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Commit 87d4d723 authored by Monty's avatar Monty Committed by Sergei Petrunia
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Limit calculated rows to the number of rows in the table 

The result file changes are mainly that number of rows is one smaller
for some queries with DISTINCT or GROUP BY
parent c443dbff
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Showing with 43 additions and 37 deletions
mysql-test/main/distinct.result
View file @ 87d4d723
......@@ -538,10 +538,10 @@ PRIMARY KEY (a,b));
INSERT INTO t2 VALUES (1,1,1,50), (1,2,3,40), (2,1,3,4);
EXPLAIN SELECT DISTINCT a FROM t2;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t2 range NULL PRIMARY 4 NULL 4 Using index for group-by
1 SIMPLE t2 range NULL PRIMARY 4 NULL 3 Using index for group-by
EXPLAIN SELECT DISTINCT a,a FROM t2;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t2 range NULL PRIMARY 4 NULL 4 Using index for group-by
1 SIMPLE t2 range NULL PRIMARY 4 NULL 3 Using index for group-by
EXPLAIN SELECT DISTINCT b,a FROM t2;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t2 index NULL PRIMARY 8 NULL 3 Using index
......@@ -756,7 +756,7 @@ INSERT INTO t1(a, b, c) VALUES (1, 1, 1),
(1, 2, 3);
EXPLAIN SELECT DISTINCT a, b, d, c FROM t1;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range NULL PRIMARY 16 NULL 7 Using index for group-by; Using temporary
1 SIMPLE t1 range NULL PRIMARY 16 NULL 6 Using index for group-by; Using temporary
SELECT DISTINCT a, b, d, c FROM t1;
a b d c
1 1 0 1
......
mysql-test/main/explain_innodb.result
View file @ 87d4d723
......@@ -15,6 +15,6 @@ explain
SELECT * FROM (SELECT id FROM t1 GROUP BY id) dt WHERE 1=0;
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY NULL NULL NULL NULL NULL NULL NULL Impossible WHERE
2 DERIVED t1 range NULL id 53 NULL 2 Using index for group-by
2 DERIVED t1 range NULL id 53 NULL 1 Using index for group-by
SET GLOBAL slow_query_log = @sql_tmp;
drop table t1;
mysql-test/main/group_by.result
View file @ 87d4d723
......@@ -1578,7 +1578,7 @@ id select_type table type possible_keys key key_len ref rows Extra
EXPLAIN SELECT a FROM t1 FORCE INDEX FOR JOIN (i2)
FORCE INDEX FOR GROUP BY (i2) GROUP BY a;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range NULL i2 4 NULL 145 Using index for group-by
1 SIMPLE t1 range NULL i2 4 NULL 144 Using index for group-by
EXPLAIN SELECT a FROM t1 USE INDEX () IGNORE INDEX (i2);
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 144
......@@ -1701,7 +1701,7 @@ NULL 1
1 2
EXPLAIN SELECT a from t2 GROUP BY a;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t2 range NULL a 5 NULL 7 Using index for group-by
1 SIMPLE t2 range NULL a 5 NULL 6 Using index for group-by
SELECT a from t2 GROUP BY a;
a
NULL
......
mysql-test/main/group_min_max.result
View file @ 87d4d723
......@@ -3664,7 +3664,7 @@ f1 COUNT(DISTINCT f2)
3 4
explain SELECT f1, COUNT(DISTINCT f2) FROM t1 GROUP BY f1;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range NULL f1 5 NULL 9 Using index for group-by
1 SIMPLE t1 range NULL f1 5 NULL 8 Using index for group-by
drop table t1;
# End of test#50539.
#
......
