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Post-second-review fixes for the patch that added the code allowing to use

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hash join over equi-join conditions without supporting indexes.
This commit is contained in:
Igor Babaev
2011-01-24 14:54:50 -08:00
parent b251d8a4c8
commit edeeb023bc
3 changed files with 172 additions and 2333 deletions
Download Patch File Download Diff File Expand all files Collapse all files

2360
mysql-test/r/join_cache.result
View File

File diff suppressed because it is too large Load Diff

122
mysql-test/t/join_cache.test
View File

@@ -46,14 +46,16 @@ SELECT City.Name, Country.Name, CountryLanguage.Language
WHERE City.Country=Country.Code AND WHERE City.Country=Country.Code AND
CountryLanguage.Country=Country.Code AND CountryLanguage.Country=Country.Code AND
City.Name LIKE 'L%' AND Country.Population > 3000000 AND City.Name LIKE 'L%' AND Country.Population > 3000000 AND
CountryLanguage.Percentage > 50; CountryLanguage.Percentage > 50 AND
LENGTH(Language) < LENGTH(City.Name) - 2;
SELECT City.Name, Country.Name, CountryLanguage.Language SELECT City.Name, Country.Name, CountryLanguage.Language
FROM City,Country,CountryLanguage FROM City,Country,CountryLanguage
WHERE City.Country=Country.Code AND WHERE City.Country=Country.Code AND
CountryLanguage.Country=Country.Code AND CountryLanguage.Country=Country.Code AND
City.Name LIKE 'L%' AND Country.Population > 3000000 AND City.Name LIKE 'L%' AND Country.Population > 3000000 AND
CountryLanguage.Percentage > 50; CountryLanguage.Percentage > 50 AND
LENGTH(Language) < LENGTH(City.Name) - 2;
set join_cache_level=2; set join_cache_level=2;
show variables like 'join_cache_level'; show variables like 'join_cache_level';
@@ -73,14 +75,16 @@ SELECT City.Name, Country.Name, CountryLanguage.Language
WHERE City.Country=Country.Code AND WHERE City.Country=Country.Code AND
CountryLanguage.Country=Country.Code AND CountryLanguage.Country=Country.Code AND
City.Name LIKE 'L%' AND Country.Population > 3000000 AND City.Name LIKE 'L%' AND Country.Population > 3000000 AND
CountryLanguage.Percentage > 50; CountryLanguage.Percentage > 50 AND
LENGTH(Language) < LENGTH(City.Name) - 2;
SELECT City.Name, Country.Name, CountryLanguage.Language SELECT City.Name, Country.Name, CountryLanguage.Language
FROM City,Country,CountryLanguage FROM City,Country,CountryLanguage
WHERE City.Country=Country.Code AND WHERE City.Country=Country.Code AND
CountryLanguage.Country=Country.Code AND CountryLanguage.Country=Country.Code AND
City.Name LIKE 'L%' AND Country.Population > 3000000 AND City.Name LIKE 'L%' AND Country.Population > 3000000 AND
CountryLanguage.Percentage > 50; CountryLanguage.Percentage > 50 AND
LENGTH(Language) < LENGTH(City.Name) - 2;
set join_cache_level=3; set join_cache_level=3;
show variables like 'join_cache_level'; show variables like 'join_cache_level';
@@ -100,14 +104,18 @@ SELECT City.Name, Country.Name, CountryLanguage.Language
WHERE City.Country=Country.Code AND WHERE City.Country=Country.Code AND
CountryLanguage.Country=Country.Code AND CountryLanguage.Country=Country.Code AND
City.Name LIKE 'L%' AND Country.Population > 3000000 AND City.Name LIKE 'L%' AND Country.Population > 3000000 AND
CountryLanguage.Percentage > 50; CountryLanguage.Percentage > 50 AND
LENGTH(Language) < LENGTH(City.Name) - 2;
SELECT City.Name, Country.Name, CountryLanguage.Language SELECT City.Name, Country.Name, CountryLanguage.Language
FROM City,Country,CountryLanguage FROM City,Country,CountryLanguage
WHERE City.Country=Country.Code AND WHERE City.Country=Country.Code AND
CountryLanguage.Country=Country.Code AND CountryLanguage.Country=Country.Code AND
City.Name LIKE 'L%' AND Country.Population > 3000000 AND City.Name LIKE 'L%' AND Country.Population > 3000000 AND
CountryLanguage.Percentage > 50; CountryLanguage.Percentage > 50 AND
LENGTH(Language) < LENGTH(City.Name) - 2;
set join_cache_level=4; set join_cache_level=4;
