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  • Move SQL-Server Database with zero downtime

    - by Uwe
    Hello, how is it possible to move a sql 2005 db to a different sql 2008(!) server without any downtime? The system is 24/7 and has to be moved to a differen server with a different storage. We tried copy database, but that does not keep the whole db synchronus at the end of the process but only tablewise.

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  • Retrieve MS SQL database or table struture in XML

    - by clutch
    Is there a way to export the database schema in well formed XML of a MS 2000 SQL Server. I'm looking for just the structure not the data and the more detailed the better. The XML may be used in a migration processes. I'm more familiar with MySQL then with SQL Server so please be detailed if you hav time. Thanks

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  • Vmware cpu allocation for a spiking database server

    - by user1552172
    I have a database server with many poorly written queries that causes the sql server to spike then drop constantly ( a massive start from scratch is happening). I need to know if the cpu allocation on the vm to expand as needed is best practice for a case like this. I am wondering if the esxi platform cant expand as fast as the spikes happen. I am curious what is best practice for vm cpu allocation on sql server (with horribly written queries)

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  • Remote access to Microsoft Dynamics NAV (C/Side) with native non-SQL database

    - by Joannes Vermorel
    I am facing a company that have a fairly recent Microsoft Dynamics NAV (C/Side) setup that comes with a non-SQL storage system called the native database server. I would need to be remotely connect to this database, and perform what would equate to SQL queries with very modest needs (no join, no complex filtering). I am rather ignorant of this technology, does someone knows to how make remote queries to this ERP?

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  • Need help recovering a corrupt SQL database

    - by user570079
    I have a very special case that I have been working on for several days. I have a very large SQL Server 2008 database (about 2 TB) that contains 500 filegroups to support very large partitioned tables. Recently we had a catastophic failure on one of the drive and lost several filegroups and the database became in-accessible. We have been doing filegroup backups on a daily basis, but due to other issues, we lost our most recent backup of the log and the primary filegroup. We have all the data backed up but the primary filegroup backup is old. There have been no schema changes since the primary filegroup backup, but the lsn's are now all out of sync and we cannot recover the data. I have tried everything I could think of (and have tried just about every trick and hack I could google) but I still end up at the same point where I get messages saying that the files for filegroup x do not match the primary filegroup. I am now at the point of trying to edit the system tables (we have a separate temporary environment to do this so we are not worried about corrupting any production databases). I have tried updated sys.sysdbreg, sys.sysbrickfiles, and sys.sysprufiles to try to trick SQL into thinking all the files are online, but a "Select * From OPENROWSET(TABLE DBPROP, 5)" shows a different database state from what I see in sys.sysdbreg. I am now thinking I need to somehow edit the headers of the actual data files to try to line up the lsn's with the primary. I appreciate any help anyone can give me here, but please do not respond with things like "you are not supposed to do edit mdf, ndf files...." or "see msdn article....", etc. This is an advanced emergency case and I need a real hack so we can just get to the data in this corrupt database and export to a fresh new database. I know there is a way to do this, but not knowing what the DBPROP system functions does (i.e. does it look at system tables or does it actually open the file) is keeping me from trying to figure out how to fool SQL into allowing me to read these files. Thanks for any help.

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  • Retrieve MS SQL database or table structure in XML

    - by clutch
    Is there a way to export the database schema in well formed XML of a MS 2000 SQL Server. I'm looking for just the structure not the data and the more detailed the better. The XML may be used in a migration processes. I'm more familiar with MySQL then with SQL Server so please be detailed if you have time. Thanks

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  • Secure external connection to SQL Server (from third party software)

    - by Bart
    I have a SQL Express 2008 R2 server running on a server in an internal lan network. A few databases are used by some third party software to store data. A SQL-Server user is used by this application to connect to the database. Now I need to access this database using a local installation of the software from an external pc. In this particular case a VPN connection is not the solution I am looking for. I have access to an external linux server, so I tried ssh tunneling from the windows server to the linux server and use the external pc to tunnel it back from the linux server to the client, but this is working very very slow. What are my other options to allow this external connection in a safe way?

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  • Help! The log file for database 'tempdb' is full. Back up the transaction log for the database to fr

    - by michael.lukatchik
    We're running SQL Server 2000. In our database, we have an "Orders" table with approximately 750,000 rows. We can perform simple SELECT statements on this table. However, when we want to run a query like SELECT TOP 100 * FROM Orders ORDER BY Date_Ordered DESC, we receive the following message: Error: 9002, Severity: 17, State: 6 The log file for database 'tempdb' is full. Back up the transaction log for the database to free up some log space. We have other tables in our database which are similar in size of the amount of records that are in the tables (i.e. 700,000 records). On these tables, we can run any queries we'd like and we never receive a message about 'tempdb being full'. To resolve this, we've backed up our database, shrunk the actual database and also shrunk the database and files in the tempdb system database, but this hasn't resolved the issue. The size of our log file is set to autogrow. We're not sure where to go next. Are there any ideas why we still might be receiving this message? Error: 9002, Severity: 17, State: 6 The log file for database 'tempdb' is full. Back up the transaction log for the database to free up some log space.

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  • Windows Server task manager displays much higher memory use than sum of all processes' working set s

    - by Sleepless
    I have a 16 GB Windows Server 2008 x64 machine mostly running SQL Server 2008. The free memory as seen in Task Manager is very low (128 MB at the moment), i.e. about 15.7 GB are used. So far, so good. Now when I try to narrow down the process(es) using the most memory I get confused: None of the processes have more than 200MB Working Set Size as displayed in the 'Processes' tab of Task Manager. Well, maybe the Working Set Size isn't the relevant counter? To figure that out I used a PowerShell command [1] to sum up each individual property of the process object in sort of a brute force approach - surely one of them must add up to the 15.7 GB, right? Turns out none of them does, with the closest being VirtualMemorySize (around 12.7 GB) and PeakVirtualMemorySize (around 14.7 GB). WTF? To put it another way: Which of the numerous memory related process information is the "correct" one, i.e. counts towards the server's physical memory as displayed in the Task Manager's 'Performance' tab? Thank you all! [1] $erroractionpreference="silentlycontinue"; get-process | gm | where-object {$.membertype -eq "Property"} | foreach-object {$.name; (get-process | measure-object -sum $_.name ).sum / 1MB}

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  • Windows 2008 as home file server and more

    - by Christian W
    I currently have a freenas-unit as a NAS, and a Win2k8R2-unit as server. However I would like to consolidate these to units in one. What I really like about the freenas-unit is the ZFS filesystem. And the only reason I care about the ZFS filesystem is the easy way I can grow an existing filesystem just by inserting a new drive. How would this work in Win2k8? If I setup my unit with a separate drive as C: and a 1TB drive as D:. The D: would then be segmented into d:\Videos d:\Music d:\Pictures. When everything gets close to filling the storage-drive, I would like to expand the storage, but I wouldn't want to have E:\Videos or d:\Videos2 (using the NTFS folder mount thingy). I still want all my Videos to reside in D:\Videos and I want the OS to decide which drive it's going to be stored on... Some kind of on-the-fly jbod expansion :) Is this at all possible in Windows 2008?

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  • Setting up Raid 1 Array for Home Server

    - by user1048116
    I'm not sure if this is even possible, but it's worth asking on here! Essentially I have a old machine at home (well, not old hardware wise, but I recently built a new gaming rig), which I decided to install a copy of W2008 R2 on and use as a file/backup server and media center'ish machine. As of now, it has a single drive partitioned into C and D, with D being the Data partition. I have happened to find an old 1TB SATA drive lying around at home, and was wondering if it's possible to setup a Raid 1 array in my rig within Windows without needing to lose everything on my first drive (or maybe even just mirror a specific partition, say the Data partition, as this is just what stores my photos etc). Maybe this isn't possible, but you never know :) Regards, T.C

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  • SQL Server 2005/2008 Licensing Decision

    - by Hakim
    Hello, I have purchased a dedicated server from a reputable Hosting company. They only have Windows Server 2008 OS installed on it and NO Sql server. Server Configuration is Intel Dual core Processor with 2GB of RAM and 100GB HDD. I wanted to host my web services on that server which will be using the MS SQL Server 2005 at the backend.There are multiple web services and each using a different Database. Microsoft has CAL basis Licensing , Which I understand is based on number of users accessing the database directly ( I may be wrong ) . But my users will be accessing the webservice and no direct connection to the database as such. Yes but the number of users accessing the web server cannot be known and is not under my control. Which Licensing is best suited for this kind of setup ? I don't need analysing and BI services right now ,but i may want to upgrade that in future may be. Any help will be appreciated. Thanks

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  • How to implement EntityDataSource Where IN entity sql clause

