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  • mysql query for getting all messages that belong to user's contacts

    - by aharon
    So I have a database that is setup sort of like this (simplified, and in terms of the tables, all are InnoDBs): Users: contains based user authentication information (uid, username, encrypted password, et cetera) Contacts: contains two rows per relationship that exists between users as (uid1, uid2), (uid2, uid1) to allow for a good 1:1 relationship (must be mutual) between users Messages: has messages that consist of a blob, owner-id, message-id (auto_increment) So my question is, what's the best MySQL query to get all messages that belong to all the contacts of a specific user? Is there an efficient way to do this?

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  • Query a range of date

    - by juniorSE
    Hello Guys, Im trying to query a sort of from - to date. e.g. 20-01-2010 to 20-02-2010. this should include the mentioned dates. i've tried the following queries but none works. select * from [tableName] where date = '20-01-2010' AND date <= '20-02-2010' the date where date is equal to 20-02-2010 does not show. i don't know why. select * from [tableName] where date between '20-01-2010' AND '20-02-2010' the mentioned dates is not included in the results. i want it to be included in the results. please help. thanks in advance! :)

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  • add row to a BindingSource gives different autoincrement value from whats saved into DB

    - by Ruben Trancoso
    I have a DataGridView that shows list of records and when I hit a insert button, a form should add a new record, edit its values and save it. I have a BindingSource bound to a DataGridView. I pass is as a parameter to a NEW RECORD form so // When the form opens it add a new row and de DataGridView display this new record at this time DataRowView currentRow; currentRow = (DataRowView) myBindindSource.AddNew(); when user confirm to save it I do a myBindindSource.EndEdit(); // inside the form and after the form is disposed the new row is saved and the bindingsorce position is updated to the new row DataRowView drv = myForm.CurrentRow; avaliadoTableAdapter.Update(drv.Row); avaliadoBindingSource.Position = avaliadoBindingSource.Find("ID", drv.Row.ItemArray[0]); The problem is that this table has a AUTOINCREMENT field and the value saved may not correspond the the value the bindingSource gives in EDIT TIME. So, when I close and open the DataGridView again the new rowd give its ID based on the available slot in the undelying DB at the momment is was saved and it just ignores the value the BindingSource generated ad EDIT TIME, Since the value given by the binding source should be used by another table as a foreingKey it make the reference insconsistent. There's a way to get the real ID was saved to the database?

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  • Search 2 Columns with 1 Input Field

    - by Norbert
    I have a db with two columns: first name and last name. The first name can have multiple words. Last name can contain hyphenated words. Is there a way to search both columns with only one input box? Database ID `First Name` `Last Name` 1 John Peter Doe 2 John Fubar 3 Michael Doe Search john peter returns id 1 john returns id 1,2 doe returns id 1,3 john doe returns id 1 peter john returns id 1 peter doe returns id 1 doe john returns id 1 I previously tried the following. Searching for John Doe: SELECT * FROM names WHERE ( `first` LIKE '%john%' OR `first` LIKE '%doe%' OR `last` LIKE '%john%' OR `last` LIKE '%doe%' ) which returns both 1 and 3

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  • Aggregate Functions on subsets of data based on current row values with SQL

    - by aasukisuki
    Hopefully that title makes sense... Let's say I have an employee table: ID | Name | Title | Salary ---------------------------- 1 | Bob | Manager | 15285 2 | Joe | Worker | 10250 3 | Al | Worker | 11050 4 | Paul | Manager | 16025 5 | John | Worker | 10450 What I'd like to do is write a query that will give me the above table, along with an averaged salary column, based on the employee title: ID | Name | Title | Salary | Pos Avg -------------------------------------- 1 | Bob | Manager | 15285 | 15655 2 | Joe | Worker | 10250 | 10583 3 | Al | Worker | 11050 | 10583 4 | Paul | Manager | 16025 | 15655 5 | John | Worker | 10450 | 10583 I've tried doing this with a sub-query along the lines of: Select *, (select Avg(e2.salary) from employee e2 where e2.title = e.title) from employee e But I've come to realize that the sub-query is executed first, and has no knowledge of the table alias'd e I'm sure I'm missing something REALLY obvious here, can anyone point me in the right diretion?

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  • How do views reduce code duplication?

    - by Debuger
    Hi! I read something like this about db views: Views are incredibly powerful and useful for one reason that stands out above all the other very good reasons. They reduce code duplication. That is, in most cases, the bottom line. If a query will be used in three or more places, then a view will drastically simplify your changes if the schema or query parameters change. I once had to edit 22 stored procedures to change some query logic. If the original architecture had utilized views, then I would have had only three changes. Can anyone explain to me how it works, and maybe give me some examples? Best regards!

