大约有 46,000 项符合查询结果(耗时:0.0243秒) [XML]

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Insert Data Into Temp Table with Query

... SELECT * INTO #Temp FROM (SELECT Received, Total, Answer, (CASE WHEN application LIKE '%STUFF%' THEN 'MORESTUFF' END) AS application FROM FirstTable WHERE Recieved = 1 AND applicati...
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Unioning two tables with different number of columns

... Add extra columns as null for the table having less columns like Select Col1, Col2, Col3, Col4, Col5 from Table1 Union Select Col1, Col2, Col3, Null as Col4, Null as Col5 from Table2 share | ...
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Multiple select statements in Single query

... SELECT ( SELECT COUNT(*) FROM user_table ) AS tot_user, ( SELECT COUNT(*) FROM cat_table ) AS tot_cat, ( SELECT COUNT(*) FROM course_table ) AS tot_course ...
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How to select rows with no matching entry in another table?

... Here's a simple query: SELECT t1.ID FROM Table1 t1 LEFT JOIN Table2 t2 ON t1.ID = t2.ID WHERE t2.ID IS NULL The key points are: LEFT JOIN is used; this will return ALL rows from Table1, regardless of whether or not there is a matching row i...
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DISTINCT for only one column

... If you are using SQL Server 2005 or above use this: SELECT * FROM ( SELECT ID, Email, ProductName, ProductModel, ROW_NUMBER() OVER(PARTITION BY Email ORDER BY ...
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How to set variable from a SQL query?

... Using SELECT: SELECT @ModelID = m.modelid FROM MODELS m WHERE m.areaid = 'South Coast' Using SET: SET @ModelID = (SELECT m.modelid FROM MODELS m WHERE m.areaid = 'South Coast') See this...
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Include headers when using SELECT INTO OUTFILE?

... You'd have to hard code those headers yourself. Something like: SELECT 'ColName1', 'ColName2', 'ColName3' UNION ALL SELECT ColName1, ColName2, ColName3 FROM YourTable INTO OUTFILE '/path/outfile' share ...
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Rails select helper - Default selected value, how?

... This should do it: <%= f.select :project_id, @project_select, :selected => params[:pid] %> share | improve this answer | ...
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How to select a single field for all documents in a MongoDB collection?

...nt such as: db.student.find({}, {roll:1, _id:0}) The above statement will select all documents in the students collection, and the returned document will return only the roll field (and exclude the _id). If we don't mention _id:0 the fields returned will be roll and _id. The '_id' field is always d...
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PostgreSQL return result set as JSON array?

... TL;DR SELECT json_agg(t) FROM t for a JSON array of objects, and SELECT json_build_object( 'a', json_agg(t.a), 'b', json_agg(t.b) ) FROM t for a JSON object of arrays. List of objects This section de...