Search Results

Search found 40744 results on 1630 pages for 'sql interview questions a'.

Page 625/1630 | < Previous Page | 621 622 623 624 625 626 627 628 629 630 631 632  | Next Page >

  • Assign table values to multiple variables using a single SELECT statement and CASE?

    - by Darth Continent
    I'm trying to assign values contained in a lookup table to multiple variables by using a single SELECT having multiple CASE statements. The table is a lookup table with two columns like so: [GreekAlphabetastic] SystemID Descriptor -------- ---------- 1 Alpha 2 Beta 3 Epsilon This is my syntax: SELECT @VariableTheFirst = CASE WHEN myField = 'Alpha' THEN tbl.SystemID END, @VariableTheSecond = CASE WHEN myField = 'Beta' THEN tbl.SystemID END, @VariableTheThird = CASE WHEN myField = 'Epsilon' THEN tbl.SystemID END FROM GreekAlphabetastic tbl However, when I check the variables after this statement executes, I expected each to be assigned the appropriate value, but instead only the last has a value assigned. SELECT @VariableTheFirst AS First, @VariableTheSecond AS Second, @VariableTheThird AS Third Results: First Second Third NULL NULL 3 What am I doing wrong?

    Read the article

  • Atomic INSERT/SELECT in HSQLDB

    - by PartlyCloudy
    Hello, I have the following hsqldb table, in which I map UUIDs to auto incremented IDs: SHORT_ID (BIG INT, PK, auto incremented) | UUID (VARCHAR, unique) Create command: CREATE TABLE table (SHORT_ID BIGINT GENERATED BY DEFAULT AS IDENTITY PRIMARY KEY, UUID VARCHAR(36) UNIQUE) In order to add new pairs concurrently, I want to use the atomic MERGE INTO statement. So my (prepared) statement looks like this: MERGE INTO table USING (VALUES(CAST(? AS VARCHAR(36)))) AS v(x) ON ID_MAP.UUID = v.x WHEN NOT MATCHED THEN INSERT VALUES v.x When I execute the statement (setting the placeholder correctly), I always get a Caused by: org.hsqldb.HsqlException: row column count mismatch Could you please give me a hint, what is going wrong here? Thanks in advance.

    Read the article

  • TSQL Query: Escaping Special Characters

    - by Abs
    Hello all, I am trying to escape special characters in a TSQL query. I have done this before: SELECT columns FROM table WHERE column LIKE '%\%%' ESCAPE '\' And it has worked. Now I have tried to do this now: UPDATE match SET rule_name='31' ESCAPE '\' But it has failed. I know none of the vlaues have a \ but it should still work. I am guessing its because it needs a LIKE statement but how else can I escape characters that I am adding to a database? In addition, does anyone have a link to all the special characters that should be escaped, I couldn't find any documentation on this! Thanks all for any help

    Read the article

  • Get most left|right|top|bottom point contained in box

    - by skyman
    I'm storing Points Of Interest (POI) in PostgreSQL database, and retrieve them via PHP script to Android application. To reduce internet usage I want my mobile app to know if there are any points in the neighborhood of currently displayed area. My idea is to store bounds of the rectangle containing all points already retrieved (in other words: nearest point on the left (West) of most west already retrieved, nearest point above (North) of most north already retrieved etc.) and I will make next query when any edge of screen goes outside of this bounds. Currently I can retrieve points which are in "single screen" (in the area covered by currently displayed map) using: SELECT * FROM ch WHERE loc <@ (box '((".-$latSpan.", ".$lonSpan."),(".$latSpan.", ".-$lonSpan."))' + point '".$loc."') Now I need to know four most remote points in each direction, than I will be able to retrieve next four "more remote" points. Is there any possibility to get those points (or box) directly from PostgreSQL (maybe using some "aggregate points to box" function)?

