User-defined SQL functions

User-defined SQL functions let you define and store commonly-used SQL expressions as a function. User-defined SQL functions are useful for executing complex queries and combining Vertica built-in functions. You simply call the function name you assigned in your query.

A user-defined SQL function can be used anywhere in a query where an ordinary SQL expression can be used, except in a table partition clause or the projection segmentation clause.

For syntax and parameters for the commands and system table discussed in this section, see the following topics:

• CREATE FUNCTION

• ALTER FUNCTION (scalar)
• DROP FUNCTION
• GRANT (user defined extension)
• REVOKE (user defined extension)

• V_CATALOG.USER_FUNCTIONS