Title_ID, TagName_ID)    SELECT DISTINCT Title_ID, TagName_ID      FROM        (SELECT  Title_ID,          CONVERT(XML, '<list><i>' + REPLACE(TypeList, ',', '</i><i>') + '</i></list>')          AS XMLkeywords          FROM   dbo.titles)g    CROSS APPLY XMLkeywords.nodes('/list/i/text()') AS x ( y )    INNER JOIN TagName ON TagName.Tag=LTRIM(x.y.value('.', 'Varchar(80)'))    END    /* That's all there was to it. Now we can select all titles that have the military tag, just to try things out */SELECT Title FROM titles  INNER JOIN TagTitle ON titles.title_ID=TagTitle.Title_ID  INNER JOIN Tagname ON Tagname.TagName_ID=TagTitle.TagName_ID  WHERE tagname.tag='Military'/* and see the top ten most popular tags for titles */SELECT Tag, COUNT(*) FROM titles  INNER JOIN TagTitle ON titles.title_ID=TagTitle.Title_ID  INNER JOIN Tagname ON Tagname.TagName_ID=TagTitle.TagName_ID  GROUP BY Tag ORDER BY COUNT(*) DESC/* and if you still want your list of tags for each title, then here they are */SELECT title_ID, title, STUFF(  (SELECT ','+tagname.tag FROM titles thisTitle    INNER JOIN TagTitle ON titles.title_ID=TagTitle.Title_ID    INNER JOIN Tagname ON Tagname.TagName_ID=TagTitle.TagName_ID  WHERE ThisTitle.title_id=titles.title_ID  FOR XML PATH(''), TYPE).value('.', 'varchar(max)')  ,1,1,'')    FROM titles  ORDER BY title_ID So we’ve refactored our PUBS database without pain. We’ve even put in a check to prevent it being re-run once the new tables are created. Here is the diagram of the new tag relationship We’ve done both the DDL to create the tables and their associated components, and the DML to put the data in them. I could have also included the script to remove the de-normalised TypeList column, but I’d do a whole lot of tests first before doing that. Yes, I’ve left out the assertion tests too, which should check the edge cases and make sure the result is what you’d expect. One thing I can’t quite figure out is how to deal with an ordered list using this simple XML-based technique. We can ensure that, if we have to produce a list of tags, we can get the primary ‘type’ to be first in the list, but what if the entire order is significant? Thank goodness it isn’t in this case. If it were, we might have to revisit a string-splitter function that returns the ordinal position of each component in the sequence. You’ll see immediately that we can create a synchronisation script for deployment from a comparison tool such as SQL Compare, to change the schema (DDL). On the other hand, no tool could do the DML to stuff the data into the new table, since there is no way that any tool will be able to work out where the data should go. We used some pretty hairy code to deal with a slightly untypical problem. We would have to do this migration by hand, and it has to go into source control as a batch. If most of your database changes are to be deployed by an automated process, then there must be a way of over-riding this part of the data synchronisation process to do this part of the process taking the part of the script that fills the tables, Checking that the tables have not already been filled, and executing it as part of the transaction. Of course, you might prefer the approach I’ve taken with the script of creating the tables in the same batch as the data conversion process, and then using the presence of the tables to prevent the script from being re-run. The problem with scripting a refactoring change to a database is that it has to work both ways. If we install the new system and then have to rollback the changes, several books may have been added, or had their tags changed, in the meantime. Yes, you have to script any rollback! These have to be mercilessly tested, and put in source control just in case of the rollback of a deployment after it has been in place for any length of time. I’ve shown you how to do this with the part of the script .. /* and if you still want your list of tags for each title, then here they are */SELECT title_ID, title, STUFF(  (SELECT ','+tagname.tag FROM titles thisTitle    INNER JOIN TagTitle ON titles.title_ID=TagTitle.Title_ID    INNER JOIN Tagname ON Tagname.TagName_ID=TagTitle.TagName_ID  WHERE ThisTitle.title_id=titles.title_ID  FOR XML PATH(''), TYPE).value('.', 'varchar(max)')  ,1,1,'')    FROM titles  ORDER BY title_ID …which would be turned into an UPDATE … FROM script. UPDATE titles SET  typelist= ThisTaglistFROM     (SELECT title_ID, title, STUFF(    (SELECT ','+tagname.tag FROM titles thisTitle      INNER JOIN TagTitle ON titles.title_ID=TagTitle.Title_ID      INNER JOIN Tagname ON Tagname.TagName_ID=TagTitle.TagName_ID    WHERE ThisTitle.title_id=titles.title_ID    ORDER BY CASE WHEN tagname.tag=titles.[type] THEN 1 ELSE 0  END DESC    FOR XML PATH(''), TYPE).value('.', 'varchar(max)')    ,1,1,'')  AS ThisTagList  FROM titles)fINNER JOIN Titles ON f.title_ID=Titles.title_ID You’ll notice that it isn’t quite a round trip because the tags are in a different order, though we’ve managed to make sure that the primary tag is the first one as originally. So, we’ve improved the database for the poor book distributors using PUBS. It is not a major deal but you’ve got to be prepared to provide a migration script that will go both forwards and backwards. Ideally, database refactoring scripts should be able to go from any version to any other. Schema synchronization scripts can do this pretty easily, but no data synchronisation scripts can deal with serious refactoring jobs without the developers being able to specify how to deal with cases like this.

