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  • How can I efficiently manipulate 500k records in SQL Server 2005?

    - by cdeszaq
    I am getting a large text file of updated information from a customer that contains updates for 500,000 users. However, as I am processing this file, I often am running into SQL Server timeout errors. Here's the process I follow in my VB application that processes the data (in general): Delete all records from temporary table (to remove last month's data) (eg. DELETE * FROM tempTable) Rip text file into the temp table Fill in extra information into the temp table, such as their organization_id, their user_id, group_code, etc. Update the data in the real tables based on the data computed in the temp table The problem is that I often run commands like UPDATE tempTable SET user_id = (SELECT user_id FROM myUsers WHERE external_id = tempTable.external_id) and these commands frequently time out. I have tried bumping the timeouts up to as far as 10 minutes, but they still fail. Now, I realize that 500k rows is no small number of rows to manipulate, but I would think that a database purported to be able to handle millions and millions of rows should be able to cope with 500k pretty easily. Am I doing something wrong with how I am going about processing this data? Please help. Any and all suggestions welcome.

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  • EFv1 mapping 1 to many Relationship to POCOs

    - by Scott
    I'm trying to work through a problem where I'm mapping EF Entities to POCO which serve as DTO. I have two tables within my database, say Products and Categories. A Product belongs to one category and one category may contain many Products. My EF entities are named efProduct and efCategory. Within each entity there is the proper Navigation Property between efProduct and efCategory. My Poco objects are simple public class Product { public string Name { get; set; } public int ID { get; set; } public double Price { get; set; } public Category ProductType { get; set; } } public class Category { public int ID { get; set; } public string Name { get; set; } public List<Product> products { get; set; } } To get a list of products I am able to do something like public IQueryable<Product> GetProducts() { return from p in ctx.Products select new Product { ID = p.ID, Name = p.Name, Price = p.Price ProductType = p.Category }; } However there is a type mismatch error because p.Category is of type efCategory. How can I resolve this? That is, how can I convert p.Category to type Category? I know in .NET EF has added support for POCO, but I'm forced to use .NET 3.5 SP1.

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  • Unable to delete inherited entity class in EF4

    - by Coding Gorilla
    I have two entities in an EF4 model (using Model First), let's call them EntityA and EntityB. EntityA is marked as abstract, and EntityB inherits from EntityA. They are similar to the following: public class EntityA { public Guid Id; public string Name; public string Uri; } public class EntityB : EntityA { public string AnotherProperty; } The generated database tables look as I would expect them, with EntityA as on table, and then another table like: EntityA_EntityB Id (PK, FK, uniqueidentifier) AnotherProperty (varchar) There is a foreign key constraint on EntityA_EntityB that references EntityA's Id property, no cascades are configured (although I did try changing these myself). The problem is that when I attempt to do something like: Context.DeleteObject(EntityA_EntityB); EF attempts to delete the EntityA_EntityB table record before deleting the EntityA table record, which of course violates the foreign key constraint on EntityA_EntityB table. Using EFProfiler I see the following commands being sent to the database: delete [dbo].[EntityA_EntityB] where (([Id] = '5c02899f-09ea-2ed9-d44b-01aef80f6b64' /* @0 */) followed by delete [dbo].[EntityA] where ([Id] = '5c02899f-09ea-2ed9-d44b-01aef80f6b64' /* @0 */) I'm completely stumped as to how to get around this problem. I would think the EF should know that it needs to delete the base class first, before deleting the inherited class. I know I could do some triggers or other database type solutions, but I'd rather avoid doing that if I can. All my classes are POCO built using some customized T4 templates. I don't want to paste in a lot of extraneous code, but if you need more information I'll provide what I can.

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  • How to map oracle timestamp to appropriate java type in hibernate?

