--disable_abort_on_errror # let $FLOAT_VAL= 1.175494345e-38; # good let $FLOAT_VAL= 1.175494345e-14; # bad let $FLOAT_VAL= 1.175494345e-15; let $FLOAT_VAL= 1.175494345e-15; CREATE TABLE t3 LIKE t1; CREATE TABLE t4 LIKE t1; eval INSERT INTO t1 SET f1 = $FLOAT_VAL, mysql_version = VERSION(); eval INSERT INTO t2 SET f1 = $FLOAT_VAL, mysql_version = VERSION(); eval INSERT INTO t3 SET f1 = $FLOAT_VAL, mysql_version = VERSION(); eval INSERT INTO t4 SET f1 = $FLOAT_VAL, mysql_version = VERSION(); SELECT pk, f1, mysql_version FROM t1; SELECT pk, f1, mysql_version FROM t2; SELECT pk, f1, mysql_version FROM t3; SELECT pk, f1, mysql_version FROM t4; # Select via WHERE f1 = eval SELECT f1, pk, mysql_version FROM t1 WHERE f1 = $FLOAT_VAL; eval SELECT f1, pk, mysql_version FROM t2 WHERE f1 = $FLOAT_VAL; eval SELECT f1, pk, mysql_version FROM t3 WHERE f1 = $FLOAT_VAL; eval SELECT f1, pk, mysql_version FROM t4 WHERE f1 = $FLOAT_VAL; # Join in "Universe created with 4.1 history" SELECT A.f1, A.pk, A.mysql_version, B.pk, B.mysql_version FROM t1 A,t2 B WHERE A.f1 = B.f1; # Join in "Universe created with 5.0 history" SELECT A.f1, A.pk, A.mysql_version, B.pk, B.mysql_version FROM t3 A,t4 B WHERE A.f1 = B.f1; # Join between the "Universes" SELECT A.f1, A.pk, A.mysql_version, B.pk, B.mysql_version FROM t1 A,t3 B WHERE A.f1 = B.f1; SELECT A.f1 - B.f1 AS difference, A.mysql_version, B.mysql_version FROM t1 A,t3 B WHERE A.pk = B.pk;