ORA-02291 Error on delete with cascade

Question

Hello guys! I have a mastertable called TBL_VEG_MAINDATA (PK cnt_veg_maindata) and a subtable TBL_VEG_SUBDATA, which references the parent pk column using a foreign key. The foreign key is set to cascade on delete. Hence when I delete a parent entry, all related datsets in my subtable should be automatically deleted as well. Nevertheless, whenever I delete a parent record from TBL_VEG_MAINDATA, I stumble upon an integrity constraint (parent key not found).
In fact I expect the rdbms to automatically forward the delete request to the subtable when the parent dataset is deleted.
Do you have an idea what I am doing wrong?
A million thanks in advance!
Brgds,
Seb

Answer 1

Hi SBH!
Thanks for your answer! I posted the complete table definitions below, including constraints and triggers in order to avoid missing anything!
I have no clue as to why it doesn't work in this case. Never had this problem before.
CREATE TABLE  "TBL_VEG_MAINDATA"
   (     "CNT_VEG_MAINDATA" NUMBER NOT NULL ENABLE,
     "LNG_GEBIET" VARCHAR2(10 CHAR) NOT NULL ENABLE,
     "STR_LRT_CLASS" VARCHAR2(8 CHAR) NOT NULL ENABLE,
     "INT_BEARBEITER" NUMBER(3,0),
     "INT_SEALEVEL" NUMBER(4,0),
     "STR_EXPOSITION" VARCHAR2(2 CHAR),
     "INT_INKLINATION" NUMBER(8,0),
     "STR_COMMENT" VARCHAR2(255 CHAR),
     "INT_VEG_RECORD" NUMBER(2,0) NOT NULL ENABLE,
     "DATE_SAVEDATE" DATE,
     "INT_TK" NUMBER(8,0),
     "INT_R" NUMBER(8,0),
     "INT_H" NUMBER(8,0),
     "INT_FLAECHE" NUMBER(5,2),
     "STR_COVERAGE_COMMENT" VARCHAR2(255 CHAR),
     "STR_VERFAHREN" VARCHAR2(3),
      CONSTRAINT "TBL_VEG_MAINDATA_PK" PRIMARY KEY ("CNT_VEG_MAINDATA") ENABLE,
      CONSTRAINT "CON_UQ_TBL_VEG_MAINDATA" UNIQUE ("LNG_GEBIET", "STR_LRT_CLASS", "INT_VEG_RECORD", "STR_VERFAHREN") ENABLE
ALTER TABLE  "TBL_VEG_MAINDATA" ADD CONSTRAINT "CON_FK_TBL_MAINDATA" FOREIGN KEY ("LNG_GEBIET")
       REFERENCES  "TBL_GEBIET" ("CNT_GEBIET") ON DELETE CASCADE ENABLE
CREATE INDEX  "IDX1_TBL_VEG_MAINDATA" ON  "TBL_VEG_MAINDATA" ("LNG_GEBIET", "STR_LRT_CLASS")
CREATE INDEX  "IDX2_VEG_MAINDATA" ON  "TBL_VEG_MAINDATA" ("INT_BEARBEITER", "INT_SEALEVEL", "STR_EXPOSITION", "INT_INKLINATION")
CREATE OR REPLACE TRIGGER  "TR_IN_TBL_VEG_MAINDATA"
  before insert on "TBL_VEG_MAINDATA"             
  for each row
begin 
  if :new."CNT_VEG_MAINDATA" is null then
    select "SEQ_TBL_VEG_MAIN".nextval into :new."CNT_VEG_MAINDATA" from dual;
  end if;
end;and for th subtable
CREATE TABLE  "TBL_VEG_SUBDATA"
   (     "CNT_VEG_SUBDATA" NUMBER NOT NULL ENABLE,
     "INT_VEG_ART" NUMBER(4,0),
     "LNG_VEG_MAINDATA" NUMBER(10,0) NOT NULL ENABLE,
     "INT_DECKUNGSGRAD" NUMBER(1,0),
      CONSTRAINT "TBL_VEG_SUBDATA_PK" PRIMARY KEY ("CNT_VEG_SUBDATA") ENABLE
ALTER TABLE  "TBL_VEG_SUBDATA" ADD CONSTRAINT "CON_FK_TBL_VEG_SUBDATA" FOREIGN KEY ("LNG_VEG_MAINDATA")
       REFERENCES  "TBL_VEG_MAINDATA" ("CNT_VEG_MAINDATA") ON DELETE CASCADE ENABLE
CREATE OR REPLACE TRIGGER  "TR_IN_TBL_VEG_SUBDATA"
  before insert on "TBL_VEG_SUBDATA"             
  for each row
begin 
  if :new."CNT_VEG_SUBDATA" is null then
    select "SEQ_TBL_VEG_SUBDATA".nextval into :new."CNT_VEG_SUBDATA" from dual;
  end if;
end;
/Maybe you'll I see soemthing I missed...
Thanks for your effort.
Rgds,
Seb