    - by TonyS
    I want to pass a number of values into a parameter of the EntityDataSource, e.g.: Where="it.ORDER_ID IN {@OrderIdList}" (this is a property on the EntityDataSource) <WhereParameters> <asp:ControlParameter Name="OrderIdList" Type="Int16" ControlID="OrderFilterControl" PropertyName="OrderIdList" /> </WhereParameters> This doesn't work as ORDER_ID is of type int32 and I need to pass in multiple values, e.g. {1,2,3} etc The next thing I tried was setting the Where clause in code-behind and this all works except I can't get data binding on DropDownLists to work. By this I mean no value is returned from the bound dropdownlists in the EntityDataSource Updating Event. My ideal solution would be to use a WhereParameter on the EntityDataSource but any help is appreciated. Thanks, Tony. A complete code example follows using the AdventureWorks db: Public Class EntityDataSourceWhereInClause Inherits System.Web.UI.Page Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load CustomersEntityDataSource.Where = WhereClause ''# reset after each postback as its lost otherwise End Sub Private Sub cmdFilterCustomers_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles cmdFilterCustomers.Click Dim CustomerIdList As New Generic.List(Of Int32) For Each item As ListItem In CustomerIdCheckBoxList.Items If item.Selected Then CustomerIdList.Add(item.Value) End If Next Dim CustomerCsvList As String = String.Join(", ", CustomerIdList.Select(Function(o) o.ToString()).ToArray()) WhereClause = "it.CustomerID IN {" & CustomerCsvList & "}" CustomersEntityDataSource.Where = WhereClause FormView1.PageIndex = 0 End Sub ''# save between postbacks the custom Where IN clause Public Property WhereClause() As String Get Return ViewState("WhereClause") End Get Set(ByVal value As String) ViewState.Add("WhereClause", value) End Set End Property Private Sub CustomersEntityDataSource_Updating(ByVal sender As Object, ByVal e As System.Web.UI.WebControls.EntityDataSourceChangingEventArgs) Handles CustomersEntityDataSource.Updating Dim c = CType(e.Entity, EntityFrameworkTest.Customer) If c.Title.Length = 0 Then Response.Write("Title is empty string, so will save like this!") End If End Sub End Class <%@ Page Language="vb" AutoEventWireup="false" CodeBehind="EntityDataSourceWhereInClause.aspx.vb" Inherits="EntityFrameworkTest.EntityDataSourceWhereInClause" %> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head runat="server"> <title></title> </head> <body> <form id="form1" runat="server"> <%''# filter control %> <div> <asp:EntityDataSource ID="CustomerIdListEntityDataSource" runat="server" ConnectionString="name=AdventureWorksLT2008Entities" DefaultContainerName="AdventureWorksLT2008Entities" EnableFlattening="False" EntitySetName="Customers" Select="it.[CustomerID]" OrderBy="it.[CustomerID]"> </asp:EntityDataSource> <asp:CheckBoxList ID="CustomerIdCheckBoxList" runat="server" DataSourceID="CustomerIdListEntityDataSource" DataTextField="CustomerID" DataValueField="CustomerID" RepeatDirection="Horizontal"> </asp:CheckBoxList> <asp:Button ID="cmdFilterCustomers" runat="server" Text="Apply Filter" /> </div> <% ''# you get this error passing in CSV in the where clause ''# The element type 'Edm.Int32' and the CollectionType 'Transient.collection[Edm.String(Nullable=True,DefaultValue=,MaxLength=,Unicode=,FixedLength=)]' are not compatible. The IN expression only supports entity, primitive, and reference types. Near WHERE predicate, line 6, column 15. ''# so have coded it manually in code-behind Where="it.CustomerID IN {@OrderIdList}" %> <asp:EntityDataSource ID="CustomersEntityDataSource" runat="server" ConnectionString="name=AdventureWorksLT2008Entities" DefaultContainerName="AdventureWorksLT2008Entities" EnableFlattening="False" EnableUpdate="True" EntitySetName="Customers" AutoGenerateOrderByClause="false"> </asp:EntityDataSource> <%''# updating works with DropDownLists until the Where clause is set in code %> <asp:FormView ID="FormView1" runat="server" AllowPaging="True" CellPadding="4" DataKeyNames="CustomerID" DataSourceID="CustomersEntityDataSource" ForeColor="#333333"> <EditItemTemplate> CustomerID: <asp:Label ID="CustomerIDLabel1" runat="server" Text='<%# Eval("CustomerID") %>' /> <br /> NameStyle: <asp:CheckBox ID="NameStyleCheckBox" runat="server" Checked='<%# Bind("NameStyle") %>' /> <br /> Title: <%''# the SelectedValue is not Bound to the EF object if the Where clause is updated in code-behind %> <asp:DropDownList ID="ddlTitleBound" runat="server" DataSourceID="TitleEntityDataSource" DataTextField="Title" DataValueField="Title" AutoPostBack="false" AppendDataBoundItems="true" SelectedValue='<%# Bind("Title") %>'> </asp:DropDownList> <asp:EntityDataSource ID="TitleEntityDataSource" runat="server" ConnectionString="name=AdventureWorksLT2008Entities" DefaultContainerName="AdventureWorksLT2008Entities" EnableFlattening="False" EntitySetName="Customers" Select="it.[Title]" GroupBy="it.[Title]" ViewStateMode="Enabled"> </asp:EntityDataSource> <br /> FirstName: <asp:TextBox ID="FirstNameTextBox" runat="server" Text='<%# Bind("FirstName") %>' /> <br /> MiddleName: <asp:TextBox ID="MiddleNameTextBox" runat="server" Text='<%# Bind("MiddleName") %>' /> <br /> LastName: <asp:TextBox ID="LastNameTextBox" runat="server" Text='<%# Bind("LastName") %>' /> <br /> Suffix: <asp:TextBox ID="SuffixTextBox" runat="server" Text='<%# Bind("Suffix") %>' /> <br /> CompanyName: <asp:TextBox ID="CompanyNameTextBox" runat="server" Text='<%# Bind("CompanyName") %>' /> <br /> SalesPerson: <asp:TextBox ID="SalesPersonTextBox" runat="server" Text='<%# Bind("SalesPerson") %>' /> <br /> EmailAddress: <asp:TextBox ID="EmailAddressTextBox" runat="server" Text='<%# Bind("EmailAddress") %>' /> <br /> Phone: <asp:TextBox ID="PhoneTextBox" runat="server" Text='<%# Bind("Phone") %>' /> <br /> PasswordHash: <asp:TextBox ID="PasswordHashTextBox" runat="server" Text='<%# Bind("PasswordHash") %>' /> <br /> PasswordSalt: <asp:TextBox ID="PasswordSaltTextBox" runat="server" Text='<%# Bind("PasswordSalt") %>' /> <br /> rowguid: <asp:TextBox ID="rowguidTextBox" runat="server" Text='<%# Bind("rowguid") %>' /> <br /> ModifiedDate: <asp:TextBox ID="ModifiedDateTextBox" runat="server" Text='<%# Bind("ModifiedDate") %>' /> <br /> <asp:LinkButton ID="UpdateButton" runat="server" CausesValidation="True" CommandName="Update" Text="Update" /> &nbsp;<asp:LinkButton ID="UpdateCancelButton" runat="server" CausesValidation="False" CommandName="Cancel" Text="Cancel" /> </EditItemTemplate> <EditRowStyle BackColor="#999999" /> <FooterStyle BackColor="#5D7B9D" Font-Bold="True" ForeColor="White" /> <HeaderStyle BackColor="#5D7B9D" Font-Bold="True" ForeColor="White" /> <ItemTemplate> CustomerID: <asp:Label ID="CustomerIDLabel" runat="server" Text='<%# Eval("CustomerID") %>' /> <br /> NameStyle: <asp:CheckBox ID="NameStyleCheckBox" runat="server" Checked='<%# Bind("NameStyle") %>' Enabled="false" /> <br /> Title: <asp:Label ID="TitleLabel" runat="server" Text='<%# Bind("Title") %>' /> <br /> FirstName: <asp:Label ID="FirstNameLabel" runat="server" Text='<%# Bind("FirstName") %>' /> <br /> MiddleName: <asp:Label ID="MiddleNameLabel" runat="server" Text='<%# Bind("MiddleName") %>' /> <br /> LastName: <asp:Label ID="LastNameLabel" runat="server" Text='<%# Bind("LastName") %>' /> <br /> Suffix: <asp:Label ID="SuffixLabel" runat="server" Text='<%# Bind("Suffix") %>' /> <br /> CompanyName: <asp:Label ID="CompanyNameLabel" runat="server" Text='<%# Bind("CompanyName") %>' /> <br /> SalesPerson: <asp:Label ID="SalesPersonLabel" runat="server" Text='<%# Bind("SalesPerson") %>' /> <br /> EmailAddress: <asp:Label ID="EmailAddressLabel" runat="server" Text='<%# Bind("EmailAddress") %>' /> <br /> Phone: <asp:Label ID="PhoneLabel" runat="server" Text='<%# Bind("Phone") %>' /> <br /> PasswordHash: <asp:Label ID="PasswordHashLabel" runat="server" Text='<%# Bind("PasswordHash") %>' /> <br /> PasswordSalt: <asp:Label ID="PasswordSaltLabel" runat="server" Text='<%# Bind("PasswordSalt") %>' /> <br /> rowguid: <asp:Label ID="rowguidLabel" runat="server" Text='<%# Bind("rowguid") %>' /> <br /> ModifiedDate: <asp:Label ID="ModifiedDateLabel" runat="server" Text='<%# Bind("ModifiedDate") %>' /> <br /> <asp:LinkButton ID="EditButton" runat="server" CausesValidation="False" CommandName="Edit" Text="Edit" /> </ItemTemplate> <PagerSettings Position="Top" /> <PagerStyle BackColor="#284775" ForeColor="White" HorizontalAlign="Center" /> <RowStyle BackColor="#F7F6F3" ForeColor="#333333" /> </asp:FormView> </form>

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  • Is there any reason not to go directly from client-side Javascript to a database?

    - by Chris Smith
    So, let's say I'm going to build a Stack Exchange clone and I decide to use something like CouchDB as my backend store. If I use their built-in authentication and database-level authorization, is there any reason not to allow the client-side Javascript to write directly to the publicly available CouchDB server? Since this is basically a CRUD application and the business logic consists of "Only the author can edit their post" I don't see much of a need to have a layer between the client-side stuff and the database. I would simply use validation on the CouchDB side to make sure someone isn't putting in garbage data and make sure that permissions are set properly so that users can only read their own _user data. The rendering would be done client-side by something like AngularJS. In essence you could just have a CouchDB server and a bunch of "static" pages and you're good to go. You wouldn't need any kind of server-side processing, just something that could serve up the HTML pages. Opening my database up to the world seems wrong, but in this scenario I can't think of why as long as permissions are set properly. It goes against my instinct as a web developer, but I can't think of a good reason. So, why is this a bad idea? EDIT: Looks like there is a similar discussion here: Writing Web "server less" applications EDIT: Awesome discussion so far, and I appreciate everyone's feedback! I feel like I should add a few generic assumptions instead of calling out CouchDB and AngularJS specifically. So let's assume that: The database can authenticate users directly from its hidden store All database communication would happen over SSL Data validation can (but maybe shouldn't?) be handled by the database The only authorization we care about other than admin functions is someone only being allowed to edit their own post We're perfectly fine with everyone being able to read all data (EXCEPT user records which may contain password hashes) Administrative functions would be restricted by database authorization No one can add themselves to an administrator role The database is relatively easy to scale There is little to no true business logic; this is a basic CRUD app

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  • Parsing T-SQL – The easy way

    - by Dave Ballantyne
    Every once in a while, I hit an issue that would require me to interrogate/parse some T-SQL code.  Normally, I would shy away from this and attempt to solve the problem in some other way.  I have written parsers before in the the past using LEX and YACC, and as much fun and awesomeness that path is,  I couldnt justify the time it would take. However, this week I have been faced with just such an issue and at the back of my mind I can remember reading through the SQLServer 2012 feature pack and seeing something called “Microsoft SQL Server 2012 Transact-SQL Language Service “.  This is described there as : “The SQL Server Transact-SQL Language Service is a component based on the .NET Framework which provides parsing validation and IntelliSense services for Transact-SQL for SQL Server 2012, SQL Server 2008 R2, and SQL Server 2008. “ Sounds just what I was after.  Documentation is very scant on this so dont take what follows as best practice or best use, just a practice and a use. Knowing what I was sort of looking for something, I found the relevant assembly in the gac which is the simply named ,’Microsoft.SqlServer.Management.SqlParser’. Even knowing that you wont find much in terms of documentation if you do a web-search, but you will find the MSDN documentation that list the members and methods etc… The “scanner”  class sounded the most appropriate for my needs as that is described as “Scans Transact-SQL searching for individual units of code or tokens.”. After a bit of poking, around the code i ended up with was something like [System.Reflection.Assembly]::LoadWithPartialName("Microsoft.SqlServer.Management.SqlParser") | Out-Null $ParseOptions = New-Object Microsoft.SqlServer.Management.SqlParser.Parser.ParseOptions $ParseOptions.BatchSeparator = 'GO' $Parser = new-object Microsoft.SqlServer.Management.SqlParser.Parser.Scanner($ParseOptions) $Sql = "Create Procedure MyProc as Select top(10) * from dbo.Table" $Parser.SetSource($Sql,0) $Token=[Microsoft.SqlServer.Management.SqlParser.Parser.Tokens]::TOKEN_SET $Start =0 $End = 0 $State =0 $IsEndOfBatch = $false $IsMatched = $false $IsExecAutoParamHelp = $false while(($Token = $Parser.GetNext([ref]$State ,[ref]$Start, [ref]$End, [ref]$IsMatched, [ref]$IsExecAutoParamHelp ))-ne [Microsoft.SqlServer.Management.SqlParser.Parser.Tokens]::EOF) { try{ ($TokenPrs =[Microsoft.SqlServer.Management.SqlParser.Parser.Tokens]$Token) | Out-Null $TokenPrs $Sql.Substring($Start,($end-$Start)+1) }catch{ $TokenPrs = $null } } As you can see , the $Sql variable holds the sql to be parsed , that is pushed into the $Parser object using SetSource,  and then we will use GetNext until the EOF token is returned.  GetNext will also return the Start and End character positions within the source string of the parsed text. This script’s output is : TOKEN_CREATE Create TOKEN_PROCEDURE Procedure TOKEN_ID MyProc TOKEN_AS as TOKEN_SELECT Select TOKEN_TOP top TOKEN_INTEGER 10 TOKEN_FROM from TOKEN_ID dbo TOKEN_TABLE Table note that the ‘(‘, ‘)’  and ‘*’ characters have returned a token type that is not present in the Microsoft.SqlServer.Management.SqlParser.Parser.Tokens Enum that has caused an error which has been caught in the catch block.  Fun, Fun ,Fun , Simple T-SQL Parsing.  Hope this helps someone in the same position,  let me know how you get on.

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  • Single logical SQL Server possible from multiple physical servers?

