DISCARD

DISCARD
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DISCARD — discard session state

Synopsis

+DISCARD { ALL | PLANS | SEQUENCES | TEMPORARY | TEMP }
+

Description

+ DISCARD releases internal resources associated with a + database session. This command is useful for partially or fully + resetting the session's state. There are several subcommands to + release different types of resources; the DISCARD ALL + variant subsumes all the others, and also resets additional state. +

Parameters

PLANS

+ Releases all cached query plans, forcing re-planning to occur + the next time the associated prepared statement is used. +

SEQUENCES

+ Discards all cached sequence-related state, + including currval()/lastval() + information and any preallocated sequence values that have not + yet been returned by nextval(). + (See CREATE SEQUENCE for a description of + preallocated sequence values.) +

TEMPORARY or TEMP

+ Drops all temporary tables created in the current session. +

ALL

+ Releases all temporary resources associated with the current + session and resets the session to its initial state. + Currently, this has the same effect as executing the following sequence + of statements: +

+CLOSE ALL;
+SET SESSION AUTHORIZATION DEFAULT;
+RESET ALL;
+DEALLOCATE ALL;
+UNLISTEN *;
+SELECT pg_advisory_unlock_all();
+DISCARD PLANS;
+DISCARD TEMP;
+DISCARD SEQUENCES;
+

Notes

+ DISCARD ALL cannot be executed inside a transaction block. +

Compatibility

+ DISCARD is a PostgreSQL extension. +