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  • How to 'insert if not exists' in MySQL?

    - by warren
    I started by googling, and found this article which talks about mutex tables. I have a table with ~14 million records. If I want to add more data in the same format, is there a way to ensure the record I want to insert does not already exist without using a pair of queries (ie, one query to check and one to insert is the result set is empty)? Does a unique constraint on a field guarantee the insert will fail if it's already there? It seems that with merely a constraint, when I issue the insert via php, the script croaks.

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  • Are application servers necessary? Advantages of using one? (And other JEE questions)

    - by Mike
    Apologies for the long question.. there seems to be other similar questions on here but none really clear up my confusion. I'd be really grateful if someone could confirm or correct my understanding: Java Enterprise Edition is a set of APIs for building enterprise applications, which take away the burden of developing parts of the system that aren't actually features of the application you are trying to build (i.e. messaging, transactions etc). To do this, you can use an application server, which implements these APIs. So you could use JBoss, Glassfish, WebSphere, WebLogic etc which would provide your application with these enterprise services. However, there are many other implementations of these individual services available such as ActiveMQ for messaging, Hibernate for persistence, OpenEJB etc. You can download these implementations as Java libraries and include them in your application, and use the services they provide in a similar way to using the services provided by an application server. So if my understanding is correct, my questions are: I've read a lot of places that application servers are necessary for JEE features like EJB, but can't you just use an implementation such as OpenEJB and not need an application server at all? Are there any features that an application server provides which you cannot get from another source? Why would/wouldn't I choose an application server over a custom stack such as Tomcat, OpenEJB, ActiveMQ, and Hibernate? Is Spring a complete alternative to JEE? Does it ever require an application server or always just a servlet container? Why would someone choose Spring over JEE? Any help would be much appreciated!

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  • In mysql, is "explain ..." always safe?

    - by tye
    If I allow a group of users to submit "explain $whatever" to mysql (via Perl's DBI using DBD::mysql), is there anything that a user could put into $whatever that would make any database changes, leak non-trivial information, or even cause significant database load? If so, how? I know that via "explain $whatever" one can figure out what tables / columns exist (you have to guess names, though) and roughly how many records are in a table or how many records have a particular value for an indexed field. I don't expect one to be able to get any information about the contents of unindexed fields. DBD::mysql should not allow multiple statements so I don't expect it to be possible to run any query (just explain one query). Even subqueries should not be executed, just explained. But I'm not a mysql expert and there are surely features of mysql that I'm not even aware of. In trying to come up with a query plan, might the optimizer actual execute an expression in order to come up with the value that an indexed field is going to be compared against? explain select * from atable where class = somefunction(...) where atable.class is indexed and not unique and class='unused' would find no records but class='common' would find a million records. Might 'explain' evaluate somefunction(...)? And then could somefunction(...) be written such that it modifies data?

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  • Disable animations when ending search in iPhone

    - by camilo
    Hi. A quicky: is there a way to dismiss the keyboard and the searchDisplayController without animation? I was able to do it when the user presses "Cancel", but when the user presses the black "window thingy" above search field (only visible while the user hasn't inserted any text), the animation always occurs, even when I change the delegate functions. Is there a way to control this, or as an alternative, to disable the user to end searching by pressing the black window? Thanks in advance.

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  • MySQL Insert Data Question

    - by Nano HE
    Hi, assume I already created a table in MySQL as below CREATE TABLE IF NOT EXISTS `sales` ( `id` smallint(5) unsigned NOT NULL auto_increment, `client_id` smallint(5) unsigned NOT NULL, `order_time` timestamp NOT NULL default CURRENT_TIMESTAMP on update CURRENT_TIMESTAMP, `sub_total` decimal(8,2) NOT NULL, `shipping_cost` decimal(8,2) NOT NULL, `total_cost` decimal(8,2) NOT NULL, PRIMARY KEY (`id`) ) ENGINE=MyISAM DEFAULT CHARSET=latin1 AUTO_INCREMENT=9 ; -- -- Dumping data for table `sales` -- If I added a new field must_fill for the current table. `must_fill` tinyint(1) unsigned NOT NULL, User can insert less than the number of fiels items to the table defaultly, just as the script of below. INSERT INTO `sales` (`id`, `client_id`, `order_time`, `sub_total`, `shipping_cost`, `total_cost`) VALUES (8, 12312, '2007-12-19 01:30:45', 10.75, 3.00, 13.75); It's fine. But How can I configure the field (must_fill) to a MUST INCLUDE Data field when user plan to insert into new data. BTW, The code will be integrated in PHP script.

