postgresql truncate code example
Example 1: restart identity cascade
TRUNCATE <table_name> RESTART IDENTITY CASCADE;
--RESTART will reset the identity sequence
--CASCADE all tables that have a foreign key reference to
--table_name will be truncated as well
Example 2: postgres clear table
TRUNCATE [ TABLE ] [ ONLY ] name [ * ] [, ... ]
[ RESTART IDENTITY | CONTINUE IDENTITY ] [ CASCADE | RESTRICT ]