show variables like 'join_cache_level'; show variables like 'join_cache_level';
@@ -127,14 +135,16 @@ SELECT City.Name, Country.Name, CountryLanguage.Language
WHERE City.Country=Country.Code AND WHERE City.Country=Country.Code AND
CountryLanguage.Country=Country.Code AND CountryLanguage.Country=Country.Code AND
City.Name LIKE 'L%' AND Country.Population > 3000000 AND City.Name LIKE 'L%' AND Country.Population > 3000000 AND
CountryLanguage.Percentage > 50; CountryLanguage.Percentage > 50 AND
LENGTH(Language) < LENGTH(City.Name) - 2;
SELECT City.Name, Country.Name, CountryLanguage.Language SELECT City.Name, Country.Name, CountryLanguage.Language
FROM City,Country,CountryLanguage FROM City,Country,CountryLanguage
WHERE City.Country=Country.Code AND WHERE City.Country=Country.Code AND
CountryLanguage.Country=Country.Code AND CountryLanguage.Country=Country.Code AND
City.Name LIKE 'L%' AND Country.Population > 3000000 AND City.Name LIKE 'L%' AND Country.Population > 3000000 AND
CountryLanguage.Percentage > 50; CountryLanguage.Percentage > 50 AND
LENGTH(Language) < LENGTH(City.Name) - 2;
set join_cache_level=default; set join_cache_level=default;
@@ -158,14 +168,16 @@ SELECT City.Name, Country.Name, CountryLanguage.Language
WHERE City.Country=Country.Code AND WHERE City.Country=Country.Code AND
CountryLanguage.Country=Country.Code AND CountryLanguage.Country=Country.Code AND
City.Name LIKE 'L%' AND Country.Population > 3000000 AND City.Name LIKE 'L%' AND Country.Population > 3000000 AND
CountryLanguage.Percentage > 50; CountryLanguage.Percentage > 50 AND
LENGTH(Language) < LENGTH(City.Name) - 2;
SELECT City.Name, Country.Name, CountryLanguage.Language SELECT City.Name, Country.Name, CountryLanguage.Language
FROM City,Country,CountryLanguage FROM City,Country,CountryLanguage
WHERE City.Country=Country.Code AND WHERE City.Country=Country.Code AND
CountryLanguage.Country=Country.Code AND CountryLanguage.Country=Country.Code AND
City.Name LIKE 'L%' AND Country.Population > 3000000 AND City.Name LIKE 'L%' AND Country.Population > 3000000 AND
CountryLanguage.Percentage > 50; CountryLanguage.Percentage > 50 AND
LENGTH(Language) < LENGTH(City.Name) - 2;
set join_cache_level=2; set join_cache_level=2;
show variables like 'join_cache_level'; show variables like 'join_cache_level';
@@ -185,14 +197,16 @@ SELECT City.Name, Country.Name, CountryLanguage.Language
WHERE City.Country=Country.Code AND WHERE City.Country=Country.Code AND
CountryLanguage.Country=Country.Code AND CountryLanguage.Country=Country.Code AND
City.Name LIKE 'L%' AND Country.Population > 3000000 AND City.Name LIKE 'L%' AND Country.Population > 3000000 AND
CountryLanguage.Percentage > 50; CountryLanguage.Percentage > 50 AND
LENGTH(Language) < LENGTH(City.Name) - 2;
SELECT City.Name, Country.Name, CountryLanguage.Language SELECT City.Name, Country.Name, CountryLanguage.Language
FROM City,Country,CountryLanguage FROM City,Country,CountryLanguage
WHERE City.Country=Country.Code AND WHERE City.Country=Country.Code AND
CountryLanguage.Country=Country.Code AND CountryLanguage.Country=Country.Code AND
City.Name LIKE 'L%' AND Country.Population > 3000000 AND City.Name LIKE 'L%' AND Country.Population > 3000000 AND
CountryLanguage.Percentage > 50; CountryLanguage.Percentage > 50 AND
LENGTH(Language) < LENGTH(City.Name) - 2;
set join_cache_level=3; set join_cache_level=3;
show variables like 'join_cache_level'; show variables like 'join_cache_level';
@@ -212,14 +226,16 @@ SELECT City.Name, Country.Name, CountryLanguage.Language
WHERE City.Country=Country.Code AND WHERE City.Country=Country.Code AND
CountryLanguage.Country=Country.Code AND CountryLanguage.Country=Country.Code AND
City.Name LIKE 'L%' AND Country.Population > 3000000 AND City.Name LIKE 'L%' AND Country.Population > 3000000 AND
CountryLanguage.Percentage > 50; CountryLanguage.Percentage > 50 AND
LENGTH(Language) < LENGTH(City.Name) - 2;
SELECT City.Name, Country.Name, CountryLanguage.Language SELECT City.Name, Country.Name, CountryLanguage.Language