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  • Simple ASP function question

    - by J Harley
    Good Morning, I have got the following function: FUNCTION queryDatabaseCount(sqlStr) SET queryDatabaseCountRecordSet = databaseConnection.Execute(sqlStr) If queryDatabaseCountRecordSet.EOF Then queryDatabaseCountRecordSet.Close queryDatabaseCount = 0 Else QueryArray = queryDatabaseCountRecordSet.GetRows queryDatabaseCountRecordSet.Close queryDatabaseCount = UBound(QueryArray,2) + 1 End If END FUNCTION And the following dbConnect: SET databaseConnection = Server.CreateObject("ADODB.Connection") databaseConnection.Open "Provider=SQLOLEDB; Data Source ="&dataSource&"; Initial Catalog ="&initialCatalog&"; User Id ="&userID&"; Password="&password&"" But for some reason I get the following error: ADODB.Recordset error '800a0e78' Operation is not allowed when the object is closed. /UBS/DBMS/includes/blocks/block_databaseoverview.asp, line 30 Does anyone have any suggestions? Many Thanks, Joel

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  • Why am I unable to create a trigger using my SqlCommand?

    - by acidzombie24
    The line cmd.ExecuteNonQuery(); cmd.CommandText CREATE TRIGGER subscription_trig_0 ON subscription AFTER INSERT AS UPDATE user_data SET msg_count=msg_count+1 FROM user_data JOIN INSERTED ON user_data.id = INSERTED.recipient; The exception: Incorrect syntax near the keyword 'TRIGGER'. Then using VS 2010, connected to the very same file (a mdf file) I run the query above and I get a success message. WTF!

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  • Loop Stored Procedure in VB.Net (win form)

    - by Mo
    Hello, I am trying to run a for loop for a backup system and inside that i want to run a SP that will loop. Below is the code that does not work for me.. Any ideas please? Dim TotalTables As Integer Dim i As Integer TotalTables = 10 For i = 1 To TotalTables objDL.BackupTables(220, i, 001) ' (This is a method from the DL and the 3 parameters are integars) Next I tried the SP and it works perfectly in SQLServer

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  • mysql count rows and grop them by month

    - by user2661296
    I have a table called cc_calls and there I have many call records I want to count them and group them in months I have a timestamp called starttime and I can use that row to extract the month, also limit the count for 12 months the results should be like: Month Count January 768768 February 876786 March 987979 April 765765 May 898797 June 876876 July 786575 August 765765 September 689787 October 765879 November 897989 December 876876 Can anyone guide me or show me the mysql query that I need to get this result.

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  • How to retrieve last primary Id from mdb's table?

    - by William
    I got table with next columns: Id, Name, Age, Class I am trying to insert new row in db like this: INSERT INTO MyTable (Name, Age, Class) VALUES (@name, @age, @class) And get an exeption: "Index or primary key cannot contain a Null value." The question is how to add a new row without knowing next primary Id, or maybe there is a way to get this Id from the table with the help of another query ?

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  • I got an error when implementing tde in sql2008

    - by mahima
    while using USE mssqltips_tde; CREATE DATABASE ENCRYPTION KEY with ALGORITHM = AES_256 ENCRYPTION BY SERVER CERTIFICATE TDECert GO getting error Msg 156, Level 15, State 1, Line 2 Incorrect syntax near the keyword 'KEY'. Msg 319, Level 15, State 1, Line 3 Incorrect syntax near the keyword 'with'. If this statement is a common table expression or an xmlnamespaces clause, the previous statement must be terminated with a semicolon. please help in resolving the same as i need to implement Encryption on my DB

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  • alter mysqldump file before import

    - by julio
    Hi-- I have a mysqldump file created from an earlier version of a product that can't be imported into a new version of the product, since the db structure has changed slightly (mainly altering a column that was NOT NULL DEFAULT 0 to UNIQUE KEY DEFAULT NULL). If I just import the old dump file, it will error out since the column that has default values of 0 now breaks the UNIQUE constraint. It would be easy enough to either manually alter the mysqldump file, or import into a temp table and change it, then copy to the new table. However, is there a way to do this programatically, so it will be repeatable and not manual? (this will need to happen for many instances of this product). I'm thinking something like disabling key constraints for the import, then setting all values that = 0 to NULL, then re-enabling the key constraints? Is this possible? Any help appreciated.