    - by jschoen
    I am new to hibernate and I am stumped. In my database I have tables that have a columns of TIMESTAMP(6). I am using Netbeans 6.5.1 and when I generate the hibernate.reveng.xml, hbm.xml files, and pojo files it sets the columns to be of type Serializable. This is not what I expected, nor what I want them to be. I found this post on the hibernate forums saying to place: in the hibernate.reveng.xml file. In Netbeans you are not able to generate the mappings from this file (it creates a new one every time) and it does not seem to have the ability to re-generate them from the file either (at least according to this it is slated to be available in version 7). So I am trying to figure out what to do. I am more inclined to believe I am doing something wrong since I am new to this, and it seems like it would be a common problem for others. So what am I doing wrong? If I am not doing anything wrong, how do I work around this? I am using Netbeans 6.5, Oracle 10G, and I believe Hibernate 3 (it came with my netbeans). Edit: Meant to say I found this stackoverflow question, but it is really a different problem.

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  • Computation overhead in C# - Using getters/setters vs. modifying arrays directly and casting speeds

    - by Jeffrey Kern
    I was going to write a long-winded post, but I'll boil it down here: I'm trying to emulate the graphical old-school style of the NES via XNA. However, my FPS is SLOW, trying to modify 65K pixels per frame. If I just loop through all 65K pixels and set them to some arbitrary color, I get 64FPS. The code I made to look-up what colors should be placed where, I get 1FPS. I think it is because of my object-orented code. Right now, I have things divided into about six classes, with getters/setters. I'm guessing that I'm at least calling 360K getters per frame, which I think is a lot of overhead. Each class contains either/and-or 1D or 2D arrays containing custom enumerations, int, Color, or Vector2D, bytes. What if I combined all of the classes into just one, and accessed the contents of each array directly? The code would look a mess, and ditch the concepts of object-oriented coding, but the speed might be much faster. I'm also not concerned about access violations, as any attempts to get/set the data in the arrays will done in blocks. E.g., all writing to arrays will take place before any data is accessed from them. As for casting, I stated that I'm using custom enumerations, int, Color, and Vector2D, bytes. Which data types are fastest to use and access in the .net Framework, XNA, XBox, C#? I think that constant casting might be a cause of slowdown here. Also, instead of using math to figure out which indexes data should be placed in, I've used precomputed lookup tables so I don't have to use constant multiplication, addition, subtraction, division per frame. :)

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  • Kohana Auth Library Deployment

    - by Steve
    My Kohana app runs perfectly on my local machine. When I deployed my app to a server (and adjust the config files appropriately), I can no longer log into the app. I've traced through the app login routine on both my local version and the server version and they both agree with each other all the way through until you get to the auth.php controller logged_in() routine where suddenly, at line 140 - the is_object($this-user) test - the $user object no longer exists!?!?!? The login() function call that calls the logged_in() function successfully passes the following test, which causes a redirect to the logged_in() function. if(Auth::instance()->login($user, $post['password'])) Yes, the password and hash, etc all work perfectly. Here is the offending code: public function logged_in() { if ( ! is_object($this->user)) { // No user is currently logged in url::redirect('auth/login'); } etc... } As the code is the same between my local installation and the server, I reckon it must be some server setting that is messing with me. FYI: All the rest of the code works because I have a temporary backdoor available that allows me to use the application (view pages of tables, etc) without being logged in. Any ideas?

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  • Index question: Select * with WHERE clause. Where and how to create index

    - by Mestika
    Hi, I’m working on optimizing some of my queries and I have a query that states: select * from SC where c_id ="+c_id” The schema of ** SC** looks like this: SC ( c_id int not null, date_start date not null, date_stop date not null, r_t_id int not null, nt int, t_p decimal, PRIMARY KEY (c_id, r_t_id, date_start, date_stop)); My immediate bid on how the index should be created is a covering index in this order: INDEX(c_id, date_start, date_stop, nt, r_t_id, t_p) The reason for this order I base on: The WHERE clause selects from c_id thus making it the first sorting order. Next, the date_start and date_stop to specify a sort of “range” to be defined in these parameters Next, nt because it will select the nt Next the r_t_id because it is a ID for a specific type of my r_t table And last the t_p because it is just a information. I don’t know if it is at all necessary to order it in a specific way when it is a SELECT ALL statement. I should say, that the SC is not the biggest table. I can say how many rows it contains but a estimate could be between <10 and 1000. The next thing to add is, that the SC, in different queries, inserts the data into the SC, and I know that indexes on tables which have insertions can be cost ineffective, but can I somehow create a golden middle way to effective this performance. Don't know if it makes a different but I'm using IBM DB2 version 9.7 database Sincerely Mestika

