# # Test of cost calculations. This test is using the Aria engine as the cost # calculations are stable for it. # # This file also includes MDEV's that shows errors in cost calculation functions. # --source include/have_sequence.inc --source include/have_innodb.inc create table t1 (a int primary key, b int, c int, d int, e int, key ba (b,a), key bda (b,d,a), key cba (c,b,a), key cb (c,b), key d (d)) engine=aria; insert into t1 select seq,seq,seq,seq,seq from seq_1_to_10; insert into t1 values(20,2,2,2,2),(21,3,4,5,6); --echo # --echo # Get different scan costs --echo # explain select sum(e) as "table_scan" from t1; --source include/last_query_cost.inc explain select sum(a) as "index scan" from t1; --source include/last_query_cost.inc --echo # --echo # Range scans should be used if we don't examine all rows in the table --echo # explain select count(a) from t1; --source include/last_query_cost.inc explain select count(*) from t1 where a > 0; --source include/last_query_cost.inc explain select count(*) from t1 where a > 1; --source include/last_query_cost.inc explain select count(*) from t1 where a > 2; --source include/last_query_cost.inc --echo # --echo # Shorter indexes are prefered over longer indexs --echo # explain select sum(a+b) from t1; --source include/last_query_cost.inc explain select count(*) from t1 where b between 5 and 10; --source include/last_query_cost.inc explain select sum(b+c) from t1 where b between 5 and 6 and c between 5 and 6; --source include/last_query_cost.inc --echo # Cost of 'd' should be slightly smaller as key 'ba' is longer than 'd' explain select count(*) from t1 where b > 6; --source include/last_query_cost.inc explain select count(*) from t1 where d > 6; --source include/last_query_cost.inc --echo # --echo # Check covering index usage --echo # explain select a,b,c from t1 where a=b; --source include/last_query_cost.inc --echo # --echo # Prefer ref keys over ranges --echo # explain select count(*) from t1 where b=2; --source include/last_query_cost.inc explain select count(*) from t1 where b=2 and c=2; --source include/last_query_cost.inc explain select count(*) from t1 where b=3 and c between 3 and 4; --source include/last_query_cost.inc --echo # --echo # Prefer eq keys over ref keys --echo # explain select a,b,e from t1 where a=10 or a=11; --source include/last_query_cost.inc explain select a,b,e from t1 where d=10 or d=11; --source include/last_query_cost.inc drop table t1; --echo # --echo # MDEV-30328 Assertion `avg_io_cost != 0.0 || index_cost.io + row_cost.io == 0' failed in --echo # Cost_estimate::total_cost() --echo # set @save=@@InnoDB.optimizer_disk_read_ratio; set global InnoDB.optimizer_disk_read_ratio=0; create table t1 ( `l_orderkey` int(11) NOT NULL, `l_partkey` int(11) DEFAULT NULL, `l_suppkey` int(11) DEFAULT NULL, `l_linenumber` int(11) NOT NULL, `l_extra` int(11) NOT NULL, `l_quantity` double DEFAULT NULL, `l_extendedprice` double DEFAULT NULL, `l_discount` double DEFAULT NULL, `l_tax` double DEFAULT NULL, `l_returnflag` char(1) DEFAULT NULL, `l_linestatus` char(1) DEFAULT NULL, `l_shipDATE` date DEFAULT NULL, `l_commitDATE` date DEFAULT NULL, `l_receiptDATE` date DEFAULT NULL, `l_shipinstruct` char(25) DEFAULT NULL, `l_shipmode` char(10) DEFAULT NULL, `l_comment` varchar(44) DEFAULT NULL, PRIMARY KEY (`l_orderkey`), UNIQUE (`l_linenumber`), UNIQUE (`l_extra`) , KEY `l_suppkey` (l_suppkey, l_partkey), KEY `long_suppkey` (l_partkey, l_suppkey, l_linenumber, l_extra) ) ENGINE= InnoDB; explain select count(*) from test.t1 force index (l_suppkey) where l_suppkey >= 0 and l_partkey >=0; drop table t1; set global InnoDB.optimizer_disk_read_ratio=@save;