On Tue, Aug 23, 2005 at 10:30:14AM -0400, Emi Lu wrote: > I'd like to setup foreign key constraint for A.col3, as the following: > CONSTRAINT Aclo3_fk FOREIGN KEY (col3) REFERENCES B(colB1) > > But I got a warning msg from postgresql as: > > foreign key constraint "Aclo3_fk" will require costly sequential scans Is there not a DETAIL message following this warning? It should explain the problem: the referring and the referred-to columns are of different types. Additionally, it's usually a good idea to create an index on the referring column (A.col3) to speed up referential integrity checks when modifying the referred-to table (B). -- Michael Fuhr ---------------------------(end of broadcast)--------------------------- TIP 5: don't forget to increase your free space map settings
