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How can I select the first day of a month in SQL?
I just need to select the first day of the month of a given datetime variable.
30 Answers
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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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What is the equivalent of 'describe table' in SQL Server?
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use Select * From INFORMATION_SCHEMA.COLUMNS Where TABLE_NAME = 'TABLENAME' if you don't want to use a stored procedure
– Matias Elorriaga
Aug 4 '14 at 18:21
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must appear in the GROUP BY clause or be used in an aggregate function
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Yes, this is a common aggregation problem. Before SQL3 (1999), the selected fields must appear in the GROUP BY clause[*].
To workaround this issue, you must calculate the aggregate in a sub-query and then join it with itself to get the additional columns you'd need to show:
SELECT m.cname...
Find most frequent value in SQL column
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SELECT `column`,
COUNT(`column`) AS `value_occurrence`
FROM `my_table`
GROUP BY `column`
ORDER BY `value_occurrence` DESC
LIMIT 1;
Replace column and my_table. Increase 1 if you wa...
How to fetch the row count for all tables in a SQL SERVER database [duplicate]
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EXEC sp_MSForEachTable @command1='INSERT #counts (table_name, row_count) SELECT ''?'', COUNT(*) FROM ?'
SELECT table_name, row_count FROM #counts ORDER BY table_name, row_count DESC
DROP TABLE #counts
The output will be a list of tables and their row counts.
If you just want the total row count...
How to get number of rows using SqlDataReader in C#
...reading all rows (and then you might as well store them)
run a specialized SELECT COUNT(*) query beforehand.
Going twice through the DataReader loop is really expensive, you would have to re-execute the query.
And (thanks to Pete OHanlon) the second option is only concurrency-safe when you use a ...
Maximum number of characters using keystrokes A, Ctrl+A, Ctrl+C and Ctrl+V
...rate through for i up to n, doing two things: pressing A once and pressing select all + copy followed by paste j times (actually j-i-1 below; note the trick here: the contents are still in the clipboard, so we can paste it multiple times without copying each time). We only have to consider up to 4 c...
How do I convert an interval into a number of hours with postgres?
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Probably the easiest way is:
SELECT EXTRACT(epoch FROM my_interval)/3600
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Blank HTML SELECT without blank item in dropdown list
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Just use disabled and/or hidden attributes:
<option selected disabled hidden style='display: none' value=''></option>
selected makes this option the default one.
disabled makes this option unclickable.
style='display: none' makes this option not displayed in older ...