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  • How to clean sys.conversation_endpoints

    - by Manjoor
    I have a table, a trigger on the table implemented using service broker. More than Half million records are inserted daily into the table. The asynchronous SP is used to check sveral condition by using inserted data and update other tables. It was running fine for last 1 month and the SP was get executed withing 2-3 seconds of insertion of record. But now it take more than 90 minute. At present sys.conversation_endpoints have too much records. (Note that all the table are truncated daily as I do not need those records day after) Other database activities are normal (average 60% CPU Utilization). Now where i need to look?? I can re-create database without any problem but i don't think it is a good way to resolve the problem

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  • archiving strategies and limitations of data in a table

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

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  • Subquery max sequence number

    - by Andy Levesque
    I'm hesitant to ask because I'm sure it's out there, but I just can't seem to come up with the keywords to find the answer. I'm stepping outside my boundaries by starting with subqueries (normally an Access user). I have a query that has TECH_ID, SEQ_NBR, and PELL_FT_AWD_AMT SELECT ISRS_V_NEED_ANAL_RESULT_PARENT.TECH_ID, ISRS_V_NEED_ANAL_RESULT_PARENT.AWD_YR, ISRS_V_NEED_ANAL_RESULT_PARENT.PELL_FT_AWD_AMT, ISRS_V_NEED_ANAL_RESULT_PARENT.SEQ_NBR FROM ISRS_V_NEED_ANAL_RESULT_PARENT GROUP BY ISRS_V_NEED_ANAL_RESULT_PARENT.TECH_ID, ISRS_V_NEED_ANAL_RESULT_PARENT.AWD_YR, ISRS_V_NEED_ANAL_RESULT_PARENT.PELL_FT_AWD_AMT, ISRS_V_NEED_ANAL_RESULT_PARENT.SEQ_NBR HAVING (((ISRS_V_NEED_ANAL_RESULT_PARENT.AWD_YR)="2013")) ORDER BY ISRS_V_NEED_ANAL_RESULT_PARENT.TECH_ID; What I want to return is add a subquery that selects only the max SEQ_NUM for each record, but I can't seem to get the syntax right. In the past I would cheat and have a separate query that first gave me the TECH_ID and max SEQ_NUM, and then have a second query that use the original table and the first query in a join to get the rest. How can I do this in one query? Example: TECH_ID SEQ_NUM PELL 1 1 4000 1 2 4000 1 3 5000 Using just the max of the sequence number still returns: 1; 2; 4000 and 1; 3; 5000 when I'm only wanting the latter.

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  • C# SqlDataAdapter not populating DataSet

    - by Wesley
    I have searched the net and searched the net only to not quite find the probably I am running into. I am currently having an issue getting a SqlDataAdapter to populate a DataSet. I am running Visual Studio 2008 and the query is being sent to a local instance of SqlServer 2008. If I run the query itself in SqlServer, I do get information. Code is as follows: string theQuery = "select Password from Employees where employee_ID = '@EmplID'"; SqlDataAdapter theDataAdapter = new SqlDataAdapter(); theDataAdapter.SelectCommand = new SqlCommand(theQuery, conn); theDataAdapter.SelectCommand.Parameters.Add("@EmplID", SqlDbType.VarChar).Value = "EmployeeName"; theDataAdapter.Fill(theSet); The code to read the dataset: foreach (DataRow theRow in theSet.Tables[0].Rows) { //process row info } If there is any more info I can supply please let me know.

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  • Round date to fiscal year

    - by Dave Jarvis
    The following database view rounds the date back to the closest fiscal year (April 1st): CREATE OR REPLACE VIEW FISCAL_YEAR_VW AS SELECT CASE WHEN to_number(to_char( SYSDATE, 'MM' )) < 4 THEN to_date('1-APR-'||to_char(add_months(SYSDATE, -12), 'YYYY'), 'dd-MON-yyyy') ELSE to_date('1-APR-'||to_char(SYSDATE, 'YYYY'), 'dd-MON-yyyy') END AS fiscal_year FROM dual; This allows us to calculate the current fiscal year based on today's date. How can this calculation be simplified or optimized?

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  • Linq2SQL vs NHibernate performance (have I gone mad?)

