MySQL Tutorial/Math Numeric Functions/PI
PI() returns the value of |D (pi).
The default number of decimal places displayed is seven, but MySQL uses the full double-precision value internally.
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mysql> mysql> SELECT PI(); +----------+ | PI() | +----------+ | 3.141593 | +----------+ 1 row in set (0.00 sec) mysql> SELECT PI()+0.000000000000000000; +---------------------------+ | PI()+0.000000000000000000 | +---------------------------+ | 3.141592653589793100 | +---------------------------+ 1 row in set (0.00 sec) mysql></source>