This topic describes the aggregate functions. Some functions are not supported by DRDS.

Supported functions

The following table describes the aggregate functions that are supported by DRDS.

Function Description
AVG() Return the average value of the argument
COUNT() Return a count of the number of rows returned
COUNT(DISTINCT) Return the count of a number of different values
MAX() Return the maximum value
MIN() Return the minimum value
SUM() Return the sum

Unsupported functions

The following table describes the aggregate functions that are not supported by DRDS. These functions are supported by databases that run on the MySQL 5.7 engine.

Function Description
BIT_AND() Return bitwise AND
BIT_OR() Return bitwise OR
BIT_XOR() Return bitwise XOR
GROUP_CONCAT() Return a concatenated string
STD() Return the population standard deviation
STDDEV() Return the population standard deviation
STDDEV_POP() Return the population standard deviation
STDDEV_SAMP() Return the sample standard deviation
VAR_POP() Return the population standard variance
VAR_SAMP() Return the sample variance
VARIANCE() Return the population standard variance