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COUNT(*) vs. COUNT(1) vs. COUNT(pk): which is better? [duplicate]
...T(tableHere) or COUNT(tableHere.*), use that.
In short, don't use COUNT(1) for anything. It's a one-trick pony, which rarely does what you want, and in those rare cases is equivalent to count(*)
Use count(*) for counting
Use * for all your queries that need to count everything, even for joins, ...
How to explain callbacks in plain english? How are they different from calling one function from ano
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Cryptic “Script Error.” reported in Javascript in Chrome and Firefox
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How to access outer class from an inner class?
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Run certain code every n seconds [duplicate]
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edited May 12 '19 at 9:55
albert
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How to run a shell script on a Unix console or Mac terminal?
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edited Feb 4 '14 at 16:04
answered Apr 9 '09 at 11:58
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What are the best practices for structuring a large Meteor app with many HTML template files? [close
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How to maintain a Unique List in Java?
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You can use a Set implementation:
Some info from the JAVADoc:
A collection that contains ...
How to efficiently count the number of keys/properties of an object in JavaScript?
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edited May 6 '19 at 19:36
Community♦
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answered Feb 3 '11 at 17:47
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