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When to use Common Table Expression (CTE)
...ing well? Can someone give me a simple example of limitations with regular select, derived or temp table queries to make the case of CTE? Any simple examples would be highly appreciated.
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How can I escape a double quote inside double quotes?
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Use a backslash:
echo "\"" # Prints one " character.
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How to drop all tables in a SQL Server database?
...VARCHAR(500) DECLARE @Cursor CURSOR
SET @Cursor = CURSOR FAST_FORWARD FOR
SELECT DISTINCT sql = 'ALTER TABLE [' + tc2.TABLE_SCHEMA + '].[' + tc2.TABLE_NAME + '] DROP [' + rc1.CONSTRAINT_NAME + '];'
FROM INFORMATION_SCHEMA.REFERENTIAL_CONSTRAINTS rc1
LEFT JOIN INFORMATION_SCHEMA.TABLE_CONSTRAINTS t...
Get selected option from select element
I am trying to get the selected option from a dropdown and populate another item with that text, as follows. IE is barking up a storm and it doesn't work in Firefox:
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Select row with most recent date per user
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Query:
SQLFIDDLEExample
SELECT t1.*
FROM lms_attendance t1
WHERE t1.time = (SELECT MAX(t2.time)
FROM lms_attendance t2
WHERE t2.user = t1.user)
Result:
| ID | USER | TIME | IO |
---------------------------...
Select2 doesn't work when embedded in a bootstrap modal
When I use a select2 (input) in bootstrap modal, I can't type anything into it. It's like disabled? Outside the modal select2 works fine.
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Removing rounded corners from a element in Chrome/Webkit
...sheet for Chrome gives a border-radius of 5px to all the corners of a <select> element. I've tried getting rid of this by applying a radius of 0px through my external stylesheet, as well inline on the element itself; I've tried both border-radius:0px and -webkit-border-radius:0px; and I...
How can I generate an MD5 hash?
... “LATIN1” != “ASCII” (or “US-ASCII”). ASCII is a 7-bit character set, Latin1 is an 8-bit character set. They are not the same.
– Bombe
Jan 7 '09 at 7:57
8
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Converting Select results into Insert script - SQL Server [closed]
...asier than installing plugins or external tools in some situations:
Do a select [whatever you need]INTO temp.table_namefrom [... etc ...].
Right-click on the database in the Object Explorer => Tasks => Generate Scripts
Select temp.table_name in the "Choose Objects" screen, click Next.
In the...
Simple way to calculate median with MySQL
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In MariaDB / MySQL:
SELECT AVG(dd.val) as median_val
FROM (
SELECT d.val, @rownum:=@rownum+1 as `row_number`, @total_rows:=@rownum
FROM data d, (SELECT @rownum:=0) r
WHERE d.val is NOT NULL
-- put some where clause here
ORDER BY d.val
) ...