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  • Postgresql Output column from another table

    - by muffin
    i'm using Postgresql, my question is specifically about querying from a table that's in another table and i'm really having trouble with this one. In fact, i'm absolutely mentally blocked. I'll try to define the relations of the tables as much as I can. I have a table entry which is like this: Each of the entries has a group_id; when they are 'advanced' to the next stage, the old entries are marked is_active = false, and a new assignment is done, so C & D are advanced stages of A & B. I have another table (which acts as a record keeper) , in which the storage_log_id refers to, this is the storage_log table : But then I have another table, to really find out where the entries are actually stored - storage table : To define my problem properly. Each entry has a storage_log_id (but some doesn't have yet), and a storage_log has a storage_id to refer to the actual table and find the storage label. The sql query i'm trying to do should output this one: Where The actual storage label is shown instead of the log id. This is so far what i've done: select e.id, e.group_id, e.name, e.stage, s.label from operational.entry e, operational.storage_log sl, operational.storage s where e.storage_log_id = sl.id and sl.storage_id = s.id But this just returns 3 rows, showing only the ones that have the seed_storage_log_id set; I should be able to see even those without logs, and especially the active ones. adding e.is_active = true to the condition makes the results empty. So, yeah i'm stuck. Need help, Thanks guys!

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  • performance issue: difference between select s.* vs select *

    - by kamil
    Recently I had some problem in performance of my query. The thing is described here: poor Hibernate select performance comparing to running directly - how debug? After long time of struggling, I've finally discovered that the query with select prefix like: select sth.* from Something as sth... Is 300x times slower then query started this way: select * from Something as sth.. Could somebody help me, and asnwer why is that so? Some external documents on this would be really useful. The table used for testing was: SALES_UNIT table contains some basic info abot sales unit node such as name and etc. The only association is to table SALES_UNIT_TYPE, as ManyToOne. The primary key is ID and field VALID_FROM_DTTM which is date. SALES_UNIT_RELATION contains relation PARENT-CHILD between sales unit nodes. Consists of SALES_UNIT_PARENT_ID, SALES_UNIT_CHILD_ID and VALID_TO_DTTM/VALID_FROM_DTTM. No association with any tables. The PK here is ..PARENT_ID, ..CHILD_ID and VALID_FROM_DTTM The actual query I've done was: select s.* from sales_unit s left join sales_unit_relation r on (s.sales_unit_id = r.sales_unit_child_id) where r.sales_unit_child_id is null select * from sales_unit s left join sales_unit_relation r on (s.sales_unit_id = r.sales_unit_child_id) where r.sales_unit_child_id is null Same query, both uses left join and only difference is with select.

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  • LINQ to SQL - database relationships won't update after submit

    - by Quantic Programming
    I have a Database with the tables Users and Uploads. The important columns are: Users -> UserID Uploads -> UploadID, UserID The primary key in the relationship is Users -> UserID and the foreign key is Uploads -> UserID. In LINQ to SQL, I do the following operations: Retrieve files var upload = new Upload(); upload.UserID = user.UserID; upload.UploadID = XXX; db.Uploads.InsertOnSubmit(upload) db.SubmitChanges(); If I do that and rerun the application (and the db object is re-built, of course) - if do something like this: foreach(var upload in user.Uploads) I get all the uploads with that user's ID. (like added in the previous example) The problem is, that my application, after adding an upload an submitting changes, doesn't update the user.Uploads collection. i.e - I don't get the newly added uploads. The user object is stored in the Session object. At first, I though that the LINQ to SQL Framework doesn't update the reference of the object, therefore I should simply "reset" the user object from a new SQL request. I mean this: Session["user"] = db.Users.Where(u => u.UserID == user.UserID).SingleOrDefault(); (Where user is the previous user) But it didn't help. Please note: After rerunning the application, user.Uploads does have the new upload! Did anyone experience this type of problem, or is it normal behavior? I am a newbie to this framework. I would gladly take any advice. Thank you!

