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I have created the following tables.

First Table -

CREATE TABLE process

(

  process_name varchar(60) NOT NULL,

  fluid_id serial NOT NULL,

  fluid varchar(30) NOT NULL,

  ip_op_reactor varchar(3),

  source varchar(30),

  destination varchar(30),

  CONSTRAINT process_pk PRIMARY KEY (fluid_id)

);

---------

 Second Table -

CREATE TABLE specification

(

  fluid_id int4 NOT NULL,

  line_vessel_ident varchar(30),

  CONSTRAINT specification_pk PRIMARY KEY (fluid_id),

  CONSTRAINT specification_fluid_id_fk FOREIGN KEY (fluid_id) REFERENCES process (fluid_id)

);

On data entry I want the serial number generated in process.fluid_id to be transferred to column  specification.fluid_id.

A simple insert/select command will transfer the serial number but entering a second row then employing an insert/select command violates the p_k unique rule.

What do I need to do?

 Bob