    - by TuffyIsHere
    Hi, With Microsoft SQL Server 2005, is it possible to combine the processing power of multiple physical servers into a single logical sql server? Is it possible on SQL Server 2008? I'm thinking, if the database files were located on a SAN and somehow one of the sql servers acted as a kind of master, then processing could be spread out over multiple physical servers, for instance even allowing simultaneous updates where there was no overlap, and in the case of read-only queries on unlocked tables no limit. We have an application that is limited by the speed of our sql server, and probably stuck with server 2005 for now. Is the only option to get a single more powerful physical server? Sorry I'm not an expert, I'm not sure if the question is a stupid one. TIA

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  • ?12c database ????Adaptive Execution Plans ????????

    - by Liu Maclean(???)
    12c R1 ????SQL??????- Adaptive Execution Plans ????????,???????optimizer ??????(runtime)???????????????, ????????????????????? SQL???????? ????????????, ?????????????????????????????????????????????????????????????adaptive plan ????????????????????????????????????,?????subplan???????????????????? ??????, ???????? ???????????????,?????????, ?????? ???????????????”???”????, ???????????????????buffer ???????  ????????????,?????,??????????????????? ???optimizer ?????????????????????????,?????????????????????????????????????????plan???? ??12C?????????????, ???????????????????,?????? ???????????? ????????????2???: Dynamic Plans????: ???????????????????????;??????,???optimizer??????????subplans??????????????, ???????????????????,?????????????? Reoptimization????: ?Dynamic Plans????,Reoptimization??????????????????????Reoptimization??,?????????????????????????,??reoptimization????? OPTIMIZER_ADAPTIVE_REPORTING_ONLY ???? report-only????????????????TRUE,?????????report-only????,???????????????,??????????????? Dynamic Plans ??????????????,????????????????????????, ?????????????,???????????,????????????????????????????????????????? ?????????????final plan??????????????default plan, ??final plan?default plan???????,????????????? subplan ???????????????,???????????????????????? ??????,???????statistics collector ?buffer???????????statistics collector?????????????????,???????????????????????????? ?????????????????????????????????????????,??????????,?????????????? ???????????,???????buffer???? ???????????????,?????????????????????????????,??????buffer,??????final plan? ????????,???????????????????????,????????????????? ?V$SQL??????IS_RESOLVED_DYNAMIC_PLAN??????????final plan???default plan? ??????dynamic plan ???????SQL PLAN directives?????? declare cursor PLAN_DIRECTIVE_IDS is select directive_id from DBA_SQL_PLAN_DIRECTIVES; begin for z in PLAN_DIRECTIVE_IDS loop DBMS_SPD.DROP_SQL_PLAN_DIRECTIVE(z.directive_id); end loop; end; / explain plan for select /*MALCEAN*/ product_name from oe.order_items o, oe.product_information p where o.unit_price=15 and quantity>1 and p.product_id=o.product_id; select * from table(dbms_xplan.display()); Plan hash value: 1255158658 www.askmaclean.com ------------------------------------------------------------------------------------------------------- | Id | Operation | Name | Rows | Bytes | Cost (%CPU)| Time | ------------------------------------------------------------------------------------------------------- | 0 | SELECT STATEMENT | | 4 | 128 | 7 (0)| 00:00:01 | | 1 | NESTED LOOPS | | | | | | | 2 | NESTED LOOPS | | 4 | 128 | 7 (0)| 00:00:01 | |* 3 | TABLE ACCESS FULL | ORDER_ITEMS | 4 | 48 | 3 (0)| 00:00:01 | |* 4 | INDEX UNIQUE SCAN | PRODUCT_INFORMATION_PK | 1 | | 0 (0)| 00:00:01 | | 5 | TABLE ACCESS BY INDEX ROWID| PRODUCT_INFORMATION | 1 | 20 | 1 (0)| 00:00:01 | ------------------------------------------------------------------------------------------------------- Predicate Information (identified by operation id): --------------------------------------------------- 3 - filter("O"."UNIT_PRICE"=15 AND "QUANTITY">1) 4 - access("P"."PRODUCT_ID"="O"."PRODUCT_ID") alter session set events '10053 trace name context forever,level 1'; OR alter session set events 'trace[SQL_Plan_Directive] disk highest'; select /*MALCEAN*/ product_name from oe.order_items o, oe.product_information p where o.unit_price=15 and quantity>1 and p.product_id=o.product_id; ---------------------------------------------------------------+-----------------------------------+ | Id | Operation | Name | Rows | Bytes | Cost | Time | ---------------------------------------------------------------+-----------------------------------+ | 0 | SELECT STATEMENT | | | | 7 | | | 1 | HASH JOIN | | 4 | 128 | 7 | 00:00:01 | | 2 | NESTED LOOPS | | | | | | | 3 | NESTED LOOPS | | 4 | 128 | 7 | 00:00:01 | | 4 | STATISTICS COLLECTOR | | | | | | | 5 | TABLE ACCESS FULL | ORDER_ITEMS | 4 | 48 | 3 | 00:00:01 | | 6 | INDEX UNIQUE SCAN | PRODUCT_INFORMATION_PK| 1 | | 0 | | | 7 | TABLE ACCESS BY INDEX ROWID | PRODUCT_INFORMATION | 1 | 20 | 1 | 00:00:01 | | 8 | TABLE ACCESS FULL | PRODUCT_INFORMATION | 1 | 20 | 1 | 00:00:01 | ---------------------------------------------------------------+-----------------------------------+ Predicate Information: ---------------------- 1 - access("P"."PRODUCT_ID"="O"."PRODUCT_ID") 5 - filter(("O"."UNIT_PRICE"=15 AND "QUANTITY">1)) 6 - access("P"."PRODUCT_ID"="O"."PRODUCT_ID") ===================================== SPD: BEGIN context at statement level ===================================== Stmt: ******* UNPARSED QUERY IS ******* SELECT /*+ OPT_ESTIMATE (@"SEL$1" JOIN ("P"@"SEL$1" "O"@"SEL$1") ROWS=13.000000 ) OPT_ESTIMATE (@"SEL$1" TABLE "O"@"SEL$1" ROWS=13.000000 ) */ "P"."PRODUCT_NAME" "PRODUCT_NAME" FROM "OE"."ORDER_ITEMS" "O","OE"."PRODUCT_INFORMATION" "P" WHERE "O"."UNIT_PRICE"=15 AND "O"."QUANTITY">1 AND "P"."PRODUCT_ID"="O"."PRODUCT_ID" Objects referenced in the statement PRODUCT_INFORMATION[P] 92194, type = 1 ORDER_ITEMS[O] 92197, type = 1 Objects in the hash table Hash table Object 92197, type = 1, ownerid = 6573730143572393221: No Dynamic Sampling Directives for the object Hash table Object 92194, type = 1, ownerid = 17822962561575639002: No Dynamic Sampling Directives for the object Return code in qosdInitDirCtx: ENBLD =================================== SPD: END context at statement level =================================== ======================================= SPD: BEGIN context at query block level ======================================= Query Block SEL$1 (#0) Return code in qosdSetupDirCtx4QB: NOCTX ===================================== SPD: END context at query block level ===================================== SPD: Return code in qosdDSDirSetup: NOCTX, estType = TABLE SPD: Generating finding id: type = 1, reason = 1, objcnt = 1, obItr = 0, objid = 92197, objtyp = 1, vecsize = 6, colvec = [4, 5, ], fid = 2896834833840853267 SPD: Inserted felem, fid=2896834833840853267, ftype = 1, freason = 1, dtype = 0, dstate = 0, dflag = 0, ver = YES, keep = YES SPD: qosdCreateFindingSingTab retCode = CREATED, fid = 2896834833840853267 SPD: qosdCreateDirCmp retCode = CREATED, fid = 2896834833840853267 SPD: Return code in qosdDSDirSetup: NOCTX, estType = TABLE SPD: Return code in qosdDSDirSetup: NOCTX, estType = INDEX_SCAN SPD: Return code in qosdDSDirSetup: NOCTX, estType = INDEX_FILTER SPD: Return code in qosdDSDirSetup: NOCTX, estType = INDEX_SCAN SPD: Return code in qosdDSDirSetup: NOCTX, estType = INDEX_FILTER SPD: Return code in qosdDSDirSetup: NOCTX, estType = JOIN SPD: Return code in qosdDSDirSetup: NOCTX, estType = INDEX_FILTER SPD: Return code in qosdDSDirSetup: NOCTX, estType = INDEX_SCAN SPD: Return code in qosdDSDirSetup: NOCTX, estType = INDEX_FILTER SPD: Return code in qosdDSDirSetup: NOCTX, estType = INDEX_SKIP_SCAN SPD: Return code in qosdDSDirSetup: NOCTX, estType = INDEX_FILTER SPD: Return code in qosdDSDirSetup: NOCTX, estType = JOIN SPD: Return code in qosdDSDirSetup: NOCTX, estType = INDEX_FILTER SPD: Return code in qosdDSDirSetup: NOCTX, estType = INDEX_SCAN SPD: Return code in qosdDSDirSetup: NOCTX, estType = INDEX_FILTER SPD: Return code in qosdDSDirSetup: NOCTX, estType = INDEX_SCAN SPD: Return code in qosdDSDirSetup: NOCTX, estType = INDEX_FILTER SPD: Return code in qosdDSDirSetup: NOCTX, estType = INDEX_SCAN SPD: Return code in qosdDSDirSetup: NOCTX, estType = INDEX_FILTER SPD: Return code in qosdDSDirSetup: NOCTX, estType = INDEX_SCAN SPD: Return code in qosdDSDirSetup: NOCTX, estType = INDEX_FILTER SPD: Return code in qosdDSDirSetup: NOCTX, estType = INDEX_SCAN SPD: Return code in qosdDSDirSetup: NOCTX, estType = INDEX_FILTER SPD: Return code in qosdDSDirSetup: NOCTX, estType = INDEX_SCAN SPD: Return code in qosdDSDirSetup: NOCTX, estType = INDEX_FILTER SPD: Return code in qosdDSDirSetup: NOCTX, estType = INDEX_SCAN SPD: Return code in qosdDSDirSetup: NOCTX, estType = INDEX_FILTER SPD: Return code in qosdDSDirSetup: NOCTX, estType = INDEX_SCAN SPD: Return code in qosdDSDirSetup: NOCTX, estType = INDEX_FILTER SPD: Return code in qosdDSDirSetup: NOCTX, estType = INDEX_SCAN SPD: Return code in qosdDSDirSetup: NOCTX, estType = INDEX_FILTER SPD: Return code in qosdDSDirSetup: NOCTX, estType = INDEX_SCAN SPD: Return code in qosdDSDirSetup: NOCTX, estType = INDEX_FILTER SPD: Return code in qosdDSDirSetup: NOCTX, estType = INDEX_SCAN SPD: Return code in qosdDSDirSetup: NOCTX, estType = INDEX_FILTER SPD: Return code in qosdDSDirSetup: NOCTX, estType = INDEX_SCAN SPD: Return code in qosdDSDirSetup: NOCTX, estType = INDEX_FILTER SPD: Return code in qosdDSDirSetup: NOCTX, estType = INDEX_SCAN SPD: Return code in qosdDSDirSetup: NOCTX, estType = INDEX_FILTER SPD: Return code in qosdDSDirSetup: NOCTX, estType = INDEX_SCAN SPD: Return code in qosdDSDirSetup: NOCTX, estType = INDEX_FILTER SPD: Generating finding id: type = 1, reason = 1, objcnt = 1, obItr = 0, objid = 92197, objtyp = 1, vecsize = 6, colvec = [4, 5, ], fid = 2896834833840853267 SPD: Modified felem, fid=2896834833840853267, ftype = 1, freason = 1, dtype = 0, dstate = 0, dflag = 0, ver = YES, keep = YES SPD: Generating finding id: type = 1, reason = 1, objcnt = 1, obItr = 0, objid = 92194, objtyp = 1, vecsize = 2, colvec = [1, ], fid = 5618517328604016300 SPD: Modified felem, fid=5618517328604016300, ftype = 1, freason = 1, dtype = 0, dstate = 0, dflag = 0, ver = NO, keep = NO SPD: Generating finding id: type = 1, reason = 1, objcnt = 1, obItr = 0, objid = 92194, objtyp = 1, vecsize = 2, colvec = [1, ], fid = 1142802697078608149 SPD: Modified felem, fid=1142802697078608149, ftype = 1, freason = 1, dtype = 0, dstate = 0, dflag = 0, ver = NO, keep = NO SPD: Generating finding id: type = 1, reason = 2, objcnt = 2, obItr = 0, objid = 92194, objtyp = 1, vecsize = 0, obItr = 1, objid = 92197, objtyp = 1, vecsize = 0, fid = 1437680122701058051 SPD: Modified felem, fid=1437680122701058051, ftype = 1, freason = 2, dtype = 0, dstate = 0, dflag = 0, ver = NO, keep = NO select * from table(dbms_xplan.display_cursor(format=>'report')) ; ????report????adaptive plan Adaptive plan: ------------- This cursor has an adaptive plan, but adaptive plans are enabled for reporting mode only.  