Syntax:
DIV

Integer division. Similar to FLOOR(), but is safe with BIGINT values.

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: https://mariadb.com/kb/en/div/

