At 2026-01-19 17:09:54, "jian he" <[email protected]> wrote: >hi. > >CREATE FUNCTION dummy_trigger() RETURNS TRIGGER AS $$ > BEGIN > RETURN NULL; > END >$$ language plpgsql; > >create table main_table(a int); >CREATE TRIGGER before_ins_stmt_trig BEFORE INSERT ON main_table >FOR EACH ROW >WHEN (new.a > 0) >EXECUTE PROCEDURE dummy_trigger(); > >ALTER TABLE main_table ALTER COLUMN a SET DATA TYPE INT8; --error >ALTER TABLE main_table DROP COLUMN a; --error > >Dropping a column or changing its data type will fail if the column is >referenced in a trigger’s WHEN clause, that's the current behavior. >I think we should expand that to a whole-row reference WHEN clause in trigger. > >DROP TRIGGER before_ins_stmt_trig ON main_table; >CREATE TRIGGER before_ins_stmt_trig BEFORE INSERT ON main_table >FOR EACH ROW >WHEN (new is null) >EXECUTE PROCEDURE dummy_trigger(); >ALTER TABLE main_table ALTER COLUMN a SET DATA TYPE INT8; --expect to error >ALTER TABLE main_table DROP COLUMN a; --expect to error > >new summary: >For (constraints, indexes, policies, triggers) that contain whole-row >references: >ALTER TABLE DROP COLUMN [CASCADE] will drop these objects too. > >ALTER COLUMN SET DATA TYPE will error out because whole-row–dependent objects >exist. > >
Hello, I did take a look at v7-0001 and v7-0002. In v7-0002: 1. > + pull_varattnos(expr, PRS2_OLD_VARNO, &expr_attrs); > + pull_varattnos(expr, PRS2_NEW_VARNO, &expr_attrs); The function "pull_varattnos" was called twice, with different varno parameters each time (first using PRS2_NEW_VARNO, then using PRS2_OLD_VARNO). I think it would be better to use PRS2_NEW_VARNO | PRS2_OLD_VARNO in a single call. pull_varattnos(expr, PRS2_NEW_VARNO | PRS2_OLD_VARNO, &expr_attrs); 2. > + if (trig->tgqual != NULL) Should we first check if TRIGGER_FOR_ROW(trig->tgtype) before processing trig->tgqual are more appropriate? 3. Another issue is the Bitmapset set allocated by pull_varattnos will never be released. This will cause a memory leak. Please add the statement bms_free(expr_attrs); after each usage within the loops in recordWholeRowDependencyOnOrError. In v7-0001： As in v7-0002, the Bitmapset returned by pull_varattnos is never released. Please add the statement bms_free(expr_attrs); Regards, Jinbinge
