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0a7d291756
The assert was there to check that engines reports sensible numbers for IO. However this does not work in case of optimizer_disk_read_ratio=0. Fixed by removing the assert.
126 lines
5.2 KiB
Text
126 lines
5.2 KiB
Text
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;
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insert into t1 select seq,seq,seq,seq,seq from seq_1_to_10;
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insert into t1 values(20,2,2,2,2),(21,3,4,5,6);
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#
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# Get different scan costs
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#
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explain select sum(e) as "table_scan" from t1;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 ALL NULL NULL NULL NULL 12
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Last_query_cost 0.012556
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explain select sum(a) as "index scan" from t1;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 index NULL PRIMARY 4 NULL 12 Using index
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Last_query_cost 0.007441
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#
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# Range scans should be used if we don't examine all rows in the table
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#
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explain select count(a) from t1;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE NULL NULL NULL NULL NULL NULL NULL Select tables optimized away
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Last_query_cost 0.000000
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explain select count(*) from t1 where a > 0;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 range PRIMARY PRIMARY 4 NULL 12 Using where; Using index
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Last_query_cost 0.002877
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explain select count(*) from t1 where a > 1;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 range PRIMARY PRIMARY 4 NULL 12 Using where; Using index
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Last_query_cost 0.002877
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explain select count(*) from t1 where a > 2;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 range PRIMARY PRIMARY 4 NULL 11 Using where; Using index
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Last_query_cost 0.002747
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#
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# Shorter indexes are prefered over longer indexs
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#
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explain select sum(a+b) from t1;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 index NULL ba 9 NULL 12 Using index
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Last_query_cost 0.007441
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explain select count(*) from t1 where b between 5 and 10;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 range ba,bda ba 5 NULL 6 Using where; Using index
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Last_query_cost 0.002097
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explain select sum(b+c) from t1 where b between 5 and 6 and c between 5 and 6;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 range ba,bda,cba,cb cba 10 NULL 2 Using where; Using index
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Last_query_cost 0.001577
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# Cost of 'd' should be slightly smaller as key 'ba' is longer than 'd'
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explain select count(*) from t1 where b > 6;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 range ba,bda ba 5 NULL 5 Using where; Using index
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Last_query_cost 0.001967
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explain select count(*) from t1 where d > 6;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 range d d 5 NULL 5 Using where; Using index
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Last_query_cost 0.001967
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#
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# Check covering index usage
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#
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explain select a,b,c from t1 where a=b;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 index NULL cba 14 NULL 12 Using where; Using index
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Last_query_cost 0.007441
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#
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# Prefer ref keys over ranges
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#
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explain select count(*) from t1 where b=2;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 ref ba,bda ba 5 const 2 Using index
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Last_query_cost 0.001141
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explain select count(*) from t1 where b=2 and c=2;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 ref ba,bda,cba,cb cba 10 const,const 2 Using index
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Last_query_cost 0.001141
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explain select count(*) from t1 where b=3 and c between 3 and 4;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 range ba,bda,cba,cb cba 10 NULL 2 Using where; Using index
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Last_query_cost 0.001577
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#
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# Prefer eq keys over ref keys
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#
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explain select a,b,e from t1 where a=10 or a=11;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 range PRIMARY PRIMARY 4 NULL 2 Using index condition
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Last_query_cost 0.003126
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explain select a,b,e from t1 where d=10 or d=11;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 range d d 5 NULL 2 Using index condition
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Last_query_cost 0.003291
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drop table t1;
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#
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# MDEV-30328 Assertion `avg_io_cost != 0.0 || index_cost.io + row_cost.io == 0' failed in
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# Cost_estimate::total_cost()
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#
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set @save=@@InnoDB.optimizer_disk_read_ratio;
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set global InnoDB.optimizer_disk_read_ratio=0;
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create table t1 (
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`l_orderkey` int(11) NOT NULL,
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`l_partkey` int(11) DEFAULT NULL,
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`l_suppkey` int(11) DEFAULT NULL,
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`l_linenumber` int(11) NOT NULL,
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`l_extra` int(11) NOT NULL,
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`l_quantity` double DEFAULT NULL,
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`l_extendedprice` double DEFAULT NULL,
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`l_discount` double DEFAULT NULL,
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`l_tax` double DEFAULT NULL,
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`l_returnflag` char(1) DEFAULT NULL,
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`l_linestatus` char(1) DEFAULT NULL,
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`l_shipDATE` date DEFAULT NULL,
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`l_commitDATE` date DEFAULT NULL,
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`l_receiptDATE` date DEFAULT NULL,
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`l_shipinstruct` char(25) DEFAULT NULL,
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`l_shipmode` char(10) DEFAULT NULL,
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`l_comment` varchar(44) DEFAULT NULL,
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PRIMARY KEY (`l_orderkey`),
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UNIQUE (`l_linenumber`),
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UNIQUE (`l_extra`) ,
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KEY `l_suppkey` (l_suppkey, l_partkey),
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KEY `long_suppkey` (l_partkey, l_suppkey, l_linenumber, l_extra) )
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ENGINE= InnoDB;
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explain select count(*) from test.t1 force index (l_suppkey) where l_suppkey >= 0 and l_partkey >=0;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 range l_suppkey l_suppkey 10 NULL 1 Using where; Using index
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drop table t1;
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set global InnoDB.optimizer_disk_read_ratio=@save;
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