mysql-test/main/opt_trace.result
View file @ 87d4d723
......@@ -1408,7 +1408,7 @@ test.t1 analyze status Engine-independent statistics collected
test.t1 analyze status OK
EXPLAIN SELECT MIN(d) FROM t1 where b=2 and c=3 group by a;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range NULL a 20 NULL 8 Using where; Using index for group-by
1 SIMPLE t1 range NULL a 20 NULL 7 Using where; Using index for group-by
select * from information_schema.OPTIMIZER_TRACE;
QUERY TRACE MISSING_BYTES_BEYOND_MAX_MEM_SIZE INSUFFICIENT_PRIVILEGES
EXPLAIN SELECT MIN(d) FROM t1 where b=2 and c=3 group by a {
......@@ -1495,8 +1495,8 @@ EXPLAIN SELECT MIN(d) FROM t1 where b=2 and c=3 group by a {
"index": "a",
"covering": true,
"ranges": ["(2,3) <= (b,c) <= (2,3)"],
"rows": 8,
"cost": 2.2
"rows": 7,
"cost": 2.05
}
]
},
......@@ -1507,8 +1507,8 @@ EXPLAIN SELECT MIN(d) FROM t1 where b=2 and c=3 group by a {
"min_aggregate": true,
"max_aggregate": false,
"distinct_aggregate": false,
"rows": 8,
"cost": 2.2,
"rows": 7,
"cost": 2.05,
"key_parts_used_for_access": ["a", "b", "c"],
"ranges": ["(2,3) <= (b,c) <= (2,3)"],
"chosen": true
......@@ -1521,13 +1521,13 @@ EXPLAIN SELECT MIN(d) FROM t1 where b=2 and c=3 group by a {
"min_aggregate": true,
"max_aggregate": false,
"distinct_aggregate": false,
"rows": 8,
"cost": 2.2,
"rows": 7,
"cost": 2.05,
"key_parts_used_for_access": ["a", "b", "c"],
"ranges": ["(2,3) <= (b,c) <= (2,3)"]
},
"rows_for_plan": 8,
"cost_for_plan": 2.2,
"rows_for_plan": 7,
"cost_for_plan": 2.05,
"chosen": true
}
}
......@@ -1545,16 +1545,16 @@ EXPLAIN SELECT MIN(d) FROM t1 where b=2 and c=3 group by a {
"considered_access_paths": [
{
"access_type": "index_merge",
"resulting_rows": 8,
"cost": 2.2,
"resulting_rows": 7,
"cost": 2.05,
"chosen": true,
"use_tmp_table": true
}
],
"chosen_access_method": {
"type": "index_merge",
"records": 8,
"cost": 2.2,
"records": 7,
"cost": 2.05,
"uses_join_buffering": false
}
}
......@@ -1564,9 +1564,9 @@ EXPLAIN SELECT MIN(d) FROM t1 where b=2 and c=3 group by a {
{
"plan_prefix": [],
"table": "t1",
"rows_for_plan": 8,
"cost_for_plan": 3.8,
"cost_for_sorting": 8
"rows_for_plan": 7,
"cost_for_plan": 3.45,
"cost_for_sorting": 7
}
]
},
......
mysql-test/main/subselect_mat.result
View file @ 87d4d723
......@@ -1142,7 +1142,7 @@ a
explain extended
select a from t1 group by a having a in (select c from t2 where d >= 20);
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1 range NULL it1a 4 NULL 8 100.00 Using index for group-by
1 PRIMARY t1 range NULL it1a 4 NULL 7 100.00 Using index for group-by
2 MATERIALIZED t2 ALL NULL NULL NULL NULL 7 100.00 Using where
Warnings:
Note 1003 /* select#1 */ select `test`.`t1`.`a` AS `a` from `test`.`t1` group by `test`.`t1`.`a` having <expr_cache><`test`.`t1`.`a`>(<in_optimizer>(`test`.`t1`.`a`,`test`.`t1`.`a` in ( <materialize> (/* select#2 */ select `test`.`t2`.`c` from `test`.`t2` where `test`.`t2`.`d` >= 20 ), <primary_index_lookup>(`test`.`t1`.`a` in <temporary table> on distinct_key where `test`.`t1`.`a` = `<subquery2>`.`c`))))
......@@ -1154,7 +1154,7 @@ create index iab on t1(a, b);
explain extended
select a from t1 group by a having a in (select c from t2 where d >= 20);
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1 range NULL it1a 4 NULL 8 100.00 Using index for group-by
1 PRIMARY t1 range NULL it1a 4 NULL 7 100.00 Using index for group-by
2 MATERIALIZED t2 ALL NULL NULL NULL NULL 7 100.00 Using where
Warnings:
Note 1003 /* select#1 */ select `test`.`t1`.`a` AS `a` from `test`.`t1` group by `test`.`t1`.`a` having <expr_cache><`test`.`t1`.`a`>(<in_optimizer>(`test`.`t1`.`a`,`test`.`t1`.`a` in ( <materialize> (/* select#2 */ select `test`.`t2`.`c` from `test`.`t2` where `test`.`t2`.`d` >= 20 ), <primary_index_lookup>(`test`.`t1`.`a` in <temporary table> on distinct_key where `test`.`t1`.`a` = `<subquery2>`.`c`))))
......@@ -1166,7 +1166,7 @@ explain extended
select a from t1 group by a
having a in (select c from t2 where d >= some(select e from t3 where max(b)=e));
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1 range NULL iab 4 NULL 8 100.00 Using index for group-by
1 PRIMARY t1 range NULL iab 4 NULL 7 100.00 Using index for group-by
2 DEPENDENT SUBQUERY t2 ALL NULL NULL NULL NULL 7 100.00 Using where
3 DEPENDENT SUBQUERY t3 ALL NULL NULL NULL NULL 4 100.00 Using where
Warnings:
......
