Postgres-XC 1.1 Documentation
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# DO

## Name

DO -- execute an anonymous code block

## Synopsis

    DO [ LANGUAGE lang_name ] code

## Description

> Note: At present, this section is just taken from PostgreSQL documentation and is subject to revision for Postgres-XC.

`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 LANGUAGE`. `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.

## 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.

## See Also

CREATE LANGUAGE

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