Table inherit & foreign key problem

Hi all,

i have problems with tables an foreign keys. i created the following
tables: (i did not copy all the command, only the important (in my point of view)
CREATE TABLE element (   id bigint NOT NULL,   site_id bigint,   type_id bigint NOT NULL,   name character
varying(512),  description text,   active boolean NOT NULL
 
);

CREATE TABLE crmuser (   username character varying(32) NOT NULL,   firstname character varying(64),   lastname
charactervarying(64)
 
)
INHERITS (element);

CREATE TABLE "comment" (   user_id bigint,   created timestamp without time zone,   content text,   element_id bigint
NOTNULL
 
)
INHERITS (element);



CREATE INDEX idx_comment_id ON "comment" USING btree (id);

CREATE INDEX idx_comment_user_id ON "comment" USING btree (user_id);

CREATE INDEX idx_comment_element_id ON "comment" USING btree (element_id);

ALTER TABLE ONLY element   ADD CONSTRAINT element_pkey PRIMARY KEY (id);

ALTER TABLE ONLY crmuser   ADD CONSTRAINT crmuser_pkey PRIMARY KEY (id);


ALTER TABLE ONLY "comment"   ADD CONSTRAINT comment_pkey PRIMARY KEY (id);

ALTER TABLE ONLY "comment"   ADD CONSTRAINT "$3" FOREIGN KEY (user_id) REFERENCES crmuser(id);

ALTER TABLE ONLY "comment"   ADD CONSTRAINT "$4" FOREIGN KEY (element_id) REFERENCES element(id);    




when i try to insert an comment with element_id = id of an user which is
visible when i call "select * from element", i get an foreign key
violation error: element_id=XY is not available in element.

i would like to reference to the element table, because i have some
tables which inherit from element and i would like to add comments to
these elements.

is this impossible or did i do a silly mistake? i did not find a
solution unsing google.


- Moritz




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