Hi, Why the query below doesn't use the indexes ? 1 index on FORMID, FORMINDEX, SUBJECTID, VISITID on the each tables. Thanks for your lights. Oracle 9.2.0.7 p97> SELECT * FROM 2 CL318886012_ECRF_DW.T_SUBJECTV ISITFORM A, 3 CL318886012_ECRF_DW.T_CUR_QUER Y B, 4 CL318886012_ECRF_DW.T_EVENT_IC LD C
