-- -- SELECT_HAVING -- -- load test data CREATE TABLE test_having (a int, b int, c char(8), d char); INSERT INTO test_having VALUES (0, 1, 'XXXX', 'A'); INSERT INTO test_having VALUES (1, 2, 'AAAA', 'b'); INSERT INTO test_having VALUES (2, 2, 'AAAA', 'c'); INSERT INTO test_having VALUES (3, 3, 'BBBB', 'D'); INSERT INTO test_having VALUES (4, 3, 'BBBB', 'e'); INSERT INTO test_having VALUES (5, 3, 'bbbb', 'F'); INSERT INTO test_having VALUES (6, 4, 'cccc', 'g'); INSERT INTO test_having VALUES (7, 4, 'cccc', 'h'); INSERT INTO test_having VALUES (8, 4, 'CCCC', 'I'); INSERT INTO test_having VALUES (9, 4, 'CCCC', 'j'); SELECT b, c FROM test_having GROUP BY b, c HAVING count(*) = 1; b | c ---+---------- 1 | XXXX 3 | bbbb (2 rows) SELECT lower(c), count(c) FROM test_having GROUP BY lower(c) HAVING count(*) > 2 OR min(a) = max(a); lower | count ----------+------- bbbb | 3 cccc | 4 xxxx | 1 (3 rows) SELECT c, max(a) FROM test_having GROUP BY c HAVING count(*) > 2 OR min(a) = max(a); c | max ----------+----- bbbb | 5 XXXX | 0 (2 rows) DROP TABLE test_having;