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  • CodeIgniter: Where should a particular functionality go ?

    - by Samnan
    I have an application in codeigniter and a page needs to perform the following tasks 1 - controller decides which model to use based of the url and parameters 2 - controller loads the model and get the data from it 3 - controller formats the data in a particular format, depending on the items in it 4 - controller loads a common view, which will display the data (formatted data contains simple display fields) now there is a search page, which needs to do a text query against all of the possible text fields in database in all tables. It needs to show each type of data in its own formatted output on a single page as a list. The problem: The search controller can do the search, dynamically load model for each record type, and get the data from model. Problem comes when the data needs to be formatted. It looks that ideally the search controller should load another controller which will provide formatted data ... There is where it gets out of control ... My question is: What am I doing wrong? Is there any better way to do this? How would you do the same to solve the problem?

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  • Why can't we just use a hash of passphrase as the encryption key (and IV) with symmetric encryption algorithms?

    - by TX_
    Inspired by my previous question, now I have a very interesting idea: Do you really ever need to use Rfc2898DeriveBytes or similar classes to "securely derive" the encryption key and initialization vector from the passphrase string, or will just a simple hash of that string work equally well as a key/IV, when encrypting the data with symmetric algorithm (e.g. AES, DES, etc.)? I see tons of AES encryption code snippets, where Rfc2898DeriveBytes class is used to derive the encryption key and initialization vector (IV) from the password string. It is assumed that one should use a random salt and a shitload of iterations to derive secure enough key/IV for the encryption. While deriving bytes from password string using this method is quite useful in some scenarios, I think that's not applicable when encrypting data with symmetric algorithms! Here is why: using salt makes sense when there is a possibility to build precalculated rainbow tables, and when attacker gets his hands on hash he looks up the original password as a result. But... with symmetric data encryption, I think this is not required, as the hash of password string, or the encryption key, is never stored anywhere. So, if we just get the SHA1 hash of password, and use it as the encryption key/IV, isn't that going to be equally secure? What is the purpose of using Rfc2898DeriveBytes class to generate key/IV from password string (which is a very very performance-intensive operation), when we could just use a SHA1 (or any other) hash of that password? Hash would result in random bit distribution in a key (as opposed to using string bytes directly). And attacker would have to brute-force the whole range of key (e.g. if key length is 256bit he would have to try 2^256 combinations) anyway. So either I'm wrong in a dangerous way, or all those samples of AES encryption (including many upvoted answers here at SO), etc. that use Rfc2898DeriveBytes method to generate encryption key and IV are just wrong.

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  • Hibernate NamingStrategy implementation that maintains state between calls

    - by Robert Petermeier
    Hi, I'm working on a project where we use Hibernate and JBoss 5.1. We need our entity classes to be mapped to Oracle tables that follow a certain naming convention. I'd like to avoid having to specify each table and column name in annotations. Therefore, I'm currently considering implementing a custom implementation of org.hibernate.cfg.NamingStrategy. The SQL naming conventions require the name of columns to have a suffix that is equivalent to a prefix of the table name. If there is a table "T100_RESOURCE", the ID column would have to be named "RES_ID_T100". In order to implement this in a NamingStrategy, the implementation would have to maintain state, i.e. the current class name it is creating the mappings for. It would rely on Hibernate to always call classToTableName() before propertyToColumnName() and to determine all column names by calling propertyToColumnName() before the next call to classToTableName() Is it safe to do that or are there situations where Hibernate will mix things up? I am not thinking of problems through multiple threads here (which can be solved by keeping the last class name in a ThreadLocal) but also of Hibernate deliberately calling this out of order in certain circumstances. For example Hibernate asking for mappings of three properties of class A, then one of class B, then again more attributes of class A.

