var_samp,variance_samp

Description

Returns the sample variance of an expression. Since v2.5.10, this function can also be used as a window function.

Syntax

VAR_SAMP(expr)

Parameters

expr: the expression. If it is a table column, it must evaluate to TINYINT, SMALLINT, INT, BIGINT, LARGEINT, FLOAT, DOUBLE, or DECIMAL.

Return value

Returns a DOUBLE value.

Examples

MySQL > select var_samp(scan_rows)
from log_statis
group by datetime;
+-----------------------+
| var_samp(`scan_rows`) |
+-----------------------+
|    5.6227132145741789 |
+-----------------------+

keyword

VAR_SAMP,VARIANCE_SAMP,VAR,SAMP,VARIANCE