    Read the article

  • LINQ error when deployed - Security Exception - cannot create DataContext

    - by aximili
    The code below works locally, but when I deploy it to the server it gives the following error. Security Exception Description: The application attempted to perform an operation not allowed by the security policy. To grant this application the required permission please contact your system administrator or change the application's trust level in the configuration file. Exception Details: System.Security.SecurityException: Request for the permission of type 'System.Security.Permissions.FileIOPermission, mscorlib, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089' failed. The code is protected void Page_Load(object sender, EventArgs e) { DataContext context = new DataContext(Global.ConnectionString); // <-- throws the exception //Table<Group> _kindergartensTable = context.GetTable<Group>(); Response.Write("ok"); } I have set full write permissons on all files and folders on the server. Any suggestions how to solve this problem? Thanks in advance.

    Read the article

  • How to avoid using duplicate savepoint names in nested transactions in nested stored procs?

    - by Gary McGill
    I have a pattern that I almost always follow, where if I need to wrap up an operation in a transaction, I do this: BEGIN TRANSACTION SAVE TRANSACTION TX -- Stuff IF @error <> 0 ROLLBACK TRANSACTION TX COMMIT TRANSACTION That's served me well enough in the past, but after years of using this pattern (and copy-pasting the above code), I've suddenly discovered a flaw which comes as a complete shock. Quite often, I'll have a stored procedure calling other stored procedures, all of which use this same pattern. What I've discovered (to my cost) is that because I'm using the same savepoint name everywhere, I can get into a situation where my outer transaction is partially committed - precisely the opposite of the atomicity that I'm trying to achieve. I've put together an example that exhibits the problem. This is a single batch (no nested stored procs), and so it looks a little odd in that you probably wouldn't use the same savepoint name twice in the same batch, but my real-world scenario would be too confusing to post. CREATE TABLE Test (test INTEGER NOT NULL) BEGIN TRAN SAVE TRAN TX BEGIN TRAN SAVE TRAN TX INSERT INTO Test(test) VALUES (1) COMMIT TRAN TX BEGIN TRAN SAVE TRAN TX INSERT INTO Test(test) VALUES (2) COMMIT TRAN TX DELETE FROM Test ROLLBACK TRAN TX COMMIT TRAN TX SELECT * FROM Test DROP TABLE Test When I execute this, it lists one record, with value "1". In other words, even though I rolled back my outer transaction, a record was added to the table. What's happening is that the ROLLBACK TRANSACTION TX at the outer level is rolling back as far as the last SAVE TRANSACTION TX at the inner level. Now that I write this all out, I can see the logic behind it: the server is looking back through the log file, treating it as a linear stream of transactions; it doesn't understand the nesting/hierarchy implied by either the nesting of the transactions (or, in my real-world scenario, by the calls to other stored procedures). So, clearly, I need to start using unique savepoint names instead of blindly using "TX" everywhere. But - and this is where I finally get to the point - is there a way to do this in a copy-pastable way so that I can still use the same code everywhere? Can I auto-generate the savepoint name on the fly somehow? Is there a convention or best-practice for doing this sort of thing? It's not exactly hard to come up with a unique name every time you start a transaction (could base it off the SP name, or somesuch), but I do worry that eventually there would be a conflict - and you wouldn't know about it because rather than causing an error it just silently destroys your data... :-(

    Read the article

  • Multiple Columns as Primary keys

    - by rockbala
    CREATE TABLE Persons ( P_Id int NOT NULL, LastName varchar(255) NOT NULL, FirstName varchar(255), Address varchar(255), City varchar(255), CONSTRAINT pk_PersonID PRIMARY KEY (P_Id,LastName) ) The above example is taken from w3schools. From the above example, my understanding is that both P_Id, LastName together represents a Primary Key for the table Persons, correct ? Another question is why would some one want to use multiple columns as Primary keys instead of a single column ? How many such columns can be used in together as Primary key in a given table ? Thanks Balaji S

    Read the article

  • Calculate Percentage help ORACLE L@@K

    - by DAVID
    Hi this code gives me employee salaries and manager salaries. SELECT E.EMP_FNAME AS MANAGER, E.EMP_SALARY, D.DEPT_NO, A.EMP_FNAME AS EMPLOYEE, A.EMP_SALARY FROM EMPLOYEE E, EMPLOYEE A, DEPARTMENT D WHERE E.EMP_NIN = A.EMP_MANAGER AND A.EMP_MANAGER = D.EMP_MANAGER; How can i only show the employees that have a salary within 10% of their manager salary?