    - by HeavyWave
    I have written the following tests to compare performance of Linq2SQL and NHibernate and I find results to be somewhat strange. Mappings are straight forward and identical for both. Both are running against a live DB. Although I'm not deleting Campaigns in case of Linq, but that shouldn't affect performance by more than 10 ms. Linq: [Test] public void Test1000ReadsWritesToAgentStateLinqPrecompiled() { Stopwatch sw = new Stopwatch(); Stopwatch swIn = new Stopwatch(); sw.Start(); for (int i = 0; i < 1000; i++) { swIn.Reset(); swIn.Start(); ReadWriteAndDeleteAgentStateWithLinqPrecompiled(); swIn.Stop(); Console.WriteLine("Run ReadWriteAndDeleteAgentState: " + swIn.ElapsedMilliseconds + " ms"); } sw.Stop(); Console.WriteLine("Total Time: " + sw.ElapsedMilliseconds + " ms"); Console.WriteLine("Average time to execute queries: " + sw.ElapsedMilliseconds / 1000 + " ms"); } private static readonly Func<AgentDesktop3DataContext, int, EntityModel.CampaignDetail> GetCampaignById = CompiledQuery.Compile<AgentDesktop3DataContext, int, EntityModel.CampaignDetail>( (ctx, sessionId) => (from cd in ctx.CampaignDetails join a in ctx.AgentCampaigns on cd.CampaignDetailId equals a.CampaignDetailId where a.AgentStateId == sessionId select cd).FirstOrDefault()); private void ReadWriteAndDeleteAgentStateWithLinqPrecompiled() { int id = 0; using (var ctx = new AgentDesktop3DataContext()) { EntityModel.AgentState agentState = new EntityModel.AgentState(); var campaign = new EntityModel.CampaignDetail { CampaignName = "Test" }; var campaignDisposition = new EntityModel.CampaignDisposition { Code = "123" }; campaignDisposition.Description = "abc"; campaign.CampaignDispositions.Add(campaignDisposition); agentState.CallState = 3; campaign.AgentCampaigns.Add(new AgentCampaign { AgentState = agentState }); ctx.CampaignDetails.InsertOnSubmit(campaign); ctx.AgentStates.InsertOnSubmit(agentState); ctx.SubmitChanges(); id = agentState.AgentStateId; } using (var ctx = new AgentDesktop3DataContext()) { var dbAgentState = ctx.GetAgentStateById(id); Assert.IsNotNull(dbAgentState); Assert.AreEqual(dbAgentState.CallState, 3); var campaignDetails = GetCampaignById(ctx, id); Assert.AreEqual(campaignDetails.CampaignDispositions[0].Description, "abc"); } using (var ctx = new AgentDesktop3DataContext()) { ctx.DeleteSessionById(id); } } NHibernate (the loop is the same): private void ReadWriteAndDeleteAgentState() { var id = WriteAgentState().Id; StartNewTransaction(); var dbAgentState = agentStateRepository.Get(id); Assert.IsNotNull(dbAgentState); Assert.AreEqual(dbAgentState.CallState, 3); Assert.AreEqual(dbAgentState.Campaigns[0].Dispositions[0].Description, "abc"); var campaignId = dbAgentState.Campaigns[0].Id; agentStateRepository.Delete(dbAgentState); NHibernateSession.Current.Transaction.Commit(); Cleanup(campaignId); NHibernateSession.Current.BeginTransaction(); } Results: NHibernate: Total Time: 9469 ms Average time to execute 13 queries: 9 ms Linq: Total Time: 127200 ms Average time to execute 13 queries: 127 ms Linq lost by 13.5 times! Event with precompiled queries (both read queries are precompiled). This can't be right, although I expected NHibernate to be faster, this is just too big of a difference, considering mappings are identical and NHibernate actually executes more queries against the DB.

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  • Analysis services with non normalized table

    - by Uwe
    I have a table with several million rows. Each row represents a user session. There is a column called user which is not unique. There can be multiple sessions per user. I want to use Analysis services to get me the additional properties per user. Example: How many users (unique!) had a session longer than x minutes. How is that possible without changing the database. Note: there is no lookup-table and I cannot create one. What I am able of at the moment is to ask how many sessions were longer then x minutes.

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  • mysql result set joining existing table

    - by Yang
    is there any way to avoid using tmp table? I am using a query with aggregate function (sum) to generate the sum of each product: the result looks like this: product_name | sum(qty) product_1 | 100 product_2 | 200 product_5 | 300 now i want to join the above result to another table called products. so that i will have a summary like this: product_name | sum(qty) product_1 | 100 product_2 | 200 product_3 | 0 product_4 | 0 product_5 | 300 i know 1 way of doing this is the dump the 1st query result to a temp table then join it with products table. is there a better way?