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  • MySQL running on an EC2 m1.small instance has high load but low memory usage, possible resolutions?

    - by Tosh
    I have a MySQL server 5.0.75 Ubuntu, on an m1.small instance running on Amazon's EC2 as part of an application. During peak usage the server load will rise very high, while the memory usage stays low and the application server is no longer responsive since it's waiting for query results. The application server has only 5-8 apache processes running (mod_perl processes). The data directory uses only 140MB of data so the MyIsam tables aren't very big. The queries are pretty complicated with some big joins being performed, and the application makes a lot of queries. mysqltuner reports everything OK except "Maximum possible memory usage: 1.7G (99% of installed RAM)" but I'm nowhere close to using that. My question is, where should I be looking to fix this? Is this something that can be tuned away, or do I just need a larger instance/server? Googling indicates either or also upgrading MySQL server. Any pointers in the right direction would be greatly appreciated, thanks! EDIT: I just discovered this in my slow queries log: # Time: 101116 11:17:00 # User@Host: user[pass] @ [host] # Query_time: 4063 Lock_time: 1035 Rows_sent: 0 Rows_examined: 19960174 SELECT * FROM contacts WHERE contacts.contact_id IN (SELECT external_id FROM contact_relations WHERE external_table = 'contacts' AND contact_id IN (SELECT contact_id FROM contacts WHERE (company_name like '%%butan%%%' OR country like '%%butan%%%' OR city like '%%butan%%%' OR email1 like '%%butan%%%') AND (company_name is not null and company_name != ''))); Which actually brings up a different but related question: If I have a contact table containing: John Smith,The Fun Factory,555-1212,[email protected] What's the best way to search for that record using "factory" as a search key? Fulltext rarely seems to find items in the middle of a word, for example "actor" should bring up "Factory"

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  • Why does the WCF 3.5 REST Starter Kit do this?

    - by Brandon
    I am setting up a REST endpoint that looks like the following: [WebInvoke(Method = "POST", UriTemplate = "?format=json", BodyStyle = WebMessageBodyStyle.WrappedRequest, ResponseFormat = WebMessageFormat.Json)] and [WebInvoke(Method = "DELETE", UriTemplate = "?token={token}&format=json", ResponseFormat = WebMessageFormat.Json)] The above throws the following error: UriTemplateTable does not support '?format=json' and '?token={token}&format=json' since they are not equivalent, but cannot be disambiguated because they have equivalent paths and the same common literal values for the query string. See the documentation for UriTemplateTable for more detail. I am not an expert at WCF, but I would imagine that it should map first by the HTTP Method and then by the URI Template. It appears to be backwards. If both of my URI templates are: ?token={token}&format=json This works because they are equivalent and it then appears to look at the HTTP Method where one is POST and the other is DELETE. Is REST supposed to work this way? Why are the URI Template Tables not being sorted first by HTTP Method and then by URI Template? This can cause some serious frustrations when 1 HTTP Method requires a parameter and another does not, or if I want to do optional parameters (e.g. if the 'format' parameter is not passed, default to XML).