The plan that would be executed if adaptive plans were enabled is displayed below. ------------------------------------------------------------------------------------------ | Id  | Operation          | Name                | Rows  | Bytes | Cost (%CPU)| Time     | ------------------------------------------------------------------------------------------ |   0 | SELECT STATEMENT   |                     |       |       |     7 (100)|          | |*  1 |  HASH JOIN         |                     |     4 |   128 |     7   (0)| 00:00:01 | |*  2 |   TABLE ACCESS FULL| ORDER_ITEMS         |     4 |    48 |     3   (0)| 00:00:01 | |   3 |   TABLE ACCESS FULL| PRODUCT_INFORMATION |     1 |    20 |     1   (0)| 00:00:01 | ------------------------------------------------------------------------------------------ SQL> select SQL_ID,IS_RESOLVED_DYNAMIC_PLAN,sql_text from v$SQL WHERE SQL_TEXT like '%MALCEAN%' and sql_text not like '%like%'; SQL_ID IS -------------------------- -- SQL_TEXT -------------------------------------------------------------------------------- 6ydj1bn1bng17 Y select /*MALCEAN*/ product_name from oe.order_items o, oe.product_information p where o.unit_price=15 and quantity>1 and p.product_id=o.product_id ???? explain plan for ????default plan, ??????optimizer???final plan,??V$SQL.IS_RESOLVED_DYNAMIC_PLAN???Y,????????????? DBA_SQL_PLAN_DIRECTIVES?????????????SQL PLAN DIRECTIVES, ???12c? ???MMON?????DML ???column usage??????????,????SMON??? MMON????SGA??PLAN DIRECTIVES??? ?????DBMS_SPD.flush_sql_plan_directive???? select directive_id,type,reason from DBA_SQL_PLAN_DIRECTIVES / DIRECTIVE_ID TYPE REASON ----------------------------------- -------------------------------- ----------------------------- 10321283028317893030 DYNAMIC_SAMPLING JOIN CARDINALITY MISESTIMATE 4757086536465754886 DYNAMIC_SAMPLING JOIN CARDINALITY MISESTIMATE 16085268038103121260 DYNAMIC_SAMPLING JOIN CARDINALITY MISESTIMATE SQL> set pages 9999 SQL> set lines 300 SQL> col state format a5 SQL> col subobject_name format a11 SQL> col col_name format a11 SQL> col object_name format a13 SQL> select d.directive_id, o.object_type, o.object_name, o.subobject_name col_name, d.type, d.state, d.reason 2 from dba_sql_plan_directives d, dba_sql_plan_dir_objects o 3 where d.DIRECTIVE_ID=o.DIRECTIVE_ID 4 and o.object_name in ('ORDER_ITEMS') 5 order by d.directive_id; DIRECTIVE_ID OBJECT_TYPE OBJECT_NAME COL_NAME TYPE STATE REASON ------------ ------------ ------------- ----------- -------------------------------- ----- ------------------------------------- --- 1.8156E+19 COLUMN ORDER_ITEMS UNIT_PRICE DYNAMIC_SAMPLING NEW SINGLE TABLE CARDINALITY MISESTIMATE 1.8156E+19 TABLE ORDER_ITEMS DYNAMIC_SAMPLING NEW SINGLE TABLE CARDINALITY MISESTIMATE 1.8156E+19 COLUMN ORDER_ITEMS QUANTITY DYNAMIC_SAMPLING NEW SINGLE TABLE CARDINALITY MISESTIMATE DBA_SQL_PLAN_DIRECTIVES????? _BASE_OPT_DIRECTIVE ? _BASE_OPT_FINDING SELECT d.dir_own#, d.dir_id, d.f_id, decode(type, 1, 'DYNAMIC_SAMPLING', 'UNKNOWN'), decode(state, 1, 'NEW', 2, 'MISSING_STATS', 3, 'HAS_STATS', 4, 'CANDIDATE', 5, 'PERMANENT', 6, 'DISABLED', 'UNKNOWN'), decode(bitand(flags, 1), 1, 'YES', 'NO'), cast(d.created as timestamp), cast(d.last_modified as timestamp), -- Please see QOSD_DAYS_TO_UPDATE and QOSD_PLUS_SECONDS for more details -- about 6.5 cast(d.last_used as timestamp) - NUMTODSINTERVAL(6.5, 'day') FROM sys.opt_directive$ d ??dbms_spd??? SQL PLAN DIRECTIVES, SQL PLAN DIRECTIVES???retention ???53?: Package: DBMS_SPD This package provides subprograms for managing Sql Plan Directives(SPD). SPD are objects generated automatically by Oracle server. For example, if server detects that the single table cardinality estimated by optimizer is off from the actual number of rows returned when accessing the table, it will automatically create a directive to do dynamic sampling for the table. When any Sql statement referencing the table is compiled, optimizer will perform dynamic sampling for the table to get more accurate estimate. Notes: DBMSL_SPD is a invoker-rights package. The invoker requires ADMINISTER SQL MANAGEMENT OBJECT privilege for executing most of the subprograms of this package. Also the subprograms commit the current transaction (if any), perform the operation and commit it again. DBA view dba_sql_plan_directives shows all the directives created in the system and the view dba_sql_plan_dir_objects displays the objects that are included in the directives. -- Default value for SPD_RETENTION_WEEKS SPD_RETENTION_WEEKS_DEFAULT CONSTANT varchar2(4) := '53'; | STATE : NEW : Newly created directive. | : MISSING_STATS : The directive objects do not | have relevant stats. | : HAS_STATS : The objects have stats. | : PERMANENT : A permanent directive. Server | evaluated effectiveness and these | directives are useful. | | AUTO_DROP : YES : Directive will be dropped | automatically if not | used for SPD_RETENTION_WEEKS. | This is the default behavior. | NO : Directive will not be dropped | automatically. Procedure: flush_sql_plan_directive This procedure allows manually flushing the Sql Plan directives that are automatically recorded in SGA memory while executing sql statements. The information recorded in SGA are periodically flushed by oracle background processes. This procedure just provides a way to flush the information manually. ????”_optimizer_dynamic_plans”(enable dynamic plans)????????,???TRUE??DYNAMIC PLAN? ???FALSE???????????? ????,Dynamic Plan????????????Nested Loop?Hash Join???case ,????????Nested loop???????????HASH JOIN,?HASH JOIN????????????????? ????????subplan?????,???? pass?? ?join method???,?????STATISTICS COLLECTOR???cardinality?,???????HASH JOIN?????Nested Loop,????????????subplan?????access path; ???????Sales??????????????????,????HASH JOIN,??SUBPLAN??customers?????????;?????Nested Loop,???????cust_id?????Range Scan+Access by Rowid? Cardinality feedback Cardinality feedback????????11.2????,????????re-optimization???;  ???????????,Cardinality feedback?????????????????????????? ???????????????????,?????????????????,??????????Cardinality feedback????????????? ????????????????????????? ??????????????Cardinality feedback ??: ????????,???????????,??????????,????????????????selectivity ??? ????????????: ??????,?????????????????????????????????,??????????????????? ????????????????????????????????????????,?????????????????????????? ?????????,???????????????,?????????? ??????????Cardinality ????,??????join Cardinality ????????? Cardinality feedback???????cursor?,?Cursor???aged out????? SELECT /*+ gather_plan_statistics */ product_name FROM order_items o, product_information p WHERE o.unit_price = 15 AND quantity > 1 AND p.product_id = o.product_id Plan hash value: 1553478007 ---------------------------------------------------------------------------------------------------------------------------------------- | Id | Operation | Name | Starts | E-Rows | A-Rows | A-Time | Buffers | Reads | OMem | 1Mem | Used-Mem | ---------------------------------------------------------------------------------------------------------------------------------------- | 0 | SELECT STATEMENT | | 1 | | 13 |00:00:00.01 | 24 | 20 | | | | |* 1 | HASH JOIN | | 1 | 4 | 13 |00:00:00.01 | 24 | 20 | 2061K| 2061K| 429K (0)| |* 2 | TABLE ACCESS FULL| ORDER_ITEMS | 1 | 4 | 13 |00:00:00.01 | 7 | 6 | | | | | 3 | TABLE ACCESS FULL| PRODUCT_INFORMATION | 1 | 1 | 288 |00:00:00.01 | 17 | 14 | | | | ---------------------------------------------------------------------------------------------------------------------------------------- SELECT /*+ gather_plan_statistics */ product_name FROM order_items o, product_information p WHERE o.unit_price = 15 AND quantity > 1 AND p.product_id = o.product_id Plan hash value: 1553478007 ------------------------------------------------------------------------------------------------------------------------------- | Id | Operation | Name | Starts | E-Rows | A-Rows | A-Time | Buffers | OMem | 1Mem | Used-Mem | ------------------------------------------------------------------------------------------------------------------------------- | 0 | SELECT STATEMENT | | 1 | | 13 |00:00:00.01 | 24 | | | | |* 1 | HASH JOIN | | 1 | 13 | 13 |00:00:00.01 | 24 | 2061K| 2061K| 413K (0)| |* 2 | TABLE ACCESS FULL| ORDER_ITEMS | 1 | 13 | 13 |00:00:00.01 | 7 | | | | | 3 | TABLE ACCESS FULL| PRODUCT_INFORMATION | 1 | 288 | 288 |00:00:00.01 | 17 | | | | ------------------------------------------------------------------------------------------------------------------------------- Note ----- - statistics feedback used for this statement SQL> select count(*) from v$SQL where SQL_ID='cz0hg2zkvd10y'; COUNT(*) ---------- 2 SQL>select sql_ID,USE_FEEDBACK_STATS FROM V$SQL_SHARED_CURSOR where USE_FEEDBACK_STATS ='Y'; SQL_ID U ------------- - cz0hg2zkvd10y Y ????????Cardinality feedback????,???????????????????????????,????????????order_items???????? ????2??????plan hash value??(??????????),?????2????child cursor??????gather_plan_statistics???actual : A-ROWS  estimate :E-ROWS????????? Automatic Re-optimization ???dynamic plan, Re-optimization???????????????  ?  ??????????????? ????????????????????????????????  ???????????,??????????????, ???????????????????? ???????????  Re-optimization??, ????????????????????? Re-optimization????dynamic plan??????????  dynamic plan????????????????????, ???????????????????? ????,??????????join order ??????????????,?????????????join order????? ??????,????????Re-optimization, ??Re-optimization ??????????????????? ?Oracle database 12c?,join statistics?????????????????????,??????????????????????Re-optimization???????????adaptive cursor sharing????? ????????????????,???????????? ????? ???????statistics collectors ????????????????????Re-optimization??????2?????????????,???????????????? ??????????????Re-optimization?????,?????????????????????? ???v$SQL??????IS_REOPTIMIZABLE?????????????????????Re-optimization,??????????Re-optimization???,?????Re-optimization ,???????reporting????? IS_REOPTIMIZABLE VARCHAR2(1) This columns shows whether the next execution matching this child cursor will trigger a reoptimization. The values are:   Y: If the next execution will trigger a reoptimization R: If the child cursor contains reoptimization information, but will not trigger reoptimization because the cursor was compiled in reporting mode N: If the child cursor has no reoptimization information ??1: select plan_table_output from table (dbms_xplan.display_cursor('gwf99gfnm0t7g',NULL,'ALLSTATS LAST')); SQL_ID  gwf99gfnm0t7g, child number 0 ------------------------------------- SELECT /*+ SFTEST gather_plan_statistics */ o.order_id, v.product_name FROM  orders o,   ( SELECT order_id, product_name FROM order_items o, product_information p     WHERE  p.product_id = o.product_id AND list_price < 50 AND min_price < 40  ) v WHERE o.order_id = v.order_id Plan hash value: 1906736282 ------------------------------------------------------------------------------------------------------------------------------------------- | Id  | Operation             | Name                | Starts | E-Rows | A-Rows |   A-Time   | Buffers | Reads  |  OMem |  1Mem | Used-Mem | ------------------------------------------------------------------------------------------------------------------------------------------- |   0 | SELECT STATEMENT      |                     |      1 |        |    269 |00:00:00.02 |    1336 |     18 |       |       |          | |   1 |  NESTED LOOPS         |                     |      1 |      1 |    269 |00:00:00.02 |    1336 |     18 |       |       |          | |   2 |   MERGE JOIN CARTESIAN|                     |      1 |      4 |   9135 |00:00:00.02 |      34 |     15 |       |       |          | |*  3 |    TABLE ACCESS FULL  | PRODUCT_INFORMATION |      1 |      1 |     87 |00:00:00.01 |      33 |     14 |       |       |          | |   4 |    BUFFER SORT        |                     |     87 |    105 |   9135 |00:00:00.01 |       1 |      1 |  4096 |  4096 | 4096  (0)| |   5 |     INDEX FULL SCAN   | ORDER_PK            |      1 |    105 |    105 |00:00:00.01 |       1 |      1 |       |       |          | |*  6 |   INDEX UNIQUE SCAN   | ORDER_ITEMS_UK      |   9135 |      1 |    269 |00:00:00.01 |    1302 |      3 |       |       |          | ------------------------------------------------------------------------------------------------------------------------------------------- Predicate Information (identified by operation id): ---------------------------------------------------    3 - filter(("MIN_PRICE"<40 AND "LIST_PRICE"<50))    6 - access("O"."ORDER_ID"="ORDER_ID" AND "P"."PRODUCT_ID"="O"."PRODUCT_ID") SQL_ID  gwf99gfnm0t7g, child number 1 ------------------------------------- SELECT /*+ SFTEST gather_plan_statistics */ o.order_id, v.product_name FROM  orders o,   ( SELECT order_id, product_name FROM order_items o, product_information p     WHERE  p.product_id = o.product_id AND list_price < 50 AND min_price < 40  ) v WHERE o.order_id = v.order_id Plan hash value: 35479787 -------------------------------------------------------------------------------------------------------------------------------------------- | Id  | Operation              | Name                | Starts | E-Rows | A-Rows |   A-Time   | Buffers | Reads  |  OMem |  1Mem | Used-Mem | -------------------------------------------------------------------------------------------------------------------------------------------- |   0 | SELECT STATEMENT       |                     |      1 |        |    269 |00:00:00.01 |      63 |      3 |       |       |          | |   1 |  NESTED LOOPS          |                     |      1 |    269 |    269 |00:00:00.01 |      63 |      3 |       |       |          | |*  2 |   HASH JOIN            |                     |      1 |    313 |    269 |00:00:00.01 |      42 |      3 |  1321K|  1321K| 1234K (0)| |*  3 |    TABLE ACCESS FULL   | PRODUCT_INFORMATION |      1 |     87 |     87 |00:00:00.01 |      16 |      0 |       |       |          | |   4 |    INDEX FAST FULL SCAN| ORDER_ITEMS_UK      |      1 |    665 |    665 |00:00:00.01 |      26 |      3 |       |       |          | |*  5 |   INDEX UNIQUE SCAN    | ORDER_PK            |    269 |      1 |    269 |00:00:00.01 |      21 |      0 |       |       |          | -------------------------------------------------------------------------------------------------------------------------------------------- Predicate Information (identified by operation id): ---------------------------------------------------    2 - access("P"."PRODUCT_ID"="O"."PRODUCT_ID")    3 - filter(("MIN_PRICE"<40 AND "LIST_PRICE"<50))    5 - access("O"."ORDER_ID"="ORDER_ID") Note -----    - statistics feedback used for this statement    SQL> select IS_REOPTIMIZABLE,child_number FROM V$SQL  A where A.SQL_ID='gwf99gfnm0t7g'; IS CHILD_NUMBER -- ------------ Y             0 N             1    1* select child_number,other_xml From v$SQL_PLAN  where SQL_ID='gwf99gfnm0t7g' and other_xml is not nul SQL> / CHILD_NUMBER OTHER_XML ------------ --------------------------------------------------------------------------------            1 <other_xml><info type="cardinality_feedback">yes</info><info type="db_version">1              2.1.0.1</info><info type="parse_schema"><![CDATA["OE"]]></info><info type="plan_              hash">35479787</info><info type="plan_hash_2">3382491761</info><outline_data><hi              nt><![CDATA[IGNORE_OPTIM_EMBEDDED_HINTS]]></hint><hint><![CDATA[OPTIMIZER_FEATUR              ES_ENABLE('12.1.0.1')]]></hint><hint><![CDATA[DB_VERSION('12.1.0.1')]]></hint><h              int><![CDATA[ALL_ROWS]]></hint><hint><![CDATA[OUTLINE_LEAF(@"SEL$F5BB74E1")]]></              hint><hint><![CDATA[MERGE(@"SEL$2")]]></hint><hint><![CDATA[OUTLINE(@"SEL$1")]]>              </hint><hint><![CDATA[OUTLINE(@"SEL$2")]]></hint><hint><![CDATA[FULL(@"SEL$F5BB7              4E1" "P"@"SEL$2")]]></hint><hint><![CDATA[INDEX_FFS(@"SEL$F5BB74E1" "O"@"SEL$2"              ("ORDER_ITEMS"."ORDER_ID" "ORDER_ITEMS"."PRODUCT_ID"))]]></hint><hint><![CDATA[I              NDEX(@"SEL$F5BB74E1" "O"@"SEL$1" ("ORDERS"."ORDER_ID"))]]></hint><hint><![CDATA[              LEADING(@"SEL$F5BB74E1" "P"@"SEL$2" "O"@"SEL$2" "O"@"SEL$1")]]></hint><hint><![C              DATA[USE_HASH(@"SEL$F5BB74E1" "O"@"SEL$2")]]></hint><hint><![CDATA[USE_NL(@"SEL$              F5BB74E1" "O"@"SEL$1")]]></hint></outline_data></other_xml>            0 <other_xml><info type="db_version">12.1.0.1</info><info type="parse_schema"><![C              DATA["OE"]]></info><info type="plan_hash">1906736282</info><info type="plan_hash              _2">2579473118</info><outline_data><hint><![CDATA[IGNORE_OPTIM_EMBEDDED_HINTS]]>              </hint><hint><![CDATA[OPTIMIZER_FEATURES_ENABLE('12.1.0.1')]]></hint><hint><![CD              ATA[DB_VERSION('12.1.0.1')]]></hint><hint><![CDATA[ALL_ROWS]]></hint><hint><![CD              ATA[OUTLINE_LEAF(@"SEL$F5BB74E1")]]></hint><hint><![CDATA[MERGE(@"SEL$2")]]></hi              nt><hint><![CDATA[OUTLINE(@"SEL$1")]]></hint><hint><![CDATA[OUTLINE(@"SEL$2")]]>              </hint><hint><![CDATA[FULL(@"SEL$F5BB74E1" "P"@"SEL$2")]]></hint><hint><![CDATA[              INDEX(@"SEL$F5BB74E1" "O"@"SEL$1" ("ORDERS"."ORDER_ID"))]]></hint><hint><![CDATA              [INDEX(@"SEL$F5BB74E1" "O"@"SEL$2" ("ORDER_ITEMS"."ORDER_ID" "ORDER_ITEMS"."PROD              UCT_ID"))]]></hint><hint><![CDATA[LEADING(@"SEL$F5BB74E1" "P"@"SEL$2" "O"@"SEL$1              " "O"@"SEL$2")]]></hint><hint><![CDATA[USE_MERGE_CARTESIAN(@"SEL$F5BB74E1" "O"@"              SEL$1")]]></hint><hint><![CDATA[USE_NL(@"SEL$F5BB74E1" "O"@"SEL$2")]]></hint></o              utline_data></other_xml> ??2: SELECT /*+gather_plan_statistics*/ * FROM customers WHERE cust_state_province='CA' AND country_id='US'; SELECT * FROM TABLE(DBMS_XPLAN.DISPLAY_CURSOR(FORMAT=>'ALLSTATS LAST')); PLAN_TABLE_OUTPUT ------------------------------------- SQL_ID b74nw722wjvy3, child number 0 ------------------------------------- select /*+gather_plan_statistics*/ * from customers where CUST_STATE_PROVINCE='CA' and country_id='US' Plan hash value: 1683234692 -------------------------------------------------------------------------------------------------- | Id | Operation | Name | Starts | E-Rows | A-Rows | A-Time | Buffers | Reads | -------------------------------------------------------------------------------------------------- | 0 | SELECT STATEMENT | | 1 | | 29 |00:00:00.01 | 17 | 14 | |* 1 | TABLE ACCESS FULL| CUSTOMERS | 1 | 8 | 29 |00:00:00.01 | 17 | 14 | -------------------------------------------------------------------------------------------------- Predicate Information (identified by operation id): --------------------------------------------------- 1 - filter(("CUST_STATE_PROVINCE"='CA' AND "COUNTRY_ID"='US')) SELECT SQL_ID, CHILD_NUMBER, SQL_TEXT, IS_REOPTIMIZABLE FROM V$SQL WHERE SQL_TEXT LIKE 'SELECT /*+gather_plan_statistics*/%'; SQL_ID CHILD_NUMBER SQL_TEXT I ------------- ------------ ----------- - b74nw722wjvy3 0 select /*+g Y ather_plan_ statistics* / * from cu stomers whe re CUST_STA TE_PROVINCE ='CA' and c ountry_id=' US' EXEC DBMS_SPD.FLUSH_SQL_PLAN_DIRECTIVE; SELECT TO_CHAR(d.DIRECTIVE_ID) dir_id, o.OWNER, o.OBJECT_NAME, o.SUBOBJECT_NAME col_name, o.OBJECT_TYPE, d.TYPE, d.STATE, d.REASON FROM DBA_SQL_PLAN_DIRECTIVES d, DBA_SQL_PLAN_DIR_OBJECTS o WHERE d.DIRECTIVE_ID=o.DIRECTIVE_ID AND o.OWNER IN ('SH') ORDER BY 1,2,3,4,5; DIR_ID OWNER OBJECT_NAME COL_NAME OBJECT TYPE STATE REASON ----------------------- ----- ------------- ----------- ------ ---------------- ----- ------------------------ 1484026771529551585 SH CUSTOMERS COUNTRY_ID COLUMN DYNAMIC_SAMPLING NEW SINGLE TABLE CARDINALITY MISESTIMATE 1484026771529551585 SH CUSTOMERS CUST_STATE_ COLUMN DYNAMIC_SAMPLING NEW SINGLE TABLE CARDINALITY PROVINCE MISESTIMATE 1484026771529551585 SH CUSTOMERS TABLE DYNAMIC_SAMPLING NEW SINGLE TABLE CARDINALITY MISESTIMATE SELECT /*+gather_plan_statistics*/ * FROM customers WHERE cust_state_province='CA' AND country_id='US'; ELECT * FROM TABLE(DBMS_XPLAN.DISPLAY_CURSOR(FORMAT=>'ALLSTATS LAST')); PLAN_TABLE_OUTPUT ------------------------------------- SQL_ID b74nw722wjvy3, child number 1 ------------------------------------- select /*+gather_plan_statistics*/ * from customers where CUST_STATE_PROVINCE='CA' and country_id='US' Plan hash value: 1683234692 ----------------------------------------------------------------------------------------- | Id | Operation | Name | Starts | E-Rows | A-Rows | A-Time | Buffers | ----------------------------------------------------------------------------------------- | 0 | SELECT STATEMENT | | 1 | | 29 |00:00:00.01 | 17 | |* 1 | TABLE ACCESS FULL| CUSTOMERS | 1 | 29 | 29 |00:00:00.01 | 17 | ----------------------------------------------------------------------------------------- Predicate Information (identified by operation id): --------------------------------------------------- 1 - filter(("CUST_STATE_PROVINCE"='CA' AND "COUNTRY_ID"='US')) Note ----- - cardinality feedback used for this statement SELECT SQL_ID, CHILD_NUMBER, SQL_TEXT, IS_REOPTIMIZABLE FROM V$SQL WHERE SQL_TEXT LIKE 'SELECT /*+gather_plan_statistics*/%'; SQL_ID CHILD_NUMBER SQL_TEXT I ------------- ------------ ----------- - b74nw722wjvy3 0 select /*+g Y ather_plan_ statistics* / * from cu stomers whe re CUST_STA TE_PROVINCE ='CA' and c ountry_id=' US' b74nw722wjvy3 1 select /*+g N ather_plan_ statistics* / * from cu stomers whe re CUST_STA TE_PROVINCE ='CA' and c ountry_id=' US' SELECT /*+gather_plan_statistics*/ CUST_EMAIL FROM CUSTOMERS WHERE CUST_STATE_PROVINCE='MA' AND COUNTRY_ID='US'; SELECT * FROM TABLE(DBMS_XPLAN.DISPLAY_CURSOR(FORMAT=>'ALLSTATS LAST')); PLAN_TABLE_OUTPUT ------------------------------------- SQL_ID 3tk6hj3nkcs2u, child number 0 ------------------------------------- Select /*+gather_plan_statistics*/ cust_email From customers Where cust_state_province='MA' And country_id='US' Plan hash value: 1683234692 ------------------------------------------------------------------------------- |Id | Operation | Name | Starts|E-Rows|A-Rows| A-Time |Buffers| ------------------------------------------------------------------------------- | 0 | SELECT STATEMENT | | 1 | | 2 |00:00:00.01| 16 | |*1 | TABLE ACCESS FULL| CUSTOMERS | 1 | 2| 2 |00:00:00.01| 16 | ----------------------------------------------------------------------------- Predicate Information (identified by operation id): --------------------------------------------------- 1 - filter(("CUST_STATE_PROVINCE"='MA' AND "COUNTRY_ID"='US')) Note ----- - dynamic sampling used for this statement (level=2) - 1 Sql Plan Directive used for this statement EXEC DBMS_SPD.FLUSH_SQL_PLAN_DIRECTIVE; SELECT TO_CHAR(d.DIRECTIVE_ID) dir_id, o.OWNER, o.OBJECT_NAME, o.SUBOBJECT_NAME col_name, o.OBJECT_TYPE, d.TYPE, d.STATE, d.REASON FROM DBA_SQL_PLAN_DIRECTIVES d, DBA_SQL_PLAN_DIR_OBJECTS o WHERE d.DIRECTIVE_ID=o.DIRECTIVE_ID AND o.OWNER IN ('SH') ORDER BY 1,2,3,4,5; DIR_ID OW OBJECT_NA COL_NAME OBJECT TYPE STATE REASON ------------------- -- --------- ---------- ------- --------------- ------------- ------------------------ 1484026771529551585 SH CUSTOMERS COUNTRY_ID COLUMN DYNAMIC_SAMPLING MISSING_STATS SINGLE TABLE CARDINALITY MISESTIMATE 1484026771529551585 SH CUSTOMERS CUST_STATE_ COLUMN DYNAMIC_SAMPLING MISSING_STATS SINGLE TABLE CARDINALITY PROVINCE MISESTIMATE 1484026771529551585 SH CUSTOMERS TABLE DYNAMIC_SAMPLING MISSING_STATS SINGLE TABLE CARDINALITY MISESTIMATE

