SHOW FUNCTIONS
Shows the list of supported functions currently, including builtin scalar/aggregate functions and user-defined functions.
Syntax
SHOW FUNCTIONS  [LIKE 'pattern' | WHERE expr]
Example
SHOW FUNCTIONS;
+-------------------------+------------+--------------+-------------------+---------------------------+
| name                    | is_builtin | is_aggregate | definition        | description               |
+-------------------------+------------+--------------+-------------------+---------------------------+
| !=                      |          1 |            0 |                   |                           |
| %                       |          1 |            0 |                   |                           |
| *                       |          1 |            0 |                   |                           |
| +                       |          1 |            0 |                   |                           |
| -                       |          1 |            0 |                   |                           |
| /                       |          1 |            0 |                   |                           |
| <                       |          1 |            0 |                   |                           |
| <=                      |          1 |            0 |                   |                           |
| <>                      |          1 |            0 |                   |                           |
| =                       |          1 |            0 |                   |                           |
+-------------------------+------------+--------------+-------------------+---------------------------+
Showing the functions begin with "today":
SHOW FUNCTIONS LIKE 'today%';
+--------------+------------+--------------+------------+-------------+
| name         | is_builtin | is_aggregate | definition | description |
+--------------+------------+--------------+------------+-------------+
| today        |          1 |            0 |            |             |
| todayofmonth |          1 |            0 |            |             |
| todayofweek  |          1 |            0 |            |             |
| todayofyear  |          1 |            0 |            |             |
+--------------+------------+--------------+------------+-------------+
Showing the functions begin with "today" with WHERE:
SHOW FUNCTIONS WHERE name LIKE 'today%';
+--------------+------------+--------------+------------+-------------+
| name         | is_builtin | is_aggregate | definition | description |
+--------------+------------+--------------+------------+-------------+
| today        |          1 |            0 |            |             |
| todayofmonth |          1 |            0 |            |             |
| todayofweek  |          1 |            0 |            |             |
| todayofyear  |          1 |            0 |            |             |
+--------------+------------+--------------+------------+-------------+