What Are Group Functions

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What Are Group Functions? - Oracle DBA FAQ - Understanding SQL SELECT Query Statements

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Group functions are functions applied to a group of rows. Examples of group functions are:

COUNT(*) - Returns the number of rows in the group.
MIN(exp) - Returns the minimum value of the expression evaluated on each row of the group.
MAX(exp) - Returns the maximum value of the expression evaluated on each row of the group.
AVG(exp) - Returns the average value of the expression evaluated on each row of the group.

2007-04-20, 4842👍, 0💬

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Can Group Functions Be Mixed with Non-group Selection Fields
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How To Use Group Functions in the SELECT Clause
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