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  • Query returning related assets

    - by GMo
    I have 2 tables, one is an assets table which holds digital assets (e.g. article, images etc), the 2nd table is an asset_links table which maps 1-1 relationships between assets contained within the assets table. Here are the table definitions: Asset +---------------+--------------+------+-----+---------+----------------+ | Field | Type | Null | Key | Default | Extra | +---------------+--------------+------+-----+---------+----------------+ | id | int(11) | NO | PRI | NULL | auto_increment | | source | varchar(255) | YES | | NULL | | | title | varchar(255) | YES | | NULL | | | date_created | datetime | YES | | NULL | | | date_embargo | datetime | YES | | NULL | | | date_expires | datetime | YES | | NULL | | | date_updated | datetime | YES | | NULL | | | keywords | varchar(255) | YES | | NULL | | | status | int(11) | YES | | NULL | | | priority | int(11) | YES | | NULL | | | fk_site | int(11) | YES | MUL | NULL | | | resource_type | varchar(255) | YES | | NULL | | | resource_id | int(11) | YES | | NULL | | | fk_user | int(11) | YES | MUL | NULL | | +---------------+--------------+------+-----+---------+----------------+ Asset_links +-----------+---------+------+-----+---------+----------------+ | Field | Type | Null | Key | Default | Extra | +-----------+---------+------+-----+---------+----------------+ | id | int(11) | NO | PRI | NULL | auto_increment | | asset_id1 | int(11) | YES | | NULL | | | asset_id2 | int(11) | YES | | NULL | | +-----------+---------+------+-----+---------+----------------+ In the asset_links table there are the following rows: 1 - 3, 1 - 4, 2 - 10, 2 - 56 I am looking to write one query which will return all assets which satisfy any asset search criteria and within the same query return all of the linked asset data for linked assets for that asset. e.g. The query returning assets 1 and 2 would return : Asset 1 attributes - Asset 3 attributes - Asset 4 attributes Asset 2 attributes - Asset 10 attributes - Asset 56 attributes What is the best way to write the query?

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  • Java: over-typed structures?

    - by HH
    Term over-type structure = a data structure that accepts different types, can be primitive or user-defined. I think ruby supports many types in structures such as tables. I tried a table with types 'String', 'char' and 'File' in Java but errs. How can I have over-typed structure in Java? How to show types in declaration? What about in initilization? Suppose a structure: INDEX VAR FILETYPE //0 -> file FILE //1 -> lineMap SizeSequence //2 -> type char //3 -> binary boolean //4 -> name String //5 -> path String Code import java.io.*; import java.util.*; public class Object { public static void print(char a) { System.out.println(a); } public static void print(String s) { System.out.println(s); } public static void main(String[] args) { Object[] d = new Object[6]; d[0] = new File("."); d[2] = 'T'; d[4] = "."; print(d[2]); print(d[4]); } } Errors Object.java:18: incompatible types found : java.io.File required: Object d[0] = new File("."); ^ Object.java:19: incompatible types found : char required: Object d[2] = 'T'; ^

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  • Can a Snapshot transaction fail and only partially commit in a TransactionScope?

    - by Travis Brooks
    Greetings I stumbled onto a problem today that seems sort of impossible to me, but its happening...I'm calling some database code in c# that looks something like this: using(var tran = MyDataLayer.Transaction()) { MyDataLayer.ExecSproc(new SprocTheFirst(arg1, arg2)); MyDataLayer.CallSomethingThatEventuallyDoesLinqToSql(arg1, argEtc); tran.Commit(); } I've simplified this a bit for posting, but whats going on is MyDataLayer.Transaction() makes a TransactionScope with the IsolationLevel set to Snapshot and TransactionScopeOption set to Required. This code gets called hundreds of times a day, and almost always works perfectly. However after reviewing some data I discovered there are a handful of records created by "SprocTheFirst" but no corresponding data from "CallSomethingThatEventuallyDoesLinqToSql". The only way that records should exist in the tables I'm looking at is from SprocTheFirst, and its only ever called in this one function, so if its called and succeeded then I would expect CallSomethingThatEventuallyDoesLinqToSql would get called and succeed because its all in the same TransactionScope. Its theoretically possible that some other dev mucked around in the DB, but I don't think they have. We also log all exceptions, and I can find nothing unusual happening around the time that the records from SprocTheFirst were created. So, is it possible that a transaction, or more properly a declarative TransactionScope, with Snapshot isolation level can fail somehow and only partially commit?

