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How to drop a table if it exists?
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Is it correct to do the following?
IF EXISTS(SELECT *
FROM dbo.Scores)
DROP TABLE dbo.Scores
No. That will drop the table only if it contains any rows (and will raise an error if the table does not exist).
Instead, for a permanent table you can use
I...
How to select .NET 4.5.2 as a target framework in Visual Studio
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onDemand: true,
discardSelector: ".discard-answer"
,immediatelyShowMarkdownHelp:true,enableSnippets:true
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How do I create a category in Xcode 6 or higher?
...ey just moved it without telling anyone.
Click File -> New -> File
Select Objective-C file under Sources in iOS or Mac OS respectively and Click Next
Now under File Type: choose either Category, Protocol, or Extension
PS. Under File Name: whatever you type here will be either the Category,...
Best way to organize jQuery/JavaScript code (2013) [closed]
... var parent = "";
if(selected_folder != "" ){
parent = selected_folder+" .content";
}
$R.find(".layer").clone()
.addClass(name).html(...
Compare dates in MySQL
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You can try below query,
select * from players
where
us_reg_date between '2000-07-05'
and
DATE_ADD('2011-11-10',INTERVAL 1 DAY)
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im...
Get full path of the files in PowerShell
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Add | select FullName to the end of your line above. If you need to actually do something with that afterwards, you might have to pipe it into a foreach loop, like so:
get-childitem "C:\windows\System32" -recurse | where {$_.exte...
iOS 5 Best Practice (Release/retain?)
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@Dan: You're not joking it can be selectively turned off? Please give a link, that is important to me! :D
– sudo rm -rf
Jun 10 '11 at 15:43
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SQL standard to escape column names?
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For MySQL, use back ticks `.
For instance:
SELECT `column`, `column2` FROM `table`
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How to identify all stored procedures referring a particular table
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SELECT Name
FROM sys.procedures
WHERE OBJECT_DEFINITION(OBJECT_ID) LIKE '%TableNameOrWhatever%'
BTW -- here is a handy resource for this type of question: Querying the SQL Server System Catalog FAQ
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postgresql COUNT(DISTINCT …) very slow
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You can use this:
SELECT COUNT(*) FROM (SELECT DISTINCT column_name FROM table_name) AS temp;
This is much faster than:
COUNT(DISTINCT column_name)
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