Provided by: postgresql-client-8.0_8.0.7-2build1_i386 bug

NAME

       ALTER DOMAIN - change the definition of a domain

SYNOPSIS

       ALTER DOMAIN name
           { SET DEFAULT expression | DROP DEFAULT }
       ALTER DOMAIN name
           { SET | DROP } NOT NULL
       ALTER DOMAIN name
           ADD domain_constraint
       ALTER DOMAIN name
           DROP CONSTRAINT constraint_name [ RESTRICT | CASCADE ]
       ALTER DOMAIN name
           OWNER TO new_owner

DESCRIPTION

       ALTER  DOMAIN  changes the definition of an existing domain.  There are
       several sub-forms:

       SET/DROP DEFAULT
              These forms set or remove the default value for a  domain.  Note
              that  defaults only apply to subsequent INSERT commands; they do
              not affect rows already in a table using the domain.

       SET/DROP NOT NULL
              These forms change whether a domain  is  marked  to  allow  NULL
              values  or to reject NULL values. You may only SET NOT NULL when
              the columns using the domain contain no null values.

       ADD domain_constraint
              This form adds a new constraint  to  a  domain  using  the  same
              syntax  as  CREATE  DOMAIN  [create_domain(7)].   This will only
              succeed  if  all  columns  using  the  domain  satisfy  the  new
              constraint.

       DROP CONSTRAINT
              This form drops constraints on a domain.

       OWNER  This form changes the owner of the domain to the specified user.

       You must own the domain to use ALTER DOMAIN; except  for  ALTER  DOMAIN
       OWNER, which may only be executed by a superuser.

PARAMETERS

       name   The  name  (possibly  schema-qualified) of an existing domain to
              alter.

       domain_constraint
              New domain constraint for the domain.

       constraint_name
              Name of an existing constraint to drop.

       CASCADE
              Automatically drop objects that depend on the constraint.

       RESTRICT
              Refuse to  drop  the  constraint  if  there  are  any  dependent
              objects. This is the default behavior.

       new_owner
              The user name of the new owner of the domain.

EXAMPLES

       To add a NOT NULL constraint to a domain:

       ALTER DOMAIN zipcode SET NOT NULL;

       To remove a NOT NULL constraint from a domain:

       ALTER DOMAIN zipcode DROP NOT NULL;

       To add a check constraint to a domain:

       ALTER DOMAIN zipcode ADD CONSTRAINT zipchk CHECK (char_length(VALUE) = 5);

       To remove a check constraint from a domain:

       ALTER DOMAIN zipcode DROP CONSTRAINT zipchk;

COMPATIBILITY

       The  ALTER DOMAIN statement is compatible with SQL:1999, except for the
       OWNER variant, which is a PostgreSQL extension.