    Read the article

  • Problem with write query

    - by phenevo
    Hi, I've got collection of geo objects in database: There are four Tables: Countries Regions Provinces Cities Cities has inter alia ProvinceCode Provinces has inter alia regionCode Regions has inter alia CountryCode And there is fifth Table: Descriptions ObjectCode ObjectType(country, region, province, city) Description. How to get from Descriptions table, all descriptions from objects which are in the definite country ??

    Read the article

  • How to optimize this MySQL query

    - by James Simpson
    This query was working fine when the database was small, but now that there are millions of rows in the database, I am realizing I should have looked at optimizing this earlier. It is looking at over 600,000 rows and is Using where; Using temporary; Using filesort (which leads to an execution time of 5-10 seconds). It is using an index on the field 'battle_type.' SELECT username, SUM( outcome ) AS wins, COUNT( * ) - SUM( outcome ) AS losses FROM tblBattleHistory WHERE battle_type = '0' && outcome < '2' GROUP BY username ORDER BY wins DESC , losses ASC , username ASC LIMIT 0 , 50

    Read the article

  • Best approach for authorisation rules

    - by Maciej
    I'm wonder about best approach of implementation auth. rules in Client-Server app using Business Objects. I've noticed common tactic is: - on DB side: implement one role for application, used for all app's users - definition users right and roles and assign users to proper group - Client side: add to Business Object's getters/setters rights checker allowing write / display data for particular user My concern is if this is really good approach from security perspective. It looks DB sends all information to Client, and then client's logic decide what to display or not. So, potentially advanced user can make query from their box and see/change anything. Isn't it?

    Read the article

  • SOAP call with query on result (SSRS, Sharepoint)

    - by Erik404
    Hi! I created a report in VS using a shared data source which is connected to a sharepoint list. In the report I created a dataset with a SOAP call to the data source so I get the result from the sharepoint list in a table. this is the soap call <Query> <SoapAction>http://schemas.microsoft.com/sharepoint/soap/GetListItems</SoapAction> <Method Namespace="http://schemas.microsoft.com/sharepoint/soap/" Name="GetListItems"> <Parameters> <Parameter Name="listName"> <DefaultValue>{BD8D39B7-FA0B-491D-AC6F-EC9B0978E0CE}</DefaultValue> </Parameter> <Parameter Name="viewName"> <DefaultValue>{E2168426-804F-4836-9BE4-DC5F8D08A54F}</DefaultValue> </Parameter> <Parameter Name="rowLimit"> <DefaultValue>9999</DefaultValue> </Parameter> </Parameters> </Method> <ElementPath IgnoreNamespaces="True">*</ElementPath> </Query> THis works fine, I have a result which I can show in a report, but I want to have the ability to select a parameter to filter the result on. I have created a parameter and when I preview the Report I see the dropdownbox which I can use to make a selection from the Title field, when I do this it still shows the first record, obviously it doens't work yet (DUH!) because I need to create a query somewhere, But! I have no idea where, I tried to include <Where> <Eq> <FieldRef Name="ows_Title" /> <Value Type="Text">testValue</Value> </Eq> </Where> in the the soap request but it didn't worked... I've searched teh intarwebz but couldn't find any simliar problems... kinda stuck now...any thoughts on this? EDIT Here's the query I used according to the blogpost Alex Angas linked. <Query> <SoapAction>http://schemas.microsoft.com/sharepoint/soap/GetListItems</SoapAction> <Method Namespace="http://schemas.microsoft.com/sharepoint/soap/" Name="GetListItems"> <queryOptions></queryOptions> <query><Query> <Where> <Eq> <FieldRef Name="ows_Title"/> <Value Type="Text">someValue</Value> </Eq> </Where> </Query></query> <Parameters> <Parameter Name="listName"> <DefaultValue>{BD8D39B7-FA0B-491D-AC6F-EC9B0978E0CE}</DefaultValue> </Parameter> <Parameter Name="viewName"> <DefaultValue>{E2168426-804F-4836-9BE4-DC5F8D08A54F}</DefaultValue> </Parameter> <Parameter Name="rowLimit"> <DefaultValue>9999</DefaultValue> </Parameter> </Parameters> </Method> <ElementPath IgnoreNamespaces="True">*</ElementPath> </Query> I tried to put the new query statement in every possible way in the existing, but it doesn't work at all, I do not get an error though so the code is valid, but I still get an unfiltered list as return... pulling my hair out here!

