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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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How to check if a column exists in a SQL Server table?
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SQL Server 2005 onwards:
IF EXISTS(SELECT 1 FROM sys.columns
WHERE Name = N'columnName'
AND Object_ID = Object_ID(N'schemaName.tableName'))
BEGIN
-- Column Exists
END
Martin Smith's version is shorter:
IF COL_LENGTH('schemaName.tabl...
What is the difference between ExecuteScalar, ExecuteReader and ExecuteNonQuery?
... then the result is the first column of the first row. An example might be SELECT @@IDENTITY AS 'Identity'.
ExecuteReader is used for any result set with multiple rows/columns (e.g., SELECT col1, col2 from sometable).
ExecuteNonQuery is typically used for SQL statements without results (e.g., UPDATE...
How do I add an existing Solution to GitHub from Visual Studio 2013
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OK this worked for me.
Open the solution in Visual Studio 2013
Select File | Add to Source Control
Select the Microsoft Git Provider
That creates a local GIT repository
Surf to GitHub
Create a new repository DO NOT SELECT Initialize this repository with a README
That creates an em...
Replacement for “rename” in dplyr
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The next version of dplyr will support an improved version of select that also incorporates renaming:
> mtcars2 <- select( mtcars, disp2 = disp )
> head( mtcars2 )
disp2
Mazda RX4 160
Mazda RX4 Wag 160
Datsun 710 108
Hornet 4 Drive 258
H...
When restoring a backup, how do I disconnect all active connections?
... the steps (via: Tim Leung)
Right-click the server in Object Explorer and select 'Activity Monitor'.
When this opens, expand the Processes group.
Now use the drop-down to filter the results by database name.
Kill off the server connections by selecting the right-click 'Kill Process' option.
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How do I perform an insert and return inserted identity with Dapper?
...uerySingle<int>( @"
INSERT INTO [MyTable] ([Stuff]) VALUES (@Stuff);
SELECT CAST(SCOPE_IDENTITY() as int)", new { Stuff = mystuff});
Note that on more recent versions of SQL Server you can use the OUTPUT clause:
var id = connection.QuerySingle<int>( @"
INSERT INTO [MyTable] ([Stuff])
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SQLite select where empty?
In SQLite, how can I select records where some_column is empty?
Empty counts as both NULL and "".
4 Answers
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linq query to return distinct field values from a list of objects
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objList.Select(o=>o.typeId).Distinct()
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How to ignore SVN folders in WinMerge?
...ersion housekeeping directories
d: \\.svn$
d: \\._svn$
Save it, then when selecting items to merge, select the filter you defined from the Select Files or Folders dialog box. Bonus points: It will save this and use it as a default for future merges.
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