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    Database ?? Database ??????? Database ?????????? Java WebLogic Server/????????·???? SOA/BPM/????? ???????/???? ID??/?????? ?????EPM/BI EPM/BI ??????? EPM/BI ???? OS/??? ???? ????? MySQL Database ?? ???? ?? ????????? ??? ?? ORACLE MASTER??Master??ORACLE MASTER Bronze?Bronze DBA11g? ??(WMV)??(MP4)2011/6/22 ORACLE MASTER??Master??ORACLE MASTER Bronze?11g SQL??????(WMV)??(MP4)2011/3/9 ORACLE MASTER??Master??ORACLE MASTER Silver?Silver DBA11g???(WMV)??(MP4)2010/3/2 ORACLE MASTER??Master??ORACLE MASTER Silver?Silver DBA11g?[10g-11g???] ??(WMV)??(MP4)2012/4/23 ORACLE MASTER??Master??ORACLE MASTER Gold DBA11g ??(WMV)??(MP4)2011/2/23 ORACLE MASTER??Master??ORACLE MASTER Gold ?Gold DBA11g ????[??]??(WMV)??(MP4)2012/4/23 ORACLE MASTER??Master??30?????? ORACLE MASTER??????(WMV)??(MP4)2012/9/3 Oracle Database???????????????!Oracle??????????!???(WMV)??(MP4)2010/9/8 Oracle Database???????????????????!? Oracle?? ?????(WMV)??(MP4)2011/4/13 Oracle Database???????????????????!? Oracle?? ??????????(WMV)??(MP4)2011/4/20 Oracle Database???????????????????????????!? ??????????-?????(WMV)??(MP4)2012/2/20 Oracle Database???????????????????????????!? ??????????-?????(WMV)??(MP4)2012/2/20 Oracle Database????????????60???????!?????????????·???????? ??(WMV)??(MP4)2011/5/17 Oracle Database???Step by Step?????!? Oracle Database 11g -?????????-??(WMV)??(MP4)2009/12/17 Oracle Database???Step by Step?????!? OracleDatabase11g -???????????(WMV)??(MP4)2009/12/24 Oracle Database???Step by Step?????!? Oracle Database 11g -?????????(WMV)??(MP4)2009/12/10 Oracle Database DBA?????????????????!???????????(WMV)??(MP4)2010/12/21 Oracle Database DBA?????????????????!????????·??????????(WMV)??(MP4)2010/11/16 Oracle Database DBA?????????????????!???????·????????(WMV)??(MP4)2010/12/15 Oracle Database DBA?????????????????!???????????(WMV)??(MP4)2010/7/21 Oracle Database DBA?????????????????!?Export/Import?????(WMV)??(MP4)2010/9/8 Oracle Database DBA??????????????????!??????????????(WMV)??(MP4)2011/7/20 Oracle Database DBA?????????·????????!!????????!?????????SQL????????(WMV)??(MP4)2010/11/24 Oracle Database DBA?????????·?????????SQL????????????!SQL????????(WMV)??(MP4)2012/1/23 Oracle Database DBA?????????·????????!!???????·??????~DiskI/O?????????~??(WMV)??(MP4)2011/3/9 Oracle Database DBA?????????·????????!!???????·??????~SQL???????~??(WMV)??(MP4)2011/9/20 Oracle Database DBA?????????·????????!???????·??????-Statspack??-??(WMV)??(MP4)2010/7/28 Oracle Database DBA?????????·????????!!???????·??????~??????????~??(WMV)??(MP4)2010/8/4 Oracle Database DBA?????????·????????!!???????·??????-?????????-??(WMV)??(MP4)2010/7/14 Oracle Database DBA?????????·?????? ??!????????????? ??????(WMV)??(MP4)2010/7/7 Oracle Database DBA?????????·????????!????????????? ??????(WMV)??(MP4)2010/7/7 Oracle Database DBA?????????·????????!! ????????DB ??????Tips??(WMV)??(MP4)2010/8/5 Oracle Database DBA??????????!!??????~Oracle Database???~??(WMV)??(MP4)2010/8/31 Oracle Database DBA??????????!!??????~OracleDatabase????~??(WMV)??(MP4)2010/8/24 Oracle Database DBA???????????????????????????????????????(WMV)??(MP4)2010/4/27 Oracle Database DBA????????&?????????????·???? - ?????RMAN??????(WMV)??(MP4)2010/10/13 Oracle Database DBA????????&???????!!??????·????-???????????-??(WMV)??(MP4)2010/9/8 Oracle Database DBA????????&???????!??????·???? ~?????? VS RMAN ?????????~??(WMV)??(MP4)2012/1/23 Oracle Database DBA????????&???????!??????·???? ~????????????~??(WMV)??(MP4)2011/7/27 Oracle Database DBA????????&?????????????????-???????????????????(WMV)??(MP4)2010/10/6 Oracle Database Developer??????????????? Oracle SQL????(WMV)??(MP4)2010/10/20 Oracle Database Developer??????????????? Oracle PL/SQL????(WMV)??(MP4)2012/1/23 Oracle Database Developer????????!!PL/SQL????????(WMV)??(MP4)2011/03 Oracle Database Developer?????????????????????(WMV)??(MP4)2011/5/25 Oracle Database Developer??Java??java???!??(WMV)??(MP4)2009/11/26 Database ??????? ???? ?? ????????? ??? ?? DB???????????????!Oracle Database????????(WMV)??(MP4)2010/5/12 DB???????????????????? Oracle Enterprise Manager??(WMV)??(MP4)2012/1/23 DB??????????!Oracle Enterprise Manager???????????????? ??(WMV)??(MP4)2012/1/23 DB??????????!Oracle Enterprise Manager??????????????·?????? ??(WMV)??(MP4)2012/1/23 DB?????????????(UX)????????????????????(WMV)??(MP4)2011/4/6 DB???????????????????????????????Oracle Enterprise Manager??????!??(WMV)??(MP4)2012/1/23 DB???JP1??????????????????????!JP1???????????(WMV)??(MP4)2011/6/9 DB???JP1JP1???????!DB????????·??????!??(WMV)??(MP4)2011/1/12 DB???SAP"SAP on Oracle Database"???Tips??(WMV)??(MP4)2011/1/12 DB?????????????????! 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APEX4.0??????(WMV)??(MP4)2011/2/9 DB???APEX?????!????????!Oracle APEX???????????(WMV)??(MP4)2011/6/23 DB???Large Object??·???????DB????? -LOB???????-??(WMV)??(MP4)2010/2/4 DB???XMLOracle Database???????XML???????(WMV)??(MP4)2011/3/16 DB???XML??????XML?? - ?????! XML??? -??(WMV)??(MP4)2010/8/18 DB???XML??????XML?? - Oracle????XML -??(WMV)??(MP4)2010/8/25 DB???????SQL?????!Oracle Database????????Oracle Text???????(WMV)??(MP4) - DB???Oracle Data Guard??!Oracle Data Guard ????????????????????(WMV)??(MP4)2012/1/23 DB???Oracle Real Application Clusters??!?????????? ~RAC???~??(WMV)??(MP4)2012/1/23 DB???Oracle Real Application Clusters??!?????????? ~RAC??? ~??(WMV)??(MP4)2012/1/23 DB???Oracle Real Application Clusters??!Oracle RAC????????????????????????(WMV)??(MP4)2012/1/23 DB???Oracle Real Application Clusters??????!RAC????????????(WMV)??(MP4)2012/1/23 DB???Oracle Real Application Clusters?????????????!!60?????RAC????(WMV)??(MP4)2010/12/8 DB???????????????????????????!!?Oracle Database Firewall? ??(WMV)??(MP4)2012/1/23 DB?????????Oracle Database Firewall??????????? ??(WMV)??(MP4)2012/5/14 DB?????????????????????????????????????????(WMV)??(MP4)2011/5/11 DB??????????????????????????????????????(WMV)??(MP4)2011/4/19 DB????????????????! ???????????????(WMV)??(MP4)2012/1/23 DB?????????????????????????????????(WMV)??(MP4)2010/11/16 DB???????????????????????????????????????????????(WMV)??(MP4)2011/2/9 DB???????????????~???????~??(WMV)??(MP4)2010/12/22 DB???????????????~????/????????~??(WMV)??(MP4)2011/5/24 DB??????Oracle VM 3.0 ???????(WMV)??(MP4)2011/10/3 DB??????????????BCP/BCM???Oracle??????????(WMV)??(MP4)2011/7/13 DB???????????????????????????????????????(WMV)??(MP4)2011/7/12 DB????????DB??????????!??????? Oracle ????????????? ??(WMV)??(MP4)2012/1/23 DB??????????????????!?????????????????(WMV)??(MP4)2011/6/22 DB??????????????????????(WMV)??(MP4)2011/10/17 DB???????????????????????????(WMV)??(MP4)2011/10/17 DB????????????????~?????????????????IT????~??(WMV)??(MP4)2009/12/22 DB??????????!???????? ~????????????????~??(WMV)??(MP4)2011/11/1 DB???????????????????? -???????????(WMV)??(MP4)2011/6/21 DB????????20?????? Oracle GoldenGate??(WMV)??(MP4)2012/4/23 DB????????Oracle GoldenGate?????????????(WMV)??(MP4)2012/5/14 DB???????????????????????????!Oracle GoldenGate??????(WMV)??(MP4)2011/11/1 DB???????????????????!GoldenGate????DB?????????(WMV)??(MP4)2011/8/24 DB????????????????????????? Oracle GoldenGate ????????????! ??(WMV)??(MP4)2012/1/23 DB???????? ??????????????????????????????(WMV)??(MP4)2011/03 DB???????????????!! Oracle Data Integrator??????????(WMV)??(MP4)2009/12/17 DB??????????!??????????????????????(WMV)??(MP4)2011/4/6 DB???????????????????????Oracle Database ????? ????(WMV)??(MP4)2012/1/23 DB???????????????????????Oracle Database ????? ????(WMV)??(MP4)2012/1/23 DB????????????!??????·??????????????????(WMV)??(MP4)2012/1/23 DB???Oracle Partitioning??!????????????????? ????(WMV)??(MP4)2012/1/23 DB???Oracle Partitioning??!????????????????? ????(WMV)??(MP4)2012/1/23 DB?????????????????!SQL?????????? ??(WMV)??(MP4)2010/12/21 DB???Exadata20?????? Oracle Exadata??(WMV)??(MP4)2012/4/23 DB???ExadataOracle Exadata??????????????????(WMV)??(MP4)2012/5/14 DB???Exadata????!Oracle Exadata????? ??(WMV)??(MP4)2011/10/17 DB???ExadataOracle Exadata????????????????????????? ??(WMV)??(MP4)2012/1/23 DB?????????DB?????DB????????????????? -Oracle TimesTen ????-??(WMV)??(MP4)2012/1/23 DB?????????DBWeb????????????!????????????????(WMV)??(MP4)2010/11/4 DB????????DBA?"???????" ????????????????(WMV)??(MP4)2010/8/25 DB?????????????!?Oracle ASM??????????????(WMV)??(MP4)2011/7/8 DB????????Oracle ASM ? Oracle Clusterware ??????????? ??(WMV)??(MP4)2012/1/23 DB????????????????????????????????? - Oracle ASM Cluster File System (ACFS)????! ??(WMV)??(MP4)2012/1/23 DB??????????????????/????·????????Flashback Database with SSD???(WMV)??(MP4)2011/10/17 DB???????????????????DB??????~RAC VM with SSD??(WMV)??(MP4)2011/1/11 DB????????Oracle???????????? SSD?????!??(WMV)??(MP4)2010/8/11 DB??????????????NAS??????!Oracle Database?I/O???????NFS????????????SSD?????????????(WMV)??(MP4)2012/1/23 DB????????????! ???????????? ~????·???????????????~??(WMV)??(MP4)2009/3/25 DB??????????!???????????????????(WMV)??(MP4)2011/3/15 DB???????????????????????!??????·?????????(WMV)??(MP4)2010/6/23 Windows/.Net?????????Oracle on Windows-???? OVM,Hyper-V????(WMV)??(MP4)2011/4/13 Windows/.Net????????Windows Server?Oracle?????!??(WMV)??(MP4)2010/5/19 Windows/.Net????????Oracle on Windows - ??????&???? ?????(WMV)??(MP4)2011/4/20 Windows/.Net??????.Net.NET + Oracle Database ??????????????????????(WMV)??(MP4)2012/1/23 Windows/.Net??????.Net.NET????????Oracle Database ??(WMV)??(MP4)2011/1/20 Windows/.Net??????.NetOracle on Windows-.NET+Oracle ???????(WMV)??(MP4)2011/6/28 Windows/.Net??????.NetVB6????.NET? ~DB????????????~??(WMV)??(MP4)2010/8/4 Windows/.Net??????.Net.NET+Oracle ???????????????????(WMV)??(MP4)2011/10/3 Windows/.Net??????Active Directory30????!Active Directory+Oracle??(WMV)??(MP4)2010/9/8 Windows/.Net??????AccessAccess????WEB?????????????????????????(WMV)??(MP4)2011/7/20 Windows/.Net??????Oracle Real Application ClustersWindows?RAC??!????????????(WMV)??(MP4)2010/9/1 Windows/.Net????????????Oracle on Windows ~???????~ ??(WMV)??(MP4)2011/1/18 Windows/.Net????????????Oracle on Windows ~???????~ ??(WMV)??(MP4)2011/1/20 Windows/.Net???????????MSCS????!?Windows+Oracle????????(WMV)??(MP4)2010/8/4 ???????11gR2???????!Oracle DB 11g???????/??????(WMV)??(MP4)2011/4/14 ???????11gR2???! Oracle Database 11g R2 ?????????(WMV)??(MP4)2010/11/17 ???????11gR2DB??????·??????????11g R2?????(WMV)??(MP4)2010/9/15 ????????????????DWH????????????????·??????????(WMV)??(MP4)2010/11/25 ????????????????DWH????????????????·??????????(WMV)??(MP4)2010/11/25 ????????????????DWH????????????????·??????????(WMV)??