    Read the article

  • Primary Key Identity Value Increments On Unique Key Constraint Violation

    - by Jed
    I have a SqlServer 2008 table which has a Primary Key (IsIdentity=Yes) and three other fields that make up a Unique Key constraint. In addition I have a store procedure that inserts a record into the table and I call the sproc via C# using a SqlConnection object. The C# sproc call works fine, however I have noticed interesting results when the C# sproc call violates the Unique Key constraint.... When the sproc call violates the Unique Key constraint, a SqlException is thrown - which is no surprise and cool. However, I notice that the next record that is successfully added to the table has a PK value that is not exactly one more than the previous record - For example: Say the table has five records where the PK values are 1,2,3,4, and 5. The sproc attempts to insert a sixth record, but the Unique Key constraint is violated and, so, the sixth record is not inserted. Then the sproc attempts to insert another record and this time it is successful. - This new record is given a PK value of 7 instead of 6. Is this normal behavior? If so, can you give me a reason why this is so? (If a record fails to insert, why is the PK index incremented?) If this is not normal behavior, can you give me any hints as to why I am seeing these symptoms?

    Read the article

  • How to get identities of inserted data records using SQL bulk copy

    - by Olga
    Hello I have a ADO.NET dataTable with about 100.000 records. In this table there is a column "xyID" which has no values in it, because they are generated by insertion into my MSSQL Database. Now i have the problem, that i need this IDs for other processes. I am looking for a way to bulk copy this dataTable into the MSSQL database, and within the same "step" to "fill" my dataTable with the generated IDs. Thank you for your answers!

    Read the article

  • SQL Server, temporary tables with truncate vs table variable with delete

    - by Richard
    I have a stored procedure inside which I create a temporary table that typically contains between 1 and 10 rows. This table is truncated and filled many times during the stored procedure. It is truncated as this is faster than delete. Do I get any performance increase by replacing this temporary table with a table variable when I suffer a penalty for using delete (truncate does not work on table variables) Whilst table variables are mainly in memory and are generally faster than temp tables do I loose any benefit by having to delete rather than truncate?

    Read the article

  • MissingMethodException ( Can`t find PInvoke DLL 'sqlceme30.dll ' ) for Windows Mobile

    - by anyinfonet
    Hello. I have developed a win mobile (v5.0) application and I use ONLY 1 database SQLITE with these references: System.Data.SQLite.dll (assembly version & product version : 1.0.65.0); SQLite.Interop.065.DLL (product version : 1.0 and is a c++ lib for first dll ). After 5 weeks of using of this application, I get today a weird exception and I dont understand what it is? Exception is: MissingMethodException Can`t find PInvoke DLL 'sqlceme30.dll ' at System.Data.SqlServerCe.SqlCeCommand.ReleaseNativeInterfaces() at System.Data.SqlServerCe.SqlCeCommand.Dispose(Boolean disposing) ...... What`s wrong? Anyone know about this to explain me please? By the way : until now I delevoped 3-4 applications (1 year ago )using these references and everything worked fine.