  Read the article

• Oracle?????????????~????????????????????

  - by Yusuke.Yamamoto

  RDBMS ???????·????????????????????????????????????????????????????????????????????????? ????????Oracle ?????????????????????????????????? Oracle Database ???????????????????????????????? Oracle????????????? ??????????????????????????????????? ?????????????????????????????? ????????????????????????????????????????????????? ??????????????????????????????????????????????????????????????? Oracle Database ?? Compile Time ???????? ?????????SQL??????Oracle Database ????????????????????????????????????????????????????????????????? ????????????????????????????????????????????? RDBMS ???????????????????? ???????????????? Oracle Database ????????????????????????? ?????????????Oracle Database ????????????????????????????RDBMS ???????????????????????????????????????????????????????????????????????????????????????????? ??????????????????????????????????????????????? ?????????????????????????????????????????? ?????????????????????????????????????????????????? ?????????????? Oracle Database ???????????????????????? Oracle Database ????????????????????? "Oracle ????????" ?????????? Sustaining Engineering?? ?(??? ???) ???????????????? Sustaining Engineering ????????????????????????Oracle Database ???????????????????????? Oracle????????????????????????! Oracle?????????????

  Read the article

• OJB Reference Descriptor 1:0 relationship? Should I set auto-retrieve to false?

  - by godzillasdm

  Hi, I am having an issue while using Apache OJB with Spring 2 inside my web app. I'm using OJB reference-descriptor with 2 foreign key properties. I have an object A (parent) and object B (referenced object). The thing is, for an object A, there may or may not be an object B. In the case where there is no object B to go with Object A, the object B seems to be instantiated (through Spring?) anyways. However, I am unable to access object B's members. Whenever I test if Object B == null, it always returns false even though there is no matching value in the database. Since this Object is never null, I figured I can test the object's member like so: if( objectb.getDocumentNumber == null) { return false; } However, I get an exception in the jsp: javax.servlet.jsp.el.ELException: An error occurred while getting property "documentNumber" from an instance class org.sample.pojo.Objectb$$EnhancerByCGLIB$$78022a2 and this exception in the debugger when it's creating the objectB: com.sun.jdi.InvocationException occurred invoking method. I am guessing that the reference-descriptor must be a 1:1+ relationship, instead of a 1:0+ relationship. I was wondering if I should set the property 'auto-retrieve' to false, and then use the PersistenceBroker.retrieveAllReferences(Object obj); method as directed. However, this method's return value is 'void', so I am guessing that Spring somehow creates, and sets the reference class for me. (Returning me back to the same issue I'm having.) I will need a way to test whether the reference object exists first. If not, don't call this retrieveAllReferences method, but I don't see how. Am I going about this all wrong? Does reference-descriptor not allow 1:0 relations? Any work around to my problem? Your suggestions are greatly appreciated!

  Read the article

• ?Oracle Database 12c????Information Lifecycle Management ILM?Storage Enhancements

  - by Liu Maclean(???)

