MySQL has a full set of arithmetic, comparison, and logical operators. You need to be careful when using operators with NULL because this does not always produce the expected results.
MySQL provides a set of functions that can be used to perform string, numeric, date, casting, and miscellaneous functions.
The grouping functions are performed over a set of column values. These sets are groups if a GROUP BY clause is specified, or they provide the complete set of returned values in a column if no GROUP BY clause is specified.
