Divides one number by another and sets a value to the result of the operation. For example, if a variable @x equals 34, then @x /= 2 takes the original value of @x, divides by 2 and sets @x to that new value (17).
Transact-SQL Syntax Conventions

Syntax

Arguments
-
expression
-
Is any valid expression of any one of the data types in the numeric category except the bit data type.

Remarks

Result Types

See Also