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  • Merging sql queries to get different results by date

    - by pedalpete
    I am trying to build a 'recent events' feed and can't seem to get either my query correct, or figure out how to possible merge the results from two queries to sort them by date. One table holds games/, and another table holds the actions of these games/. I am trying to get the recent events to show users 1) the actions taken on games that are publicly visible (published) 2) when a new game is created and published. So, my actions table has actionId, gameid, userid, actiontype, lastupdate My games table has gameid, startDate, createdby, published, lastupdate I currently have a query like this (simplified for easy understanding I hope). SELECT actionId, actions.gameid, userid, actiontype, actions.lastupdate FROM actions JOIN ( SELECT games.gameid, startDate, createdby, published, games.lastupdate FROM games WHERE published=1 AND lastupdate>today-2 ) publishedGames on actions.gameid=games.gameid WHERE actions.type IN (0,4,5,6,7) AND actions.lastupdate>games.lastupdate and published=1 OR games.lastupdate>today-2 AND published=1 This query is looking for actions from published games where the action took place after the game was published. That pretty much takes care of the first thing that needs to be shown. However, I also need to get the results of the SELECT games.gameid, startDate, createdby, published, games.lastupdate FROM games WHERE published=1 AND startDate>today-2 so I can include in the actions list, when a new game has been published. When I run the query as I've got it written, I get all the actionids, and their gameids, but I don't get a row which shows the gameid when it was published. I understand that it may be possible that I need to run two seperate queries, and then somehow merge the results afterword with php, but I'm completely lost on where to start with that as well.

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  • What data structures and algorithms are applied within data warehouse cubes?

    - by Jeff Meatball Yang
    I understand that cubes are optimized data structures for aggregating and "slicing" large amounts of data. I just don't know how they are implemented. I can imagine a lot of this technology is proprietary, but are there any resources that I could use to start implementing my own cube technology? Set theory and lots of math are probably involved (and welcome as suggestions!), but I'm primarily interested in implementations: the data structures and query algorithms. Thanks!

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  • To log in stored procedures?

    - by hgulyan
    If you have a long running SP, do you log somehow it's actions or just wait for this message? "Command(s) completed successfully." I assume, that there can be plenty solutions on this subject, but is there any best practice - a simple solution that is frequently used?

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  • How to efficiently SELECT rows from database table based on selected set of values

    - by Chau Chee Yang
    I have a transaction table of 1 million rows. The table has a field name "Code" to keep customer's ID. There are about 10,000 different customer code. I have an GUI interface allow user to render a report from transaction table. User may select arbitrary number of customers for rendering. I use IN operator first and it works for few customers: SELECT * FROM TRANS_TABLE WHERE CODE IN ('...', '...', '...') I quickly run into problem if I select few thousand customers. There is limitation using IN operator. An alternate way is create a temporary table with only one field of CODE, and inject selected customer codes into the temporary table using INSERT statement. I may then using SELECT A.* FROM TRANS_TABLE A INNER JOIN TEMP B ON (A.CODE=B.CODE) This works nice for huge selection. However, there is performance overhead for temporary table creation, INSERT injection and dropping of temporary table. Do you aware of better solution to handle this situation?

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  • Insert Data from to a table

    - by Lee_McIntosh
    I have a table that lists number of comments from a particular site like the following: Date Site Comments Total --------------------------------------------------------------- 2010-04-01 00:00:00.000 1 5 5 2010-04-01 00:00:00.000 2 8 13 2010-04-01 00:00:00.000 4 2 7 2010-04-01 00:00:00.000 7 13 13 2010-04-01 00:00:00.000 9 1 2 I have another table that lists ALL sites for example from 1 to 10 Site ----- 1 2 ... 9 10 Using the following code i can find out which sites are missing entries for the previous month: SELECT s.site from tbl_Sites s EXCEPT SELECT c.site from tbl_Comments c WHERE c.[Date] = DATEADD(mm, DATEDIFF(mm, 0, GetDate()) -1,0) Producing: site ----- 3 5 6 8 10 I would like to be able to insert the missing sites that is listed from my query into the comments table with some default values, i.e '0's Date Site Comments Total --------------------------------------------------------------- 2010-04-01 00:00:00.000 3 0 0 2010-04-01 00:00:00.000 5 0 0 2010-04-01 00:00:00.000 6 0 0 2010-04-01 00:00:00.000 8 0 0 2010-04-01 00:00:00.000 10 0 0 the question is, how did i update/insert the table/values? cheers, Lee

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  • ISBNdb Retrieving and Managing Info

    - by Pierre Sylvestre
    Given a set of databases how can one you get information on a book with given price first (which consist of the average of a hidden list of prices coming from different web site) and followed by an optional second option that shows the list of the different web site with their page? To take an example given a query for ISBN 9785554443331 - it returns "Chemistry the central science 11 edition" : new:$50 used good condition:$35 used poor condition:$20 If the return does not match with our product list an option to "click here to visit our partner" appears and which returns: Atextbook: $10 Btextbook: $10 Ctextbook: $9 Dtextbook: $8.50 I understand that the first search would be done simultaneous on the web and our database to determine whether or not we have the book and the web to get the average of the price of a given list of web site. Thank you in advance for the help

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