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  • What are the rules governing how a bind variable can be used in Postgres and where is this defined?

    - by Craig Miles
    I can have a table and function defined as: CREATE TABLE mytable ( mycol integer ); INSERT INTO mytable VALUES (1); CREATE OR REPLACE FUNCTION myfunction (l_myvar integer) RETURNS mytable AS $$ DECLARE l_myrow mytable; BEGIN SELECT * INTO l_myrow FROM mytable WHERE mycol = l_myvar; RETURN l_myrow; END; $$ LANGUAGE plpgsql; In this case l_myvar acts as a bind variable for the value passed when I call: SELECT * FROM myfunction(1); and returns the row where mycol = 1 If I redefine the function as: CREATE OR REPLACE FUNCTION myfunction (l_myvar integer) RETURNS mytable AS $$ DECLARE l_myrow mytable; BEGIN SELECT * INTO l_myrow FROM mytable WHERE mycol IN (l_myvar); RETURN l_myrow; END; $$ LANGUAGE plpgsql; SELECT * FROM myfunction(1); still returns the row where mycol = 1 However, if I now change the function definition to allow me to pass an integer array and try to this array in the IN clause, I get an error: CREATE OR REPLACE FUNCTION myfunction (l_myvar integer[]) RETURNS mytable AS $$ DECLARE l_myrow mytable; BEGIN SELECT * INTO l_myrow FROM mytable WHERE mycol IN (array_to_string(l_myvar, ',')); RETURN l_myrow; END; $$ LANGUAGE plpgsql; Analysis reveals that although: SELECT array_to_string(ARRAY[1, 2], ','); returns 1,2 as expected SELECT * FROM myfunction(ARRAY[1, 2]); returns the error operator does not exist: integer = text at the line: WHERE mycol IN (array_to_string(l_myvar, ',')); If I execute: SELECT * FROM mytable WHERE mycol IN (1,2); I get the expected result. Given that array_to_string(l_myvar, ',') evaluates to 1,2 as shown, why arent these statements equivalent. From the error message it is something to do with datatypes, but doesnt the IN(variable) construct appear to be behaving differently from the = variable construct? What are the rules here? I know that I could build a statement to EXECUTE, treating everything as a string, to achieve what I want to do, so I am not looking for that as a solution. I do want to understand though what is going on in this example. Is there a modification to this approach to make it work, the particular example being to pass in an array of values to build a dynamic IN clause without resorting to EXECUTE? Thanks in advance Craig

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  • How to return table name from stored procedure in dataset.

    - by Shantanu Gupta
    I used a dataset to store 15 tables that I need at the time of loading. When i filled all the tables using stored procedure it returns me all the table but name of the table doesn't comes as that of actual table name in a database. It takes all the table with table name as Table1, Table2, Table3... I want them to be with the name as they actually are in table. SELECT PK_GUEST_TYPE, [DESCRIPTION] FROM L_GUEST_TYPE SELECT PK_AGE_GROUP_ID, AGE_GROUP FROM L_AGE_GROUP SELECT PK_COMPANY_ID, COMPANY_NAME FROM M_COMPANY SELECT PK_COUNTRY_ID, COUNTRY FROM L_COUNTRY SELECT PK_EYE_COLOR_ID, [DESCRIPTION] FROM L_EYE_COLOR SELECT PK_GENDER_ID, [DESCRIPTION] FROM L_GENDER SELECT PK_HAIR_COLOR_ID, [DESCRIPTION] FROM L_HAIR_COLOR SELECT PK_STATE_PROVONCE_ID, [DESCRIPTION] FROM L_STATE_PROVINCE SELECT PK_STATUS_ID, [DESCRIPTION] FROM L_STATUS SELECT PK_TITLE_ID, [DESCRIPTION] FROM L_TITLE SELECT PK_TOWER_ID, [DESCRIPTION] FROM M_TOWER SELECT PK_CITY_ID, [DESCRIPTION] FROM L_CITY SELECT PK_REGISTER_TYPE_ID, [DESCRIPTION] FROM L_REGISTER_TYPE Here is my frontend coding to fill dataset. OpenConnection(); adp.Fill(ds); CloseConnection(true);

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  • How do I select and group by a portion of a string?