(MP4)2010/11/25 Database ?????????? ???? ?? ????????? ??? ?? Oracle Master Platinum??Oracle Real Application Clusters?Platinum???????Platinum???!?????? Oracle RAC ?????????(WMV)??(MP4)2010/1/26 Oracle Master Platinum??????????Platinum??????? Platinum???!???????Oracle??????????????(WMV)??(MP4)2010/4/21 Oracle Master Platinum????????Platinum??:?????????????????????(WMV)??(MP4)2010/5/26 Oracle Master Platinum????????·?????Platinum??????? Platinum???! ????????????·?????????(WMV)??(MP4)2010/3/9 ????????????????????????????!?????????&?????????(WMV)??(MP4)2012/1/23 ????????????????????????????!SQL????????? ??? Part1&2??(WMV)??(MP4)2010/10/12 ????????????????????????????!SQL????????? ??? Part3 ??(WMV)??(MP4)2010/10/19 ????????????????????????????!SQL????????? ??? Part4 ??(WMV)??(MP4)2011/1/27 ????????????????????????????!SQL????????? ??? Part5 ??(WMV)??(MP4)2011/1/27 ????????????????????????????!?????????????????????(WMV)??(MP4)2012/1/23 ????????????????????????????!????????? Part1 ??(WMV)??(MP4) - ????????????????????????????!????????? Part2 ??(WMV)??(MP4)2011/7/26 ????????????????????????????!????????? Part3 ??(WMV)??(MP4)2010/4/28 ????????????????????????????!??????? Part1 ??(WMV)??(MP4)2011/11/1 ????????????????????????????????????????? Part2 ??(WMV)??(MP4)2012/5/28 ????????????????????????????!???????????????????????????? ??(WMV)??(MP4)2012/1/23 ??????????????????????????!??????? Part1 ??(WMV)??(MP4)2011/2/10 ??????????????????????????!??????? Part2 ??(WMV)??(MP4)2011/3/23 ??????????????????????????!??????? Part3 ??(WMV)??(MP4)2011/4/26 ??????????????????????????!??????? Part4 ??(WMV)??(MP4)2011/5/26 ???????????Exadata???????????!Exadata???????????????????Tips??(WMV)??(MP4)2012/1/23 ?????????????????DB???????????!??TimesTen?????????? ??(WMV)??(MP4)2012/1/23 ???????????????????????????!GoldenGate?????????????????????(WMV)??(MP4)2012/1/23 ???????????EDA/CEP???????????!Oracle CEP?????????·?????????????(WMV)??(MP4)2012/1/23 ????????????????????????????????!???????????????????(WMV)??(MP4)2011/2/15 ???????????????????????????????RAC ????????????????(WMV)??(MP4)2012/1/23 ????????????????????????????????!Oracle Net ??????????????(WMV)??(MP4)2012/1/23 ?????????????????????????????:???????????????0??????(WMV)??(MP4)2010/5/19 ???????????????????????????!???????????????????????(WMV)??(MP4)2012/1/23 ?????????Oracle Real Application Clusters????????????!RAC????????????????????(WMV)??(MP4)2011/3/1 ???????Core Tech Oracle Database Core Tech SeminarOracle Data Guard,Oracle Recovery Manager(RMAN),Flashback??(WMV)??(MP4)2012/5/14 ???????Core Tech Oracle Database Core Tech SeminarOracle Real Application Clusters,Oracle Clusterware,Oracle Automatic Storage Management??(WMV)??(MP4)2012/5/14 ???????Big Data Appliance?????????????????????(WMV)??(MP4)2012/5/14 ???????Oracle Real Application ClustersRAC????10??!US Oracle??????????????Oracle Real Application Clusters????????????(WMV)??(MP4)2012/2/20 ???????Oracle Enterprise Manager 12cOracle Enterprise Manager 12c ???????(WMV)??(MP4)2012/1/23 ???????Oracle Enterprise Manager 12cOracle Enterprise Manager 12c ???????/?????????? ????(WMV)??(MP4)2012/1/23 ???????Oracle Enterprise Manager 12c Oracle Enterprise Manager 12c ???????/????????? ????(WMV)??(MP4)2012/1/23 ???????Oracle Enterprise Manager 12cOracle Enterprise Manager 12c ??????? ????(WMV)??(MP4)2012/1/23 ???????Oracle Enterprise Manager 12cOracle Enterprise Manager 12c ??????? ????(WMV)??(MP4)2012/1/23 ???????Oracle Enterprise Manager 12cOracle Enterprise Manager 12c ????????? ????(WMV)??(MP4)2012/1/23 ???????Oracle Enterprise Manager 12cOracle Enterprise Manager 12c ????????? ????(WMV)??(MP4)2012/1/23 ???????Oracle Enterprise Manager 12cOracle Enterprise Manager 12c Exadata?????(WMV)??(MP4)2012/1/23 ???????Oracle Enterprise Manager 12cOracle Enterprise Manager 12c ???????????(WMV)??(MP4)2012/2/6 ???????Oracle Enterprise Manager 12cOracle Enterprise Manager???????????·?????????????(WMV)??(MP4)2012/5/14 ???????Database Appliance???????????1Box?????2???????? Oracle Database Appliance ??????(WMV)??(MP4)2011/12/19 ???????Database ApplianceOracle Database Appliance????????·????????(WMV)??(MP4)2012/5/14 ???????Oracle Data MiningOracle DB????!????????????(WMV)??(MP4)2010/9/14 ???????Oracle Data MiningOracleDB????????????(WMV)??(MP4)2011/6/29 OracleDirect ?????????????????!?????·???????ABC -Oracle Database???(WMV)??(MP4)2012/3/5 OracleDirect ???????????????????????-SE·EE??????-??(WMV)??(MP4)2010/5/19 OracleDirect ?????????????Oracle Database EE?SE???????????!???(WMV)??(MP4)2010/2/25 OracleDirect ????????????????98(????)???Oracle Database?????????! ~?????????????Oracle Database?????!~??(WMV)??(MP4)2009/12/2 OracleDirect ????????????!! Oracle Database????????(WMV)??(MP4)2010/10/13 OracleDirect ?????SQL?????????SQL?????????!SQL?????(WMV)??(MP4)2011/4/12 ???????????ACE????? ??Oracle Database???????(WMV)??(MP4)2012/5/14 ???????????????????????????????????????????? ??(WMV)??(MP4)2012/1/23 ????????????????!?????????????????·???????????? ????(WMV)??(MP4)2012/1/23 ????????????????!?????????????????·???????????? ????(WMV)??(MP4)2012/1/23 Java ???? ?? ????????? ??? ?? Java??Java EEJava EE 6 ??(132page)??(WMV)??(MP4)2011/04 Java?????!???????Java?????????(WMV)??(MP4)2011/06 Java??Java???????·???????????(WMV)??(MP4)2012/01 Java??Oracle ???? Java ??????? ??(WMV)??(MP4)2011/03 WebLogic Server/????????·???? ???? ?? ????????? ??? ?? WebLogic Server????Oracle????????WebLogic ????(WMV)??(MP4)2012/1/23 WebLogic Server????:????????? FastSwap??????·???????(??) ??(WMV)??(MP4)- WebLogic Server????:???????????????????(??)??(WMV)??(MP4)- WebLogic Server????:????????? ?????????????????????·??????????????????????(CAT)(??) ??(WMV)??(MP4)- WebLogic Server????:????????? ???????????????????????:????????????????????(??) ??(WMV)??(MP4)- WebLogic Server????:????????? JRockit Mission Control(??)??(WMV)??(MP4)- WebLogic Server????:????????? JRockit Flight Recorder????WebLogic????????????(??)??(WMV)??(MP4)- WebLogic Server????:????????? ?????????????? ???????????(??)??(WMV)??(MP4)- WebLogic Server????/???????????????????????????????????WebLogic????????(WMV)??(MP4)2011/3/24 WebLogic Server????WebLogic Server?JDBC??????????(WMV)??(MP4)2010/6/17 WebLogic Server????Oracle WebLogic Server???????Web??????? -???-??(WMV)??(MP4)2010/2/17 WebLogic Server????????????????? WebLogic Server ?????????????? ??(WMV)??(MP4)2012/1/23 WebLogic Server????????????????!WebLogic Scripting Tool?????WLS???·??????(WMV)??(MP4)2012/1/23 WebLogic Server????????????????????????~Oracle WebLogic Server 11g~??(WMV)??(MP4)2010/2/10 WebLogic Server????????????????!EM???WebLogic?????(WMV)??(MP4)2010/5/27 WebLogic Server ?????????????????WebLogic Server???????????????(WMV)??(MP4)2010/3/24 WebLogic Server????Oracle???????????????????????·????!??(WMV)??(MP4)2011/5/26 WebLogic Server??·????????OracleAS???????WebLogic Server??????????(WMV)??(MP4)2010/4/22 WebLogic ServerExalogicOracle Exalogic Elastic Cloud ?? ~ Exalogic ??? ~??(WMV)??(MP4)2012/1/23 JRockit??JVM JRockit?? ??Update??(WMV)??(MP4)2011/03 CoherenceOracle Coherence ?????·????????????????(WMV)??(MP4)2012/1/23 CoherenceOracle Coherence ????????????????(WMV)??(MP4)2012/1/23 Coherence???????????!???!Oracle Coherence?????????????????????????(WMV)??(MP4)2012/1/23 Coherence????????????Coherence??????(WMV)??(MP4)2011/04 SOA/BPM/????? ???? ?? ????????? ??? ?? BPM???????????BPM?????????????? ??(WMV)??(MP4)2011/04 BPMBPM Suite 11g??????????????????(WMV)??(MP4)2011/03 CEP??????????????????????????CEP????????(WMV)??(MP4)2011/04 ????????? ???? ?? ????????? ??? ?? ?????????????????????!???·????????????(WMV)??(MP4)2010/5/25 ???????Notes??????????????(WMV)??(MP4)2010/5/20 ???????Notes??13?????????????????????!??(WMV)??(MP4)2010/4/20 ??????????????????????Notes?????????????(WMV)??(MP4)2010/3/17 ???????Mashup Award5 ????????????????????????????????·?????????(WMV)??(MP4)2010/2/23 ID??/?????? ???? ?? ????????? ??? ?? ID????????????????!!~OracleDB?????????????????????????(WMV)??(MP4)2012/1/23 ID?????????????!????ID????????????(WMV)??(MP4)2010/6/15 ID???????????!????DB?OS?????/???????????(WMV)??(MP4)2010/1/27 ??????????/???????????????·???????????(WMV)??(MP4)2011/04 ?????????????~???????????????????(WMV)??(MP4)2011/4/5 ??????????!??ID·??????????????????(WMV)??(MP4)2010/12/7 ???????????????·???????????(WMV)??(MP4)2010/6/23 ?????EPM/BI EPM/BI ??????? ???? ?? ????????? ??? ?? ???BI????????????BI?????~5W1H1T?~??(WMV)??(MP4)2010/3/17 ???BI????????????BI?????~?????????~??(WMV)??(MP4)2010/2/24 ???????BI?????????? -Evidence-based Management- ??????????(WMV)??(MP4)2010/2/18 ???BI????????????BI?????~???KPI?~??(WMV)??(MP4)2010/1/28 EPM/BI ???? ???? ?? ????????? ??? ?? ??BIEE?????????????????(WMV)??(MP4)2010/3/10 OS/??? ???? ?? ????????? ??? ?? ???Solaris??????Oracle Solaris??????(WMV)??(MP4)2010/10/14 ???SolarisSolaris 10 ?? ~????Solaris???~??(WMV)??(MP4)2010/9/14 ???ZFSZFS ???! ZFS ???????(???)??(WMV)??(MP4)2011/11/21 ???ZFSZFS ???! ??????????????????(WMV)??(MP4)2010/9/28 ???LinuxOracle Linux?Unbreakable Enterprise Kernel?????(WMV)??(MP4)2011/11/21 ???LinuxOracle Linux Unbreakable Enterprise Kernel?????????(WMV)??(MP4)2012/5/14 ???Linux??????Oracle?????????Linux????(WMV)??(MP4)2010/5/25 ????????????????????????????????????(WMV)??(MP4)2012/1/6 ???????SolarisSolaris: ??????????????? ??(WMV)??(MP4)2011/1/27 ???????SolarisOracle Solaris 11????????????????? ??(WMV)??(MP4)2012/5/14 ???????SolarisSolaris ? DTrace ?????????????(WMV)??(MP4)2010/9/21 ???SolarisOracle Solaris 11 ??????????????-IPS ??????? ??(WMV)??(MP4)2012/5/14 ???SolarisSolaris ?????????????????????????????? ??(WMV)??(MP4)2012/5/14 ???ZFSZFS?Oracle UCM????????????? ??(WMV)??(MP4)2011/12/19 ???? ???? ?? ????????? ??? ?? ???SPARCSPARC ????? ~ OVM ???????!??(WMV)??(MP4)2011/12/5 ????? ???? ?? ????????? ??? ?? ???SAN????????????? Pillar Axiom 600 ???? ??(WMV)??(MP4)2012/4/23 ???ZFSOracleDB????SunStorage7000?????(WMV)??(MP4)2010/9/9 ????????!??????????????????????(WMV)??(MP4)2012/2/6 ???ZFS??S7000???:S7000????????????(WMV)??(MP4)2011/12/5 MySQL ???? ?? ????????? ??? ?? MySQL????MySQL????MySQL?????? ????????(WMV)??(MP4)2011/7/25 MySQL???MySQL??MySQL?? ?????(WMV)??(MP4)2012/1/23 MySQL???MySQL??MySQL?? ?????(WMV)??(MP4)2012/5/28 MySQL???MySQL??MySQL?? ???????(WMV)??(MP4)2012/6/25 MySQL???MySQL??MySQL???????(WMV)??(MP4)2011/7/25 MySQL????????????????MySQL ???????????????(WMV)??(MP4)2012/1/23 MySQL???MySQL Cluster MySQL Cluster ??????(WMV)??(MP4)2012/2/6 MySQL???MySQL Cluster MySQL Cluster 7.2 ??????(WMV)??(MP4)2012/3/19 MySQL??????? MySQL ????????(WMV)??(MP4)2012/2/6