mysql-test/main/subselect_sj_mat.result
View file @ 87d4d723
......@@ -1181,7 +1181,7 @@ a
explain extended
select a from t1 group by a having a in (select c from t2 where d >= 20);
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1 range NULL it1a 4 NULL 8 100.00 Using index for group-by
1 PRIMARY t1 range NULL it1a 4 NULL 7 100.00 Using index for group-by
2 MATERIALIZED t2 ALL NULL NULL NULL NULL 7 100.00 Using where
Warnings:
Note 1003 /* select#1 */ select `test`.`t1`.`a` AS `a` from `test`.`t1` group by `test`.`t1`.`a` having <expr_cache><`test`.`t1`.`a`>(<in_optimizer>(`test`.`t1`.`a`,`test`.`t1`.`a` in ( <materialize> (/* select#2 */ select `test`.`t2`.`c` from `test`.`t2` where `test`.`t2`.`d` >= 20 ), <primary_index_lookup>(`test`.`t1`.`a` in <temporary table> on distinct_key where `test`.`t1`.`a` = `<subquery2>`.`c`))))
......@@ -1193,7 +1193,7 @@ create index iab on t1(a, b);
explain extended
select a from t1 group by a having a in (select c from t2 where d >= 20);
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1 range NULL it1a 4 NULL 8 100.00 Using index for group-by
1 PRIMARY t1 range NULL it1a 4 NULL 7 100.00 Using index for group-by
2 MATERIALIZED t2 ALL NULL NULL NULL NULL 7 100.00 Using where
Warnings:
Note 1003 /* select#1 */ select `test`.`t1`.`a` AS `a` from `test`.`t1` group by `test`.`t1`.`a` having <expr_cache><`test`.`t1`.`a`>(<in_optimizer>(`test`.`t1`.`a`,`test`.`t1`.`a` in ( <materialize> (/* select#2 */ select `test`.`t2`.`c` from `test`.`t2` where `test`.`t2`.`d` >= 20 ), <primary_index_lookup>(`test`.`t1`.`a` in <temporary table> on distinct_key where `test`.`t1`.`a` = `<subquery2>`.`c`))))
......@@ -1205,7 +1205,7 @@ explain extended
select a from t1 group by a
having a in (select c from t2 where d >= some(select e from t3 where max(b)=e));
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1 range NULL iab 4 NULL 8 100.00 Using index for group-by
1 PRIMARY t1 range NULL iab 4 NULL 7 100.00 Using index for group-by
2 DEPENDENT SUBQUERY t2 ALL NULL NULL NULL NULL 7 100.00 Using where
3 DEPENDENT SUBQUERY t3 ALL NULL NULL NULL NULL 4 100.00 Using where
Warnings:
......
mysql-test/suite/gcol/r/gcol_select_innodb.result
View file @ 87d4d723
......@@ -146,7 +146,7 @@ count(distinct c)
3
explain select count(distinct c) from t1;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range NULL c 5 NULL 6 Using index for group-by
1 SIMPLE t1 range NULL c 5 NULL 5 Using index for group-by
###
### filesort & range-based utils
###
......
mysql-test/suite/gcol/r/gcol_select_myisam.result
View file @ 87d4d723
......@@ -146,7 +146,7 @@ count(distinct c)
3
explain select count(distinct c) from t1;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range NULL c 5 NULL 6 Using index for group-by
1 SIMPLE t1 range NULL c 5 NULL 5 Using index for group-by
###
### filesort & range-based utils
###
......
mysql-test/suite/vcol/r/vcol_select_innodb.result
View file @ 87d4d723
......@@ -135,7 +135,7 @@ count(distinct c)
3
explain select count(distinct c) from t1;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range NULL c 5 NULL 6 Using index for group-by
1 SIMPLE t1 range NULL c 5 NULL 5 Using index for group-by
###
### filesort & range-based utils
###
......
mysql-test/suite/vcol/r/vcol_select_myisam.result
View file @ 87d4d723
......@@ -133,7 +133,7 @@ count(distinct c)
3
explain select count(distinct c) from t1;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range NULL c 5 NULL 6 Using index for group-by
1 SIMPLE t1 range NULL c 5 NULL 5 Using index for group-by
###
### filesort & range-based utils
###
......
sql/opt_range.cc
View file @ 87d4d723
......@@ -3235,7 +3235,7 @@ double records_in_column_ranges(PARAM *param, uint idx,
SEL_ARG_RANGE_SEQ seq;
KEY_MULTI_RANGE range;
range_seq_t seq_it;
double rows;
double rows, table_records;
Field *field;
uint flags= 0;
double total_rows= 0;
......@@ -3290,13 +3290,17 @@ double records_in_column_ranges(PARAM *param, uint idx,
total_rows= DBL_MAX;
break;
}
total_rows += rows;
total_rows+= rows;
}
if (total_rows == 0)
total_rows= MY_MIN(1, rows2double(param->table->stat_records()));
return total_rows;
}
table_records= rows2double(param->table->stat_records());
if (total_rows > table_records)
DBUG_PRINT("error", ("table_records: %g < total_records: %g",
table_records, total_rows));
return MY_MIN(total_rows, table_records);
}
/*
......@@ -14813,6 +14817,8 @@ void cost_group_min_max(TABLE* table, KEY *index_info, uint used_key_parts,
num_groups= (ha_rows) rint(num_groups * quick_prefix_selectivity);
set_if_bigger(num_groups, 1);
}
/* Ensure we don't have more groups than rows in table */
set_if_smaller(num_groups, table_records);
if (used_key_parts > group_key_parts)
{ /*
......
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