    - by Russ Bradberry
    Given I have data like the following, how can I select and group by portions of a string? Version Users 1.1.1 1 1.1.23 3 1.1.45 1 2.1.24 3 2.1.12 1 2.1.45 3 3.1.10 1 3.1.23 3 What I want is to sum up the users using version 1.1.x and 2.2.x and 3.3.x etc, but I'm not sure how I can group on a partial string in a select statement. edit What the data should return like is this: Version Users 1.1.XX 5 2.1.XX 7 3.1.XX 4 There is an infinite variable number of versions, some are in this format (major, minor, build) some are just major, minor and some are just major, the only time I want to "roll up" the versions is when there is a build.

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  • How to use database to generate multiple folder content page?

    - by VenomVipes
    Scenario :I am trying to build a Mobile Entertainment Portal. It will enable users to download Music & Movies to their Cell Phones... Problem Exp : Suppose I upload 100 folders of Songs, each folder is for one Album. I want a way to generate a page with all the folders name (Album Name) in it. If user click on the page, they should be taken to a page where they get list of all songs in the album. Clicking on any song name will let them download it. Can it be done anyway or will I have to manually design each of the 3 pages for each album. If I do that, its time consuming and also will be difficult to change anything like footer, header...

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  • Listing issue, GROUP mysql

    - by SethCodes
    Here is a mock-up example of Mysql table: | ID | Country | City | ________________________________ | 1 | Sweden | Stockholm | | 2 | Sweden | Stockholm | | 3 | Sweden | Lund | | 4 | Sweden | Lund | | 5 | Germany | Berlin | | 6 | Germany | Berlin | | 7 | Germany | Hamburg | | 8 | Germany | Hamburg | Notice how both rows Country and city have repeated values inside them. Using GROUP BY country, city in my PDO query, the values will not repeat while in loop. Here is PDO for this: $query = "SELECT id, city, country FROM table GROUP BY country, city"; $stmt = $db->query($query); while($row = $stmt->fetch(PDO::FETCH_ASSOC)) : The above code will result in an output like this (some editing in-between). GROUP BY works but the country repeats: Sweden - Stockholm Sweden - Lund Germany - Berlin Germany - Hamburg Using bootstrap collapse and above code, I separate the country from the city with a simple drop down collopase. Here is code: <li> <a data-toggle="collapse" data-target="#<?= $row['id']; ?>" href="search.php?country=<?= $row['country']; ?>"> <?= $row['country']; ?> </a> <div id ="<?= $row['id']; ?>" class="collapse in"> //collapse div here <a href="search.php?city=<?= $row['city']; ?>"> <?= $row['city']; ?><br></a> </div> //end </li> It then looks something like this (once collapse is initiated): Sweden > Stockholm Sweden > Lund Germany >Berlin Germany >Hamburg Here is where I face the problem. The above lists the values Sweden and Germany 2 times. I want Sweden and Germany to only list one time, and the cities listed below, so the desired look is to be this: Sweden // Lists one time > Stockholm > Lund Germany // Lists one time >Berlin >Hamburg I have tried using DISTINCT, GROUP_CONTACT and other methods, yet none get my desired output (above). Suggestions? Below is my current full code in action: <? $query = "SELECT id, city, country FROM table GROUP BY country, city"; $stmt = $db->query($query); while($row = $stmt->fetch(PDO::FETCH_ASSOC)) : ?> <li> <a data-toggle="collapse" data-target="#<?= $row['id']; ?>" href="search.php?country=<?= $row['country']; ?>"> <?= $row['country']; ?> </a> <div id ="<?= $row['id']; ?>" class="collapse in"> //collapse div here <a href="search.php?city=<?= $row['city']; ?>"> <?= $row['city']; ?><br></a> </div> //end </li> <? endwhile ?>

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  • Table for each region in MySQL

    - by King Wu
    There are four regions with more than one million records total. Should I create a table with a region column or a table for each region and combine them to get the top ranks? If I combine all four regions, none of my columns will be unique so I will need to also add an id column for my primary key. Otherwise, name, accountId & characterId would be candidate keys or should I just add an id column anyways. Table: ---------------------------------------------------------------- | name | accountId | iconId | level | characterId | updateDate | ----------------------------------------------------------------

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  • Adding relative week number column to MySQl results

    - by Anthony
    I have a table with 3 columns: user, value, and date. The main query returns the values for a specific user based on a date range: SELECT date, value FROM values WHERE user = '$user' AND date BETWEEN $start AND $end What I would like is for the results to also have a column indicating the week number relative to the date range. So if the date range is 1/1/2010 - 1/20/2010, then any results from the first Sun - Sat of that range are week 1, the next Sun - Sat are week 2, etc. If the date range starts on a Saturday, then only results from that one day would be week 1. If the date range starts on Thursday but the first result is on the following Monday, it would be week 2, and there are no week 1 results. Is this something fairly simple to add to the query? The only ideas I can come up with would be based on the week number for the year or the week number based on the results themselves (where in that second example above, the first result always gets week 1).

