大约有 40,000 项符合查询结果(耗时:0.0247秒) [XML]

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How to get the caret column (not pixels) position in a textarea, in characters, from the start?

...refox, Safari (and other Gecko based browsers) you can easily use textarea.selectionStart, but for IE that doesn't work, so you will have to do something like this: function getCaret(node) { if (node.selectionStart) { return node.selectionStart; } else if (!document.selection) { return ...
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How to set selected value on select using selectpicker plugin from bootstrap

I'm using the Bootstrap-Select plugin like this: 18 Answers 18 ...
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Rails: select unique values from a column

... Model.select(:rating) Result of this is a collection of Model objects. Not plain ratings. And from uniq's point of view, they are completely different. You can use this: Model.select(:rating).map(&:rating).uniq or this (mo...
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typecast string to integer - Postgres

...ur value is an empty string, you can use NULLIF to replace it for a NULL: SELECT NULLIF(your_value, '')::int share | improve this answer | follow | ...
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how to exclude null values in array_agg like in string_agg using postgres?

... SQL Fiddle select id, (select array_agg(a) from unnest(canonical_users) a where a is not null) canonical_users, (select array_agg(a) from unnest(non_canonical_users) a where a is not null) non_canonical_users from ( SELE...
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How to count occurrences of a column value efficiently in SQL?

... This should work: SELECT age, count(age) FROM Students GROUP by age If you need the id as well you could include the above as a sub query like so: SELECT S.id, S.age, C.cnt FROM Students S INNER JOIN (SELECT age, count(age) a...
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In SQL, how can you “group by” in ranges?

...version. Here are the correct versions of both of them on SQL Server 2000. select t.range as [score range], count(*) as [number of occurences] from ( select case when score between 0 and 9 then ' 0- 9' when score between 10 and 19 then '10-19' else '20-99' end as range from scores)...
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Selecting a row in DataGridView programmatically

How can I select a particular range of rows in a DataGridView programmatically at runtime? 8 Answers ...
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How to calculate age (in years) based on Date of Birth and getDate()

...low: try this: DECLARE @dob datetime SET @dob='1992-01-09 00:00:00' SELECT DATEDIFF(hour,@dob,GETDATE())/8766.0 AS AgeYearsDecimal ,CONVERT(int,ROUND(DATEDIFF(hour,@dob,GETDATE())/8766.0,0)) AS AgeYearsIntRound ,DATEDIFF(hour,@dob,GETDATE())/8766 AS AgeYearsIntTrunc OUTPUT: Age...
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What is the difference between “INNER JOIN” and “OUTER JOIN”?

...he intersection of the two tables, i.e. the two rows they have in common. select * from a INNER JOIN b on a.a = b.b; select a.*, b.* from a,b where a.a = b.b; a | b --+-- 3 | 3 4 | 4 Left outer join A left outer join will give all rows in A, plus any common rows in B. select * from a LEFT OUT...