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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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Using Chrome, how to find to which events are bound to an element
...e Event you need
From the handler property, right click over function and select 'Show function definition'
You will now see the Event binding code
Click on the 'Pretty print' button for a more readable view of the code
sh...
What is a stored procedure?
...
CREATE PROCEDURE Users_GetUserInfo
@login nvarchar(30)=null
AS
SELECT * from [Users]
WHERE ISNULL(@login,login)=login
A benefit of stored procedures is that you can centralize data access logic into a single place that is then easy for DBA's to optimize. Stored procedures also have...
Want to find records with no associated records in Rails
... get everyone with no friends in the first case:
Person.where('id NOT IN (SELECT DISTINCT(person_id) FROM friends)')
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Block commenting in Ruby
...
In TextMate, you can alt-drag vertically to select a column of text. This will duplicate the insertion point across all the lines you select, so you can insert or delete multiple #s at once.
UPDATE: Also in TextMate, assuming you have the right language selected, Cmd ...
Reading CSV file and storing values into an array
...
LINQ way:
var lines = File.ReadAllLines("test.txt").Select(a => a.Split(';'));
var csv = from line in lines
select (from piece in line
select piece);
^^Wrong - Edit by Nick
It appears the original answerer was attempting to populate csv with a...
Run PostgreSQL queries from the command line
...
psql -U username -d mydatabase -c 'SELECT * FROM mytable'
If you're new to postgresql and unfamiliar with using the command line tool psql then there is some confusing behaviour you should be aware of when you've entered an interactive session.
For example, ...
How to make ng-repeat filter out duplicate results
... unique filter) and use it directly in the ng-options (or ng-repeat).
<select ng-model="orderProp" ng-options="place.category for place in places | unique:'category'">
<option value="0">Default</option>
// unique options from the categories
</select>
...
Insert multiple rows WITHOUT repeating the “INSERT INTO …” part of the statement?
...
INSERT INTO dbo.MyTable (ID, Name)
SELECT 123, 'Timmy'
UNION ALL
SELECT 124, 'Jonny'
UNION ALL
SELECT 125, 'Sally'
For SQL Server 2008, can do it in one VALUES clause exactly as per the statement in your question (you just need to add a comma to separate eac...
“405 method not allowed” in IIS7.5 for “PUT” method
...ick on "WebDAV".
5.Click on "Request Restrictions".
6.In the tab "Verbs" select "All verbs" .
7.Press OK.
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