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  • Custom order in Oracle PL/SQL

    - by Jasim
    I have an oracle query in which and i want the result to be in custom order 'SENIOR DIRECTOR', 'DIRECTOR', 'MANAGER', 'EMPLOYEE' which is from the field GRADE_DESCRIPTON. I am using the below query. However I am not getting the desired result The order of the result im getting is 'SENIOR DIRECTOR','MANAGER', DIRECTOR,'EMPLOYEE' SELECT DISTINCT GRADE_DESCRIPTION, HIRING_FORECATS.* FROM GRADE_MASTER left join IRING_FORECATS ON (HIRING_FORECATS.GRADE = GRADE_MASTER.GRADE_DESCRIPTION and HIRING_FORECATS.LOCATION = 'HO' ) order by decode(GRADE_MASTER.GRADE_DESCRIPTION, 'SENIOR DIRECTOR', 'DIRECTOR', 'MANAGER', 'EMPLOYEE') Any Suggestions??

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  • association of more than one model to a listview

    - by Veer
    I have 3 Tables in my database. Each table has 3 fields each, excluding the ID field. out of which 2 fields are of type nvarchar. None of the tables are related. My ListView in the application helps the user to search my database, the search being incremental. The search includes the nvarchar fields of the 3 tables ie, 6 fields in total. Eg: PhoneBook: Name, PhoneNo Notes: Title, Content Bookmarks: Name, url I've the models generated for the 3 tables. Now the ListBox should display the Ph.Name, Title and the Bo.Name fields. ie, It should be bound to them. But they are from different models. I also should be able to perform CRUD operation on the item searched. How would i do that? P.S: Separate ViewModels are created for each Model which are used for their respective views for handling those tables individually. But this is an integrated view where the user should be able to search everything. Also please somebody suggest me a better Title for this question:)

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  • SQL query for an access database needed

    - by masfenix
    Hey guys, first off all sorry, i can't login using my yahoo provider. anyways I have this problem. Let me explain it to you, and then I'll show you a picture. I have a access db table. It has 'report id', 'recpient id', and 'recipient name' and 'report req'. What the table "means" is that do the user using that report still require it or can we decommission it. Here is how the data looks like (blocked out company userids and usernames): *check the link below, I cant post pictures cuz yahoo open id provider isnt working. So basically I need to have 3 select queries: 1) Select all the reports where for each report, ALL the users have said no to 'reportreq'. In plain English, i want a listing of all the reports that we have to decommission because no user wants it. 2) Select all the reports where the report is required, and the batchprintcopy is more then 0. This way we can see which report needs to be printed and save paper instead of printing all the reports. 3)A listing of all the reports where the reportreq field is empty. I think i can figure this one out myself. This is using Access/VBA and the data will be exported to an excel spreadsheet. I just a simple query if it exists, OR an alogorithm to do it quickly. I just tried making a "matrix" and it took about 2 hours to populate. https://docs.google.com/uc?id=0B2EMqbpeBpQkMTIyMzA5ZjMtMGQ3Zi00NzRmLWEyMDAtODcxYWM0ZTFmMDFk&hl=en_US

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  • MSSQL: Primary Key Schema Largely Guid but Sometimes Integer Types...

    - by Code Sherpa
    OK, this may be a silly question but... I have inherited a project and am tasked with going over the primary key relationships. The project largely uses Guids. I say "largely" because there are examples where tables use integral types to reflect enumerations. For example, dbo.MessageFolder has MessageFolderId of type int to reflect public emum MessageFolderTypes { inbox = 1, sent = 2, trash = 3, etc... } This happens a lot. There are tables with primary keys of type int which is unavoidable because of their reliance on enumerations and tables with primary keys of type Guid which reflect the primary key choice on the part of the previous programmer. Should I care that the PK schema is spotty like this? It doesn't feel right but does it really matter? If this could create a problem, how do I get around it (I really can't move all PKs to type int without serious legwork and I have never heard of enumerations that have guid values)? Thanks.

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