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MySQL how to join tables on two fields
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SELECT *
FROM t1
JOIN t2 USING (id, date)
perhaps you'll need to use INNEER JOIN or
where t2.id is not null
if you want results only matching both conditions
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jQuery hasAttr checking to see if there is an attribute on an element [duplicate]
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What about api.jquery.com/has-attribute-selector
– Aamir Afridi
Jan 30 '13 at 14:19
3
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How to check if a value exists in an array in Ruby
... match.
Don't use these:
# bad examples
array.grep(element).any?
array.select { |each| each == element }.size > 0
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Using only CSS, show div on hover over
...>Stuff shown on hover</div>
This uses the adjacent sibling selector, and is the basis of the suckerfish dropdown menu.
HTML5 allows anchor elements to wrap almost anything, so in that case the div element can be made a child of the anchor. Otherwise the principle is the same - use ...
What is the difference between mutex and critical section?
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The 'fast' Windows equal of critical selection in Linux would be a futex, which stands for fast user space mutex. The difference between a futex and a mutex is that with a futex, the kernel only becomes involved when arbitration is required, so you save the over...
JSLint: was used before it was defined
...tive respects function scope.
Some globals can be predefined for you. Select the Assume a browser (browser) option to predefine the standard global properties that are supplied by web browsers, such as document and addEventListener.
Example:
/*jslint browser: true*/
/*global $, jQuery*/
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How to fix the Hibernate “object references an unsaved transient instance - save the transient insta
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For merge, it runs a SELECT query. Otherwise, it checks the id and the version.
– Vlad Mihalcea
Sep 4 at 3:46
add a comme...
What database does Google use?
... with different time stamps. The time stamp allows for operations such as "select 'n' versions of this Web page" or "delete cells that are older than a specific date/time."
In order to manage the huge tables, Bigtable splits tables at row boundaries and saves them as tablets. A tablet is around 20...
How to debug PDO database queries?
...gt;setAttribute( PDO::ATTR_ERRMODE, PDO::ERRMODE_WARNING );
$db->query('SELECT *******');
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What should every programmer know about security? [closed]
...opinion. You can essentially be targeted just because of the platform you select, rather than any real interest in your assets. Think about all of the security holes that are found in 3rd party platforms, and all of the products that are instantly vulnerable just because they use it. I wouldn't b...