  Oracle Database 12c????Information Lifecycle Management ILM ?????????Storage Enhancements ???????? Lifecycle Management ILM ????????? Automatic Data Placement ??????, ??ADP? ?????? 12c???????Datafile??? Online Move Datafile, ????????????????datafile???????,??????????????? ????(12.1.0.1)Automatic Data Optimization?heat map????????: ????????? (CDB)?????Automatic Data Optimization?heat map Row-level policies for ADO are not supported for Temporal Validity. Partition-level ADO and compression are supported if partitioned on the end-time columns. Row-level policies for ADO are not supported for in-database archiving. Partition-level ADO and compression are supported if partitioned on the ORA_ARCHIVE_STATE column. Custom policies (user-defined functions) for ADO are not supported if the policies default at the tablespace level. ADO does not perform checks for storage space in a target tablespace when using storage tiering. ADO is not supported on tables with object types or materialized views. ADO concurrency (the number of simultaneous policy jobs for ADO) depends on the concurrency of the Oracle scheduler. If a policy job for ADO fails more than two times, then the job is marked disabled and the job must be manually enabled later. Policies for ADO are only run in the Oracle Scheduler maintenance windows. Outside of the maintenance windows all policies are stopped. The only exceptions are those jobs for rebuilding indexes in ADO offline mode. ADO has restrictions related to moving tables and table partitions. ??????row,segment???????????ADO??,?????create table?alter table?????? ????ADO??,??????????????,???????????????? storage tier , ?????????storage tier?????????, ??????????????ADO??????????? segment?row??group? ?CREATE TABLE?ALERT TABLE???ILM???,??????????????????ADO policy? ??ILM policy???????????????? ??????? ????ADO policy, ?????alter table  ???????,?????????????? CREATE TABLE sales_ado (PROD_ID NUMBER NOT NULL, CUST_ID NUMBER NOT NULL, TIME_ID DATE NOT NULL, CHANNEL_ID NUMBER NOT NULL, PROMO_ID NUMBER NOT NULL, QUANTITY_SOLD NUMBER(10,2) NOT NULL, AMOUNT_SOLD NUMBER(10,2) NOT NULL ) ILM ADD POLICY COMPRESS FOR ARCHIVE HIGH SEGMENT AFTER 6 MONTHS OF NO ACCESS; SQL> SELECT SUBSTR(policy_name,1,24) AS POLICY_NAME, policy_type, enabled 2 FROM USER_ILMPOLICIES; POLICY_NAME POLICY_TYPE ENABLED -------------------- -------------------------- -------------- P41 DATA MOVEMENT YES ALTER TABLE sales MODIFY PARTITION sales_1995 ILM ADD POLICY COMPRESS FOR ARCHIVE HIGH SEGMENT AFTER 6 MONTHS OF NO ACCESS; SELECT SUBSTR(policy_name,1,24) AS POLICY_NAME, policy_type, enabled FROM USER_ILMPOLICIES; POLICY_NAME POLICY_TYPE ENABLE ------------------------ ------------- ------ P1 DATA MOVEMENT YES P2 DATA MOVEMENT YES /* You can disable an ADO policy with the following */ ALTER TABLE sales_ado ILM DISABLE POLICY P1; /* You can delete an ADO policy with the following */ ALTER TABLE sales_ado ILM DELETE POLICY P1; /* You can disable all ADO policies with the following */ ALTER TABLE sales_ado ILM DISABLE_ALL; /* You can delete all ADO policies with the following */ ALTER TABLE sales_ado ILM DELETE_ALL; /* You can disable an ADO policy in a partition with the following */ ALTER TABLE sales MODIFY PARTITION sales_1995 ILM DISABLE POLICY P2; /* You can delete an ADO policy in a partition with the following */ ALTER TABLE sales MODIFY PARTITION sales_1995 ILM DELETE POLICY P2; ILM ???????: ?????ILM ADP????,???????: ?????? ???? activity tracking, ????2????????,???????????????????: SEGMENT-LEVEL???????????????????? ROW-LEVEL????????,??????? ????????: 1??????? SEGMENT-LEVEL activity tracking ALTER TABLE interval_sales ILM  ENABLE ACTIVITY TRACKING SEGMENT ACCESS ???????INTERVAL_SALES??segment level  activity tracking,?????????????????? 2? ??????????? ALTER TABLE emp ILM ENABLE ACTIVITY TRACKING (CREATE TIME , WRITE TIME); 3????????? ALTER TABLE emp ILM ENABLE ACTIVITY TRACKING  (READ TIME); ?12.1.0.1.0?????? ??HEAT_MAP??????????, ?????system??session?????heap_map????????????? ?????????HEAT MAP??,? ALTER SYSTEM SET HEAT_MAP = ON; ?HEAT MAP??????,??????????????????????????  ??SYSTEM?SYSAUX????????????? ???????HEAT MAP??: ALTER SYSTEM SET HEAT_MAP = OFF; ????? HEAT_MAP????, ?HEAT_MAP??? ?????????????????????? ?HEAT_MAP?????????Automatic Data Optimization (ADO)??? ??ADO??,Heat Map ?????????? ????V$HEAT_MAP_SEGMENT ??????? HEAT MAP?? SQL> select * from V$heat_map_segment; no rows selected SQL> alter session set heat_map=on; Session altered. SQL> select * from scott.emp; EMPNO ENAME JOB MGR HIREDATE SAL COMM DEPTNO ---------- ---------- --------- ---------- --------- ---------- ---------- ---------- 7369 SMITH CLERK 7902 17-DEC-80 800 20 7499 ALLEN SALESMAN 7698 20-FEB-81 1600 300 30 7521 WARD SALESMAN 7698 22-FEB-81 1250 500 30 7566 JONES MANAGER 7839 02-APR-81 2975 20 7654 MARTIN SALESMAN 7698 28-SEP-81 1250 1400 30 7698 BLAKE MANAGER 7839 01-MAY-81 2850 30 7782 CLARK MANAGER 7839 09-JUN-81 2450 10 7788 SCOTT ANALYST 7566 19-APR-87 3000 20 7839 KING PRESIDENT 17-NOV-81 5000 10 7844 TURNER SALESMAN 7698 08-SEP-81 1500 0 30 7876 ADAMS CLERK 7788 23-MAY-87 1100 20 7900 JAMES CLERK 7698 03-DEC-81 950 30 7902 FORD ANALYST 7566 03-DEC-81 3000 20 7934 MILLER CLERK 7782 23-JAN-82 1300 10 14 rows selected. SQL> select * from v$heat_map_segment; OBJECT_NAME SUBOBJECT_NAME OBJ# DATAOBJ# TRACK_TIM SEG SEG FUL LOO CON_ID -------------------- -------------------- ---------- ---------- --------- --- --- --- --- ---------- EMP 92997 92997 23-JUL-13 NO NO YES NO 0 ??v$heat_map_segment???,?v$heat_map_segment??????????????X$HEATMAPSEGMENT V$HEAT_MAP_SEGMENT displays real-time segment access information. Column Datatype Description OBJECT_NAME VARCHAR2(128) Name of the object SUBOBJECT_NAME VARCHAR2(128) Name of the subobject OBJ# NUMBER Object number DATAOBJ# NUMBER Data object number TRACK_TIME DATE Timestamp of current activity tracking SEGMENT_WRITE VARCHAR2(3) Indicates whether the segment has write access: (YES or NO) SEGMENT_READ VARCHAR2(3) Indicates whether the segment has read access: (YES or NO) FULL_SCAN VARCHAR2(3) Indicates whether the segment has full table scan: (YES or NO) LOOKUP_SCAN VARCHAR2(3) Indicates whether the segment has lookup scan: (YES or NO) CON_ID NUMBER The ID of the container to which the data pertains. Possible values include:   0: This value is used for rows containing data that pertain to the entire CDB. This value is also used for rows in non-CDBs. 1: This value is used for rows containing data that pertain to only the root n: Where n is the applicable container ID for the rows containing data The Heat Map feature is not supported in CDBs in Oracle Database 12c, so the value in this column can be ignored. ??HEAP MAP??????????????????,????DBA_HEAT_MAP_SEGMENT???????? ???????HEAT_MAP_STAT$?????? ??Automatic Data Optimization??????: ????1: SQL> alter system set heat_map=on; ?????? ????????????? scott?? http://www.askmaclean.com/archives/scott-schema-script.html SQL> grant all on dbms_lock to scott; ????? SQL> grant dba to scott; ????? @ilm_setup_basic C:\APP\XIANGBLI\ORADATA\MACLEAN\ilm.dbf @tktgilm_demo_env_setup SQL> connect scott/tiger ; ???? SQL> select count(*) from scott.employee; COUNT(*) ---------- 3072 ??? 1 ?? SQL> set serveroutput on SQL> exec print_compression_stats('SCOTT','EMPLOYEE'); Compression Stats ------------------ Uncmpressed : 3072 Adv/basic compressed : 0 Others : 0 PL/SQL ???????? ???????3072?????? ????????? ????policy ???????????? alter table employee ilm add policy row store compress advanced row after 3 days of no modification / SQL> set serveroutput on SQL> execute list_ilm_policies; -------------------------------------------------- Policies defined for SCOTT -------------------------------------------------- Object Name------ : EMPLOYEE Subobject Name--- : Object Type------ : TABLE Inherited from--- : POLICY NOT INHERITED Policy Name------ : P1 Action Type------ : COMPRESSION Scope------------ : ROW Compression level : ADVANCED Tier Tablespace-- : Condition type--- : LAST MODIFICATION TIME Condition days--- : 3 Enabled---------- : YES -------------------------------------------------- PL/SQL ???????? SQL> select sysdate from dual; SYSDATE -------------- 29-7? -13 SQL> execute set_back_chktime(get_policy_name('EMPLOYEE',null,'COMPRESSION','ROW','ADVANCED',3,null,null),'EMPLOYEE',null,6); Object check time reset ... -------------------------------------- Object Name : EMPLOYEE Object Number : 93123 D.Object Numbr : 93123 Policy Number : 1 Object chktime : 23-7? -13 08.13.42.000000 ?? Distnt chktime : 0 -------------------------------------- PL/SQL ???????? ?policy?chktime???6??, ????set_back_chktime???????????????“????”?,?????????,???????? ?????? alter system flush buffer_cache; alter system flush buffer_cache; alter system flush shared_pool; alter system flush shared_pool; SQL> execute set_window('MONDAY_WINDOW','OPEN'); Set Maint. Window OPEN ----------------------------- Window Name : MONDAY_WINDOW Enabled? : TRUE Active? : TRUE ----------------------------- PL/SQL ???????? SQL> exec dbms_lock.sleep(60) ; PL/SQL ???????? SQL> exec print_compression_stats('SCOTT', 'EMPLOYEE'); Compression Stats ------------------ Uncmpressed : 338 Adv/basic compressed : 2734 Others : 0 PL/SQL ???????? ??????????????? Adv/basic compressed : 2734 ??????? SQL> col object_name for a20 SQL> select object_id,object_name from dba_objects where object_name='EMPLOYEE'; OBJECT_ID OBJECT_NAME ---------- -------------------- 93123 EMPLOYEE SQL> execute list_ilm_policy_executions ; -------------------------------------------------- Policies execution details for SCOTT -------------------------------------------------- Policy Name------ : P22 Job Name--------- : ILMJOB48 Start time------- : 29-7? -13 08.37.45.061000 ?? End time--------- : 29-7? -13 08.37.48.629000 ?? ----------------- Object Name------ : EMPLOYEE Sub_obj Name----- : Obj Type--------- : TABLE ----------------- Exec-state------- : SELECTED FOR EXECUTION Job state-------- : COMPLETED SUCCESSFULLY Exec comments---- : Results comments- : --- -------------------------------------------------- PL/SQL ???????? ILMJOB48?????policy?JOB,?12.1.0.1??J00x???? ?MMON_SLAVE???M00x???15????????? select sample_time,program,module,action from v$active_session_history where action ='KDILM background EXEcution' order by sample_time; 29-7? -13 08.16.38.369000000 ?? ORACLE.EXE (M000) MMON_SLAVE KDILM background EXEcution 29-7? -13 08.17.38.388000000 ?? ORACLE.EXE (M000) MMON_SLAVE KDILM background EXEcution 29-7? -13 08.17.39.390000000 ?? ORACLE.EXE (M000) MMON_SLAVE KDILM background EXEcution 29-7? -13 08.23.38.681000000 ?? ORACLE.EXE (M002) MMON_SLAVE KDILM background EXEcution 29-7? -13 08.32.38.968000000 ?? ORACLE.EXE (M000) MMON_SLAVE KDILM background EXEcution 29-7? -13 08.33.39.993000000 ?? ORACLE.EXE (M003) MMON_SLAVE KDILM background EXEcution 29-7? -13 08.33.40.993000000 ?? ORACLE.EXE (M003) MMON_SLAVE KDILM background EXEcution 29-7? -13 08.36.40.066000000 ?? ORACLE.EXE (M000) MMON_SLAVE KDILM background EXEcution 29-7? -13 08.37.42.258000000 ?? ORACLE.EXE (M000) MMON_SLAVE KDILM background EXEcution 29-7? -13 08.37.43.258000000 ?? ORACLE.EXE (M000) MMON_SLAVE KDILM background EXEcution 29-7? -13 08.37.44.258000000 ?? ORACLE.EXE (M000) MMON_SLAVE KDILM background EXEcution 29-7? -13 08.38.42.386000000 ?? ORACLE.EXE (M001) MMON_SLAVE KDILM background EXEcution select distinct action from v$active_session_history where action like 'KDILM%' KDILM background CLeaNup KDILM background EXEcution SQL> execute set_window('MONDAY_WINDOW','CLOSE'); Set Maint. Window CLOSE ----------------------------- Window Name : MONDAY_WINDOW Enabled? : TRUE Active? : FALSE ----------------------------- PL/SQL ???????? SQL> drop table employee purge ; ????? ???? ????? spool ilm_usecase_1_cleanup.lst @ilm_demo_cleanup ; spool off

  Read the article

< Previous Page | 101 102 103 104 105 106 107 108 109 110 111 112  | Next Page >