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  • Oracle Launches New Oracle Database 12c Administrator Certifications

    - by Brandye Barrington
    Today Oracle University announces the release of new Oracle Database 12c Administrator certifications. The new Oracle Database 12c certifications emphasize the foundational and advanced skills needed by Database Administrators and will prepare DBAs to leverage powerful new management and consolidation capabilities, resulting in an even more valuable credential for customers and partners. ORACLE CERTIFIED ASSOCIATE (OCA)  The Oracle Certified Associate (OCA) for Oracle Database 12c objectives measure IT professionals' mastery of day-to-day administration skills and their ability to manage the challenges they're likely to encounter on the job. This credential focuses on SQL skills, operational administration of the Oracle Database including performance and space management, and installing, patching and upgrading the Oracle Database. Earning the OCA credential requires successful completion of two exams: 1Z0-061 - Oracle Database 12c: SQL Fundamentals and 1Z0-062 - Oracle Database 12c: Installation and Administration. The OCA certification track also allows for several alternate exams which can be substituted for 1Z0-061. ORACLE CERTIFIED PROFESSIONAL (OCP) Building on the competencies in the Oracle Database 12c OCA certification, the Oracle Certified Professional (OCP) for Oracle Database 12c certification includes advanced knowledge and skills required of top-performing database administrators. The OCP credential focuses on developing and implementing backup and recovery strategies, designing consolidation strategies to exploit multitenant container and pluggable databases, and thorough understanding how CDB/PDBs fit into the DBaaS cloud-computing model. Today, Oracle is releasing 1Z0-060 - Upgrade to Oracle Database 12c, which allows Oracle Certified Professionals with credentials in Oracle 9i, Oracle Database 10g or Oracle Database 11g to upgrade to Oracle Database 12c with a single exam. The upgrade exam focuses on designing consolidation strategies to exploit multitenant container and pluggable databases, implementing Oracle 12c feature-rich ILM support, optimizing SQL execution using dynamic swapping of sub plans, implementing real-time data redaction within databases, as well as exploiting many additional performance, backup and recovery, security and partitioning enhancements. The exam also includes a thorough review of core DBA skills. Visit the OCP certification track for more details on the new upgrade exam as well as alternate certification paths. ORACLE CERTIFIED MASTER (OCM) The Oracle Certified Master (OCM) for Oracle Database 12c - a very challenging and elite top-level certification - certifies the most highly skilled and experienced database experts. Further information on the 12c OCM level will be announced as exam development concludes. To date, there have been more than 1.6 million Oracle certifications granted worldwide. Explore these certification tracks, exam requirements and objectives, and start toward earning your exciting new Oracle Database 12c certification credentials from Oracle.

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  • What advantages do we have when creating a separate mapping table for two relational tables

    - by Pankaj Upadhyay
    In various open source CMS, I have noticed that there is a separate table for mapping two relational tables. Like for categories and products, there is a separate product_category_mapping table. This table just has a primary key and two foreign keys from the categories and product tables. My question is what are the benefits of this database design rather than just linking the tables directly by defining a foreign key in either table? Is it just matter of convenience?

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