deferred capability for the primary key

Fellow postgresers:

According to the web site the following syntax is permitted:

PRIMARY KEY clause

SQL92 specifies some additional capabilities for PRIMARY KEY:

Table Constraint definition:

[ CONSTRAINT name ] PRIMARY KEY ( column [, ...] )
[ {INITIALLY DEFERRED | INITIALLY IMMEDIATE} ]
[ [ NOT ] DEFERRABLE ]

My snytax is:

constraint base_pos_pkey primary key (base, pos)
initially deferred

Postgres complained about the "initially"

Are deferrable primary keys not supported by Postgres?

Thanks!

Merrill

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