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postgresql: using NEW.* in dynamic command for EXECUTE

i try to create a plpgsql trigger for postgresql 8.3 which automatically partitions a table on before insert by the id column

if the destination table doesnt exist it will be created, and the insert goes there

so i created the insert statement with the new table name like this

exec_insert := 'INSERT INTO '||TG_TABLE_SCHEMA||'.'||TG_RELNAME||'_'||destinationid||' VALUES('||NEW.*||')';
EXECUTE exec_insert;

resulting in the error:

ERROR:  NEW used in query that is not in a rule

i have 2 questions:

  1. is it even possible to use NEW in EXECUTE or is t开发者_运维问答here some mistake in the statement?
  2. if its just not possible, anyone knows how to get the values out of NEW so i can use them in the statement? the only thing which comes to my mind is using information_schema to retrieve column names for the main table and then try to access NEW's values dynamically - which i also dont know how :(

thx


You could use

...
_sql varchar(100)= 'insert into some_table values ($1.*)';
...
execute _sql using new;
...

I found this hidden in some remote areas :D . I am using 9.1


This setup works fine over here (version 8.4 and 9.0):

CREATE TABLE customer
(
  id bigserial NOT NULL,
  name text,
  datecreated timestamp with time zone DEFAULT now(),
  CONSTRAINT customer_pkey PRIMARY KEY (id) USING INDEX TABLESPACE pg_default
);

CREATE OR REPLACE FUNCTION test_trigger()
  RETURNS trigger AS
$BODY$
declare
    query   text;
begin
    query := 'INSERT INTO customer_' || substring(NEW.name,1,1) || ' VALUES(' || NEW.id || ','''|| NEW.name||''')';
    EXECUTE query;

    RETURN NULL;

    EXCEPTION
        WHEN undefined_table THEN
            query := 'CREATE TABLE "customer_' || substring(NEW.name,1,1) || 
            '"( CONSTRAINT "customer_' || substring(NEW.name,1,1) ||'_name_check" CHECK (lower(substring(name, 1, 1)) = ''' || substring(NEW.name,1,1) || '''::text)
            ) INHERITS (customer); CREATE INDEX "i_customer_' || substring(NEW.name,1,1) ||'_name" ON customer_' || substring(NEW.name,1,1) ||' USING btree(name);';
            EXECUTE query;

            query := 'INSERT INTO customer_' || substring(NEW.name,1,1) || ' VALUES(' || NEW.id || ','''|| NEW.name||''')';
            EXECUTE query;

            query := 'ANALYZE "customer_' || substring(NEW.name,1,1) || '"';
            EXECUTE query;

            RETURN NULL;

end;
$BODY$
  LANGUAGE plpgsql VOLATILE STRICT
  COST 100;

CREATE TRIGGER t_customer
  BEFORE INSERT OR UPDATE OR DELETE
  ON customer
  FOR EACH ROW
  EXECUTE PROCEDURE test_trigger();

CREATE TABLE customer
(
  id bigserial NOT NULL,
  name text,
  datecreated timestamp with time zone DEFAULT now(),
  CONSTRAINT customer_pkey PRIMARY KEY (id) USING INDEX TABLESPACE pg_default
);

CREATE OR REPLACE FUNCTION test_trigger()
  RETURNS trigger AS
$BODY$
declare
    query   text;
begin
    query := 'INSERT INTO customer_' || substring(NEW.name,1,1) || ' VALUES(' || NEW.id || ','''|| NEW.name||''')';
    EXECUTE query;

    RETURN NULL;

    EXCEPTION
        WHEN undefined_table THEN
            query := 'CREATE TABLE "customer_' || substring(NEW.name,1,1) || 
            '"( CONSTRAINT "customer_' || substring(NEW.name,1,1) ||'_name_check" CHECK (lower(substring(name, 1, 1)) = ''' || substring(NEW.name,1,1) || '''::text)
            ) INHERITS (customer); CREATE INDEX "i_customer_' || substring(NEW.name,1,1) ||'_name" ON customer_' || substring(NEW.name,1,1) ||' USING btree(name);';
            EXECUTE query;

            query := 'INSERT INTO customer_' || substring(NEW.name,1,1) || ' VALUES(' || NEW.id || ','''|| NEW.name||''')';
            EXECUTE query;

            query := 'ANALYZE "customer_' || substring(NEW.name,1,1) || '"';
            EXECUTE query;

            RETURN NULL;

end;
$BODY$
  LANGUAGE plpgsql VOLATILE STRICT
  COST 100;

CREATE TRIGGER t_customer
  BEFORE INSERT OR UPDATE OR DELETE
  ON customer
  FOR EACH ROW
  EXECUTE PROCEDURE test_trigger();

INSERT INTO customer(name) VALUES ('john'), ('peter');
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