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How to count occurrences of a column value efficiently in SQL?
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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...
Count table rows
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SELECT COUNT(*) FROM fooTable;
will count the number of rows in the table.
See the reference manual.
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How to get multiple select box values using jQuery?
How to get multiple select box values using jQuery?
8 Answers
8
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SQL DROP TABLE foreign key constraint
...your table, you could use this SQL (if you're on SQL Server 2005 and up):
SELECT *
FROM sys.foreign_keys
WHERE referenced_object_id = object_id('Student')
and if there are any, with this statement here, you could create SQL statements to actually drop those FK relations:
SELECT
'ALTER TABL...
How to save MySQL query output to excel or .txt file? [duplicate]
...SV file:
MySQL provides an easy mechanism for writing the results of a select
statement into a text file on the server. Using extended options of
the INTO OUTFILE nomenclature, it is possible to create a comma
separated value (CSV) which can be imported into a spreadsheet
application suc...
How do I format date and time on ssrs report?
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Hope this helps:
SELECT convert(varchar, getdate(), 100) -- mon dd yyyy hh:mmAM
SELECT convert(varchar, getdate(), 101) -- mm/dd/yyyy – 10/02/2008
SELECT convert(varchar, getdate(), 102) -- yyyy.mm.dd – 2008.10.02 ...
How do you fix a bad merge, and replay your good commits onto a fixed merge?
...go, without me noticing it until now. I want to completely delete the file from the repository history.
12 Answers
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Android ImageView Zoom-in and Zoom-Out
... to the comment above. The same happens to me. Is there any way to stop it from zooming in on the first tap? The ImageView itself is set to centerFit.
– Baz
Feb 1 '13 at 13:57
30
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xcode-select active developer directory error
...red node-gyp ... but could be triggered by anything which requires xcode-select .
23 Answers
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How to set caret(cursor) position in contenteditable element (div)?
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In most browsers, you need the Range and Selection objects. You specify each of the selection boundaries as a node and an offset within that node. For example, to set the caret to the fifth character of the second line of text, you'd do the following:
function s...