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How to convert timestamp to datetime in MySQL?
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SELECT from_unixtime( TIMESTAMP( "2011-12-01", "22:01:23.048" ) ) doesn't work. why? using v5.6
– Janus Troelsen
Feb 4 '14 at 18:44
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How do I use Linq to obtain a unique list of properties from a list of objects?
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IEnumerable<int> ids = list.Select(x=>x.ID).Distinct();
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Get all column names of a DataTable into string array using (LINQ/Predicate)
...es = dt.Columns.Cast<DataColumn>()
.Select(x => x.ColumnName)
.ToArray();
or in LINQ Query syntax:
string[] columnNames = (from dc in dt.Columns.Cast<DataColumn>()
select dc.ColumnName).To...
Add support library to Android Studio project
...oject Structure (Press F4 on PC and Command+; on MAC) on your project).
2.Select Modules on the left pane.
3.Choose your project and you will see Dependencies TAB above the third Column.
4.Click on the plus sign in the bottom. Then a tree-based directory chooser dialog will pop up, navigate to yo...
Javascript trick for 'paste as plain text` in execCommand
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content = window.clipboardData.getData('Text');
document.selection.createRange().pasteHTML(content);
}
});
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MySQL CONCAT returns NULL if any field contain NULL
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convert the NULL values with empty string by wrapping it in COALESCE
SELECT CONCAT(COALESCE(`affiliate_name`,''),'-',COALESCE(`model`,''),'-',COALESCE(`ip`,''),'-',COALESCE(`os_type`,''),'-',COALESCE(`os_version`,'')) AS device_name
FROM devices
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JavaScript: how to change form action attribute value based on selection?
I'm trying to change the form action based on the selected value from a dropdown menu.
5 Answers
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What are the use cases for selecting CHAR over VARCHAR in SQL?
...'123 Main St Washington, MD 12345', 123.45)
create view vwStagingTable AS
SELECT CustomerFirstName = CAST(CustomerFirstName as CHAR(30)),
CustomerLastName = CAST(CustomerLastName as CHAR(30)),
CustomerCityStateZip = CAST(CustomerCityStateZip as CHAR(100)),
CustomerCurrentBalance = CAST(CAST(Custome...
configure: error: C compiler cannot create executables
...'ve installed Xcode 4.3.x, you need to launch it, go into its preferences, select the Downloads tab, and click "Install" next to the Command Line Tools package.
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How to avoid mysql 'Deadlock found when trying to get lock; try restarting transaction'
...now() - INTERVAL 900 SECOND
To
DELETE FROM onlineusers
WHERE id IN (
SELECT id FROM onlineusers
WHERE datetime <= now() - INTERVAL 900 SECOND
ORDER BY id
) u;
Another thing to keep in mind is that mysql documentation suggest that in case of a deadlock the client should retry autom...