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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, ...
What does “The APR based Apache Tomcat Native library was not found” mean?
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Rename Pandas DataFrame Index
...ut with df.rename() only the column name is renamed. Bug? I'm on version 0.12.0
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MySQL: What's the difference between float and double?
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They both represent floating point numbers. A FLOAT is for single-precision, while a DOUBLE is...
What is /dev/null 2>&1?
... the same net effect. I usually just use > for that reason.)
2>&1 redirects standard error (2) to standard output (1), which then discards it as well since standard output has already been redirected.
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Find which version of package is installed with pip
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Is there a difference between x++ and ++x in java?
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How to form tuple column from two columns in Pandas
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edited Nov 7 '16 at 16:58
answered Apr 17 '13 at 19:24
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