--調用索引idx_cc select count(*),aa,bb From test_tab where cc='a' group by aa,bb --調用索引idx_aa select count(*),cc From test_tab where aa='aa' and bb='bb' group by cc --調用索引idx_aa select count(*),cc From test_tab where aa='aa' group by cc --調用索引idx_aa select count(*),cc From test_tab where bb='bb' group by cc
select count(*),aa,bb From test_tab where cc='a' group by aa,bb
--調用索引idx_aa
select count(*),cc From test_tab where aa='aa' and bb='bb' group by cc
--調用索引idx_aa
select count(*),cc From test_tab where aa='aa' group by cc
--調用索引idx_aa
select count(*),cc From test_tab where bb='bb' group by cc