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  • Multiple left joins, how to output in php

    - by Dan
    I have 3 tables I need to join. The contracts table is the main table, the 'jobs' and 'companies' table are extra info that can be associated to the contracts table. so, since I want all entries from my 'contracts' table, and the 'jobs' and 'companies' data only if it exists, I wrote the query like this.... $sql = "SELECT * FROM contracts LEFT JOIN jobs ON contracts.job_id = jobs.id LEFT JOIN companies ON contracts.company_id = companies.id ORDER BY contracts.end_date"; Now how would I output this in PHP? I tried this but kept getting an undefined error "Notice: Undefined index: contracts.id"... $sql_result = mysql_query($sql,$connection) or die ("Fail."); if(mysql_num_rows($sql_result) > 0){ while($row = mysql_fetch_array($sql_result)) { $contract_id = stripslashes($row['contracts.id']); $job_number = stripslashes($row['jobs.job_number']); $company_name = stripslashes($row['companies.name']); ?> <tr id="<?=$contract_id?>"> <td><?=$job_number?></td> <td><?=$company_name?></td> </tr> <? } }else{ echo "No records found"; } Any help is appreciated.

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  • Guidance required: FIrst time gonna work with real high end database (size = 50GB).

    - by claws
    I got a project of designing a Database. This is going to be my first big scale project. Good thing about it is information is mostly organized & currently stored in text files. The size of this information is 50GB. There are going to be few millions of records in each Table. Its going to have around 50 tables. I need to provide a web interface for searching & browsing. I'm going to use MySQL DBMS. I've never worked with a database more than 200MB before. So, speed & performance was never a concern but I followed things like normalization & Indexes. I never used any kind of testing/benchmarking/queryOptimization/whatever because I never had to care about them. But here the purpose of creating a database is to make it quickly searchable. So, I need to consider all possible aspects in design. I was browsing archives & found: http://stackoverflow.com/questions/1981526/what-should-every-developer-know-about-databases http://stackoverflow.com/questions/621884/database-development-mistakes-made-by-app-developers I'm gonna keep the points mentioned in above answers in mind. What else should I know? What else should I keep in mind?

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  • Best way to limit results in MySQL with user subcategories

    - by JM4
    I am trying to essentially solve for the following: 1) Find all users in the system who ONLY have programID 1. 2) Find all users in the system who have programID 1 AND any other active program. My tables structures (in very simple terms are as follows): users userID | Name ================ 1 | John Smith 2 | Lewis Black 3 | Mickey Mantle 4 | Babe Ruth 5 | Tommy Bahama plans ID | userID | plan | status --------------------------- 1 | 1 | 1 | 1 2 | 1 | 2 | 1 3 | 1 | 3 | 1 4 | 2 | 1 | 1 5 | 2 | 3 | 1 6 | 3 | 1 | 0 7 | 3 | 2 | 1 8 | 3 | 3 | 1 9 | 3 | 4 | 1 10 | 4 | 2 | 1 11 | 4 | 4 | 1 12 | 5 | 1 | 1 I know I can easily find all members with a specific plan with something like the following: SELECT * FROM users a JOIN plans b ON (a.userID = b.userID) WHERE b.plan = 1 AND b.status = 1 but this will only tell me which users have an 'active' plan 1. How can I tell who ONLY has plan 1 (in this case only userID 5) and how to tell who has plan 1 AND any other active plan? Update: This is not to get a count, I will actually need the original member information, including all the plans they have so a COUNT(*) response may not be what I'm trying to achieve.

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  • Large Product catalog with statistics - alternatives to Sql Server?

