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SQL Server SELECT INTO @variable?

... You cannot SELECT .. INTO .. a TABLE VARIABLE. The best you can do is create it first, then insert into it. Your 2nd snippet has to be DECLARE @TempCustomer TABLE ( CustomerId uniqueidentifier, FirstName nvarchar(100), LastNa...
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MySQL: selecting rows where a column is null

I'm having a problem where when I try to select the rows that have a NULL for a certain column, it returns an empty set. However, when I look at the table in phpMyAdmin, it says null for most of the rows. ...
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Any way to select without causing locking in MySQL?

...s/22-mysql-with-nolock.aspx in MS SQL Server you would do the following: SELECT * FROM TABLE_NAME WITH (nolock) and the MYSQL equivalent is SET SESSION TRANSACTION ISOLATION LEVEL READ UNCOMMITTED ; SELECT * FROM TABLE_NAME ; SET SESSION TRANSACTION ISOLATION LEVEL REPEATABLE READ ; EDIT Mic...
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SQL “select where not in subquery” returns no results

...MySQL There are three ways to do such a query: LEFT JOIN / IS NULL: SELECT * FROM common LEFT JOIN table1 t1 ON t1.common_id = common.common_id WHERE t1.common_id IS NULL NOT EXISTS: SELECT * FROM common WHERE NOT EXISTS ( SELECT NULL FROM ...
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Can you have if-then-else logic in SQL? [duplicate]

I need to do select data from a table based on some kind of priority like so: 7 Answers ...
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How to select from subquery using Laravel Query Builder?

... Note that if you have a complex query as a belongsToMany as subselect you have to add getQuery() twice => $sub->getQuery()->getQuery() – Jordi Puigdellívol Aug 28 '15 at 14:23 ...
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What is the simplest SQL Query to find the second largest value?

... SELECT MAX( col ) FROM table WHERE col < ( SELECT MAX( col ) FROM table ) share | improve this answ...
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When to use Common Table Expression (CTE)

...ing well? Can someone give me a simple example of limitations with regular select, derived or temp table queries to make the case of CTE? Any simple examples would be highly appreciated. ...
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How do I use variables in Oracle SQL Developer?

... other stuff didn't work for me, but this did: define value1 = 'sysdate' SELECT &&value1 from dual; Also it's the slickest way presented here, yet. (If you omit the "define"-part you'll be prompted for that value) ...
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How do I use ROW_NUMBER()?

... For the first question, why not just use? SELECT COUNT(*) FROM myTable to get the count. And for the second question, the primary key of the row is what should be used to identify a particular row. Don't try and use the row number for that. If you returned Ro...