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How do I declare and assign a variable on a single line in SQL
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You can also initialize from a select statement, eg: declare @eid uniqueidentifier = (select top 1 id from t_Event)
– Damien Sawyer
Sep 8 '16 at 20:32
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CSS “and” and “or”
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&& works by stringing-together multiple selectors like-so:
<div class="class1 class2"></div>
div.class1.class2
{
/* foo */
}
Another example:
<input type="radio" class="class1" />
input[type="radio"].class1
{
/* foo */
}
|| works by se...
Logcat not displaying my log calls
...DDMS perspective, make sure the correct device (propably emulator-xxxx) is selected and highlighted. Only then will you get the logcat output in the logcat view.
Also, the Android plugin is a bit quircky, and sometimes only shows the last line in the logcat view. If this happens, try to clear the l...
DropDownList's SelectedIndexChanged event not firing
I have a DropDownList object in my web page. When I click on it and select a different value, nothing happens, even though I have a function wired up to the SelectedIndexChanged event.
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Is having an 'OR' in an INNER JOIN condition a bad idea?
... a MERGE JOIN.
It can be expressed as a concatenation of two resultsets:
SELECT *
FROM maintable m
JOIN othertable o
ON o.parentId = m.id
UNION
SELECT *
FROM maintable m
JOIN othertable o
ON o.id = m.parentId
, each of them being an equijoin, however, SQL Server's optimiz...
How do I drop a function if it already exists?
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IF EXISTS (
SELECT * FROM sysobjects WHERE id = object_id(N'function_name')
AND xtype IN (N'FN', N'IF', N'TF')
)
DROP FUNCTION function_name
GO
If you want to avoid the sys* tables, you could instead do (from here in example A...
What is the difference between Views and Materialized Views in Oracle?
... you. The downside of a view is that its performance depends on how good a select statement the view is based on. If the select statement used by the view joins many tables, or uses joins based on non-indexed columns, the view could perform poorly.
Materialized views
They are similar to regular vi...
How to automatically indent source code?
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Ctrl+E, D - Format whole doc
Ctrl+K, Ctrl+F - Format selection
Also available in the menu via Edit|Advanced.
Thomas
Edit-
Ctrl+K, Ctrl+D - Format whole doc in VS 2010
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Two single-column indexes vs one two-column index in MySQL?
... the statement I provided.
Additionally, MySQL can only use one index per SELECT so a covering index would be the best means of optimizing your queries.
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How do I grant myself admin access to a local SQL Server instance?
...he "SQL Server Configuration Manager", right click the server instance and select properties, go to the tab "Startup Parameters" and add -m.
– maets
May 5 '15 at 13:32
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