    - by Eric P
    I am building UI for a large product catalog (millions of products). I am using Sql Server, FreeText search and ASP.NET MVC. Tables are normalized and indexed. Most queries take less then a second to return. The issue is this. Let's say user does the search by keyword. On search results page I need to display/query for: First 20 matching products (paged, sorted) Total count of matching products for paging List of stores only of matching products List of brands only of matching products List of colors only of matching products Each query takes about .5 to 1 seconds. Altogether it is like 5 seconds. I would like to get the whole page to load under 1 second. There are several approaches: Optimize queries even more. I already spent a lot of time on this one, so not sure it can be pushed further. Load products first, then load the rest of the information using AJAX. More like a workaround. Will need to revise UI. Re-organize data to be more Report friendly. Already aggregated a lot of fields. I checked out several similar sites. For ex. zappos.com. Not only they display the same information as I would like in under 1 second, but they also include statistics (number of results in each category). The following is the search for keyword "white" http://www.zappos.com/white How do sites like zappos, amazon make their results, filters and stats appear almost instantly?

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  • .net printing multiple reports in one document (architecture question)

    - by LawsonM
    I understand how to print a single document via the PrintDocument class. However, I want to print multiple reports in one document. Each "report" will consist of charts, tables, etc. I want to have two reports per page. I've studied the few examples I can find on how to combine multiple documents into one; however, they always seem to work by creating a collection of objects (e.g. customer or order) that are then iterated over and drawn in the OnPrintPage method. My problem and hence the "architecture" question is that I don't want to cache the objects required to produce the report since they are very large and memory intensive. I'd simply like the resulting "report". One thought I had was to print the report to a metafile, cache that instead in a "MultiplePrintDocument" class and then position those images appropriately two to a page in the OnPrintPage method. I think this would be a lot more efficient and scalable in my case. But I'm not a professional programmer and can't figure out if I'm barking up the wrong tree here. I think the Graphics.BeginContainer and Graphics.Save methods might be relevant, but can't figure out how to implement or if there is a better way. Any pointers would be greatly appreciated.

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  • Django Many-to-Many Question

    - by DZ
    My questions seems like a common problem that when I have seen any questions on it is never really asked right or not answered. So Im going to try to get the question right, and maybe someone knows how to resolve the issue, or correct my understanding. The problem: When you have a many-to-many relation ship (related_name not through) and you are trying to use the admin interface you are required to input one of the rleationships even though it does not have to exsist for you to create the first entry. Meaning you have to assign a group to an event to create the group. Wow that sounds complicated. So I can see why the question is not getting answered. Lets try the non code explanation example... First and important versions: Django 1.1.1 Phython 2.6 So I have a model where I created a many-to-many realtionship and Im using the related_name Im creating an app that is an event organizer, for simplicty lets say events although they could be anytype). For this first post Im going to stay away from the code and just try to explain. A few keys: (explaining comment) ** - many-to-many So in the model we have 1) The Main Event (this is main model) 2) Groups (link to events and their can be many events for a group) a) Events** I have simplified this example a little becuase I recognize that what does it matter. Just create the event first... But there are specific varations where that will not work. What the many-to-many related_name does it created another table with the indecies of the two other tables. Nothing says that this extra table HAS to be populated. Becuase if I look in the database and work within myPHPadmin I can create a group with out registering an event, since the connection between the two is a seperate table the DB does not care. How do I make the admin interface this realize it? Ok I know thats a lot so I hope I have explained it clearly. Thank you anyone for your comments/thoughts/advice

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  • Fix DB duplicate entries (MySQL bug)

    - by Silence
    I'm using MySQL 4.1. Some tables have duplicates entries that go against the constraints. When I try to group rows, MySQL doesn't recognise the rows as being similar. Example: Table A has a column "Name" with the Unique proprety. The table contains one row with the name 'Hach?' and one row with the same name but a square at the end instead of the '?' (which I can't reproduce in this textfield) A "Group by" on these 2 rows return 2 separate rows This cause several problems including the fact that I can't export and reimport the database. On reimporting an error mentions that a Insert has failed because it violates a constraint. In theory I could try to import, wait for the first error, fix the import script and the original DB, and repeat. In pratice, that would take forever. Is there a way to list all the anomalies or force the database to recheck constraints (and list all the values/rows that go against them) ? I can supply the .MYD file if it can be helpful.

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