DO
DO
DO - execute an anonymous code block
Synopsis
DO [ LANGUAGElang_name]code
Description
DO
executes an anonymous code block, or in other
words a transient anonymous function in a procedural language.
The code block is treated as though it were the body of a function
with no parameters, returning
void
. It is parsed and
executed a single time.
The optional
LANGUAGE
clause can be written either
before or after the code block.
Parameters
-
code -
The procedural language code to be executed. This must be specified as a string literal, just as in
CREATE FUNCTION. Use of a dollar-quoted literal is recommended. -
lang_name -
The name of the procedural language the code is written in. If omitted, the default is
plpgsql.
Notes
The procedural language to be used must already have been installed
into the current database by means of
CREATE EXTENSION
.
plpgsql
is installed by default, but other languages are not.
The user must have
USAGE
privilege for the procedural
language, or must be a superuser if the language is untrusted.
This is the same privilege requirement as for creating a function
in the language.
If
DO
is executed in a transaction block, then the
procedure code cannot execute transaction control statements. Transaction
control statements are only allowed if
DO
is executed in
its own transaction.
Examples
Grant all privileges on all views in schema
public
to
role
webuser
:
DO $$DECLARE r record;
BEGIN
FOR r IN SELECT table_schema, table_name FROM information_schema.tables
WHERE table_type = 'VIEW' AND table_schema = 'public'
LOOP
EXECUTE 'GRANT ALL ON ' || quote_ident(r.table_schema) || '.' || quote_ident(r.table_name) || ' TO webuser';
END LOOP;
END$$;
Compatibility
There is no
DO
statement in the SQL standard.