Syntax:
DIV

Integer division. Discards from the division result any fractional part
to the right of the decimal point.

As of MySQL 5.5.3, if either operand has a noninteger type, the
operands are converted to DECIMAL and divided using DECIMAL arithmetic
before converting the result to BIGINT. If the result exceeds BIGINT
range, an error occurs. Before MySQL 5.5.3, incorrect results may occur
for noninteger operands that exceed BIGINT range.

URL: http://dev.mysql.com/doc/refman/5.5/en/arithmetic-functions.html

