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MySQL: @variable vs. variable. What's the difference?
...ialize this variable with a SET statement or inside a query:
SET @var = 1
SELECT @var2 := 2
When you develop a stored procedure in MySQL, you can pass the input parameters and declare the local variables:
DELIMITER //
CREATE PROCEDURE prc_test (var INT)
BEGIN
DECLARE var2 INT;
SET var2 =...
Archiving project in Xcode incorrectly creates multi-application bundle
...stall is set to No or which header files are causing the problem try this: Select the archive and click the Distribute button. Select the 'Save Built Products' option. Hit Next and Save. Browse the created directory in Finder. The 'libraries' subdirectory will identify the libraries that you need t...
How to get all columns' names for all the tables in MySQL?
...
select * from information_schema.columns
where table_schema = 'your_db'
order by table_name,ordinal_position
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How can I output a UTF-8 CSV in PHP that Excel will read properly?
...pen this file in TextEdit or TextMate or Dreamweaver and it displays UTF-8 characters properly, but if I open it in Excel it's doing this silly íÄ kind of thing instead. Here's what I've got at the head of my document:
...
How do I return to an older version of our code in Subversion?
...
If you are using TortoiseSVN, right-click the file select Merge, then Merge a Range of Revisions. In the log box type in 140-150 and click the Reverse Checkbox. After that, commit as usual. This will perform the same operation as Jon's example.
– DavGarc...
Count the occurrences of DISTINCT values
...
SELECT name,COUNT(*) as count
FROM tablename
GROUP BY name
ORDER BY count DESC;
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MYSQL OR vs IN performance
...for future Googlers. Total count of returned results is 7264 out of 10000
SELECT * FROM item WHERE id = 1 OR id = 2 ... id = 10000
This query took 0.1239 seconds
SELECT * FROM item WHERE id IN (1,2,3,...10000)
This query took 0.0433 seconds
IN is 3 times faster than OR
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Use email address as primary key?
... key. Email address may be a bit much, but a CASCADE UPDATE for a PK of 2-character country code isn't a big deal.
– Matthew Wood
Sep 27 '10 at 20:58
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html select only one checkbox in a group
So how can I only allow a user to select only one checkbox?
16 Answers
16
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SQL Server 2012 column identity increment jumping from 6 to 1000+ on 7th entry [duplicate]
...TrackerMessageId INT
DECLARE @intRowCount INT
SET @intRowCount = (SELECT COUNT(*) FROM INSERTED)
SET @intTrackerMessageId = (SELECT intIdentityLast FROM tblsysIdentities WHERE intTableId=1)
UPDATE tblsysIdentities SET intIdentityLast = @intTrackerMessageId + @intRowCount WHERE intT...