    Read the article

  • SSIS - Wizard vs manual vs programming

    - by alchemical
    I'd like to move 26 tables from one DB to another. I see I can do this in the SSIS Import and Export Wizard. I believe the other approach would be to select tools from the toolbar in Data Flow and then configure them all. When is it better to use the wizard and when is it best to create the package manually (with the visual tools) or programmatically? One thing I noticed with the Wizard is that it lets me select multiple tables at once, but I could not find a way to get back to that screen once the package is created, so that I could edit the various tables all in one place.

    Read the article

  • Mysql Sub Select Query Optimization

    - by Matt
    I'm running a query daily to compile stats - but it seems really inefficient. This is the Query: SELECT a.id, tstamp, label_id, (SELECT author_id FROM b WHERE b.tid = a.id ORDER BY b.tstamp DESC LIMIT 1) AS author_id FROM a, b WHERE (status = '2' OR status = '3') AND category != 6 AND a.id = b.tid AND (b.type = 'C' OR b.type = 'R') AND a.tstamp1 BETWEEN {$timestamp_start} AND {$timestamp_end} ORDER BY b.tstamp DESC LIMIT 500 This query seems to run really slow. Apologies for the crap naming - I've been asked to not reveal the actual table names. The reason there is a sub select is because the outer select gets one row from the table a and it gets a row from table b. But also need to know the latest author_id from table b as well, so I run a subselect to return that one. I don't want to run another select inside a php loop - as that is also inefficient. It works correctly - I just need to find a much faster way of getting this data set.

    Read the article

  • SQLServer:Namespaces preventing access to query data

    - by Brian
    Hi A beginners question, hopefully easily answered. I've got an xml file I want to load into SQLServer 2008 and extract the useful informaiton. I'm starting simple and just trying to extract the name (\gpx\name). The code I have is: DECLARE @x xml; SELECT @x = xCol.BulkColumn FROM OPENROWSET (BULK 'C:\Data\EM.gpx', SINGLE_BLOB) AS xCol; -- confirm the xml data is in @x select @x as XML_Data -- try and get the name of the gpx section SELECT c.value('name[1]', 'varchar(200)') as Name from @x.nodes('gpx') x(c) Below is a heavily shortened version of the xml file: <?xml version="1.0" encoding="utf-8"?> <gpx xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" version="1.0" creator="Groundspeak Pocket Query" xsi:schemaLocation="http://www.topografix.com/GPX/1/0 http://www.topografix.com/GPX/1/0/gpx.xsd http://www.groundspeak.com/cache/1/0 http://www.groundspeak.com/cache/1/0/cache.xsd" xmlns="http://www.topografix.com/GPX/1/0"> <name>EM</name> <desc>Geocache file generated by Groundspeak</desc> <author>Groundspeak</author> <email>[email protected]</email> <time>2010-03-24T14:01:36.4931342Z</time> <keywords>cache, geocache, groundspeak</keywords> <wpt lat="51.2586" lon="-2.213067"> <time>2008-03-30T07:00:00Z</time> <name>GC1APHM</name> <desc>Sandman's Noble Hoard by Sandman1973, Unknown Cache (2/3)</desc> <groundspeak:cache id="832000" available="True" archived="False" xmlns:groundspeak="http://www.groundspeak.com/cache/1/0"> <groundspeak:name>Sandman's Noble Hoard</groundspeak:name> <groundspeak:placed_by>Sandman1973</groundspeak:placed_by> </groundspeak:cache> </wpt> </gpx> If the first two lines are replaced with just: <gpx> the above example works correctly, however I then can't access groundspeak:name (/gpx/wpt/groundspeak:cache/groundspeak:name), so my guess its a problem with the namespace. Any help would be appriciated.

    Read the article

< Previous Page | 621 622 623 624 625 626 627 628 629 630 631 632  | Next Page >