Hello, The following SQL demonstrates a crash in the backend. It occurs in both the current Debian Linux 7.0.2 package, and in a separately compiled version of the same. --8<-- CREATE TABLE A ( A INT4, B INT4, C INT4 ); CREATE TABLE B ( A INT4, B INT4, C INT4 ); CREATE TABLE C ( A INT4, B INT4, C INT4 ); /* The inserts are optional, but demonstrate that the first two queries * produce correct results. */ INSERT INTO A VALUES (1,2,3); INSERT INTO A VALUES (1,2,5); INSERT INTO B VALUES (1,2,3); INSERT INTO B VALUES (1,2,5); INSERT INTO B VALUES (1,2,6); INSERT INTO C VALUES (1,2,4); /* This runs OK */ SELECT * FROM A,B,C WHERE A.A = B.A AND A.B = B.B AND A.C = B.C AND B.A = C.A AND B.B = C.B; /* As does this */ SELECT * FROM A JOIN B ON (A.A = B.A AND A.B = B.B AND A.C = B.C) JOIN C ON (B.A = C.A AND B.B = C.B); /* * This makes the backend close the channel unexpectedly (die), * but should be equivalent to the example using ON. */ SELECT * FROM A JOIN B USING (A,B,C) JOIN C USING (A,B); --8<-- Regards, Chris