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1994.4.52
by Marisa Plumb
modifying folder structure |
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Aggregate Functions
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===================
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SQL group (aggregate) functions operate on sets of values. If you use an aggregate function in a statement containing no GROUP BY clause, it is equivalent to grouping on all rows. |
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General syntax for aggregate functions is: ::
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SELECT "function type" ("column_name")
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FROM "table_name";
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The following are examples of aggregate functions: |
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**AVG**: Return the average value of the argument. (Does not work with temporal values unless first converted to numeric values.)
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:doc:`count` |
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(DISTINCT): Return the count of a number of different values |
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:doc:`count`: Return a count of the number of rows returned |
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**GROUP_CONCAT**: Return a concatenated string
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**MAX**: Return the maximum value
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**MIN**: Return the minimum value
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**STD**: Return the population standard deviation
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**STDDEV_POP**: Return the population standard deviation
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**STDDEV_SAMP**: Return the sample standard deviation
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**STDDEV**: Return the population standard deviation
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**SUM**: Return the sum. (Does not work with temporal values unless first converted to numeric values.)
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**VAR_POP**: Return the population standard variance
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**VAR_SAMP**: Return the sample variance
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**VARIANCE**: Return the population standard variance
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.. toctree:: |
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:hidden:
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count |