大约有 47,000 项符合查询结果(耗时:0.0400秒) [XML]

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Pad a string with leading zeros so it's 3 characters long in SQL Server 2008

... If the field is already a string, this will work SELECT RIGHT('000'+ISNULL(field,''),3) If you want nulls to show as '000' It might be an integer -- then you would want SELECT RIGHT('000'+CAST(field AS VARCHAR(3)),3) As required by the question this answer only w...
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How to delete duplicate rows in SQL Server?

... are deleted (or updated), therefore just change the DELETE FROM CTE... to SELECT * FROM CTE: WITH CTE AS( SELECT [col1], [col2], [col3], [col4], [col5], [col6], [col7], RN = ROW_NUMBER()OVER(PARTITION BY col1 ORDER BY col1) FROM dbo.Table1 ) DELETE FROM CTE WHERE RN > 1 DEMO (re...
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How to find all duplicate from a List? [duplicate]

...d then filter out any of the enumerables that have a Count of <=1, then select their keys to get back down to a single enumerable: var duplicateKeys = list.GroupBy(x => x) .Where(group => group.Count() > 1) .Select(group => group.Key); ...
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The multi-part identifier could not be bound

...tion is specified in the WHERE clause). Here's an outline of your query: SELECT … FROM a, b LEFT JOIN dkcd ON … WHERE … You are probably expecting it to behave like this: SELECT … FROM (a, b) LEFT JOIN dkcd ON … WHERE … that is, the combination of tables a and b is joined with...
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How to check if field is null or empty in MySQL?

... Either use SELECT IF(field1 IS NULL or field1 = '', 'empty', field1) as field1 from tablename or SELECT case when field1 IS NULL or field1 = '' then 'empty' else field1 end as field1 from tablename ...
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What are the most common SQL anti-patterns? [closed]

...ost programmers' tendency to mix their UI-logic in the data access layer: SELECT FirstName + ' ' + LastName as "Full Name", case UserRole when 2 then "Admin" when 1 then "Moderator" else "User" end as "User's Role", case SignedIn when 0 then "Logged i...
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Postgresql aggregate array

... Use array_agg: http://www.sqlfiddle.com/#!1/5099e/1 SELECT s.name, array_agg(g.Mark) as marks FROM student s LEFT JOIN Grade g ON g.Student_id = s.Id GROUP BY s.Id By the way, if you are using Postgres 9.1, you don't need to repeat the columns on SELECT to GROUP BY,...
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How to create json by JavaScript for loop?

I have array of select tag. 5 Answers 5 ...
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MySQL case insensitive select

Can anyone tell me if a MySQL SELECT query is case sensitive or case insensitive by default? And if not, what query would I have to send so that I can do something like: ...
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How to sleep for five seconds in a batch file/cmd [duplicate]

...specify the timeout in seconds and the /D parameter to specify the default selection and ignore then selected choice. The one thing that might be an issue is if the user types one of the choice characters before the timeout period elapses. A partial work-around is to obfuscate the situation -- use ...