oracle，sql，触发器

Question

CREATE TRIGGER "CPI"."TRGPRODOFFRPRICE" 
AFTER UPDATE or INSERT ON CPI_LOADER_EXEMPTIONS
FOR EACH ROW
DECLARE
table_name varchar(32);
BEGIN
 if substr(:new.SID_ID,1,3) = 'POP' then
  table_name := 'PROD_OFFR_PRICE_CHARGE';
 else 
  table_name := 'PROD_OFFR_PRICE_ALTERATION';
 end if;
 execute immediate 'UPDATE  :1 set CPI_EXEMPTION=:2 WHERE SID_ID=:3'   using table_name, :new.FLAG, :new.SID_ID;
END;

Based on comments i edited into this form, which looks better, but when trying to insert value into table which launches trigger i am getting error 'invalid table name', any idea what is causing this ? wrong tab var declaration possibly?

Answer 1

Try this (real PL/SQL):

CREATE TRIGGER trgSample
AFTER UPDATE or INSERT ON EXEMPTIONS
FOR EACH ROW
DECLARE
   sid varchar(10);
   sidVal varchar(100);
   table_name varchar(32);
   flag int;
BEGIN
  sid   := substr(:new.SID_ID,1,3);
  flag  := :new.FLAG;
  sidVal := :new.SID_ID;
  if sid = 'POP' then
    table_name := 'PROD_VAL';
  else 
    table_name := 'PROD_VAL2';
  end if;
  execute immediate 'UPDATE ' || table_name 
                    || ' set EXEMPTION=sidVal WHERE SID_ID=:x' using sidVal;
END;

Answer 2

AFter all only these changes were neccessary: 'change var to varchar2 for table_name:' only slight update on execute statement: 'execute immediate 'UPDATE :1 set CPI_EXEMPTION=:2 WHERE SID_ID=:3' using table_name, :new.FLAG, :new.SID_ID;'

thanks for all comments, they ´ve helped me a lot. And need to say ai learn a lot.