FROM City,Country,CountryLanguage FROM City,Country,CountryLanguage
WHERE City.Country=Country.Code AND WHERE City.Country=Country.Code AND
CountryLanguage.Country=Country.Code AND CountryLanguage.Country=Country.Code AND
City.Name LIKE 'L%' AND Country.Population > 3000000 AND City.Name LIKE 'L%' AND Country.Population > 3000000 AND
CountryLanguage.Percentage > 50; CountryLanguage.Percentage > 50 AND
LENGTH(Language) < LENGTH(City.Name) - 2;
set join_cache_level=4; set join_cache_level=4;
show variables like 'join_cache_level'; show variables like 'join_cache_level';
@@ -239,14 +255,16 @@ SELECT City.Name, Country.Name, CountryLanguage.Language
WHERE City.Country=Country.Code AND WHERE City.Country=Country.Code AND
CountryLanguage.Country=Country.Code AND CountryLanguage.Country=Country.Code AND
City.Name LIKE 'L%' AND Country.Population > 3000000 AND City.Name LIKE 'L%' AND Country.Population > 3000000 AND
CountryLanguage.Percentage > 50; CountryLanguage.Percentage > 50 AND
LENGTH(Language) < LENGTH(City.Name) - 2;
SELECT City.Name, Country.Name, CountryLanguage.Language SELECT City.Name, Country.Name, CountryLanguage.Language
FROM City,Country,CountryLanguage FROM City,Country,CountryLanguage
WHERE City.Country=Country.Code AND WHERE City.Country=Country.Code AND
CountryLanguage.Country=Country.Code AND CountryLanguage.Country=Country.Code AND
City.Name LIKE 'L%' AND Country.Population > 3000000 AND City.Name LIKE 'L%' AND Country.Population > 3000000 AND
CountryLanguage.Percentage > 50; CountryLanguage.Percentage > 50 AND
LENGTH(Language) < LENGTH(City.Name) - 2;
set join_cache_level=default; set join_cache_level=default;
set join_buffer_size=default; set join_buffer_size=default;
@@ -290,14 +308,16 @@ SELECT City.Name, Country.Name, CountryLanguage.Language
WHERE City.Country=Country.Code AND WHERE City.Country=Country.Code AND
CountryLanguage.Country=Country.Code AND CountryLanguage.Country=Country.Code AND
City.Name LIKE 'L%' AND Country.Population > 3000000 AND City.Name LIKE 'L%' AND Country.Population > 3000000 AND
CountryLanguage.Percentage > 50; CountryLanguage.Percentage > 50 AND
LENGTH(Language) < LENGTH(City.Name) - 2;
SELECT City.Name, Country.Name, CountryLanguage.Language SELECT City.Name, Country.Name, CountryLanguage.Language
FROM City,Country,CountryLanguage FROM City,Country,CountryLanguage
WHERE City.Country=Country.Code AND WHERE City.Country=Country.Code AND
CountryLanguage.Country=Country.Code AND CountryLanguage.Country=Country.Code AND
City.Name LIKE 'L%' AND Country.Population > 3000000 AND City.Name LIKE 'L%' AND Country.Population > 3000000 AND
CountryLanguage.Percentage > 50; CountryLanguage.Percentage > 50 AND
LENGTH(Language) < LENGTH(City.Name) - 2;
EXPLAIN EXPLAIN
SELECT Name FROM City SELECT Name FROM City
@@ -340,14 +360,16 @@ SELECT City.Name, Country.Name, CountryLanguage.Language
WHERE City.Country=Country.Code AND WHERE City.Country=Country.Code AND
CountryLanguage.Country=Country.Code AND CountryLanguage.Country=Country.Code AND
City.Name LIKE 'L%' AND Country.Population > 3000000 AND City.Name LIKE 'L%' AND Country.Population > 3000000 AND
CountryLanguage.Percentage > 50; CountryLanguage.Percentage > 50 AND
LENGTH(Language) < LENGTH(City.Name) - 2;
SELECT City.Name, Country.Name, CountryLanguage.Language SELECT City.Name, Country.Name, CountryLanguage.Language
FROM City,Country,CountryLanguage FROM City,Country,CountryLanguage
WHERE City.Country=Country.Code AND WHERE City.Country=Country.Code AND
CountryLanguage.Country=Country.Code AND CountryLanguage.Country=Country.Code AND
City.Name LIKE 'L%' AND Country.Population > 3000000 AND City.Name LIKE 'L%' AND Country.Population > 3000000 AND
CountryLanguage.Percentage > 50; CountryLanguage.Percentage > 50 AND
LENGTH(Language) < LENGTH(City.Name) - 2;
EXPLAIN EXPLAIN
SELECT Name FROM City SELECT Name FROM City
@@ -391,14 +413,16 @@ SELECT City.Name, Country.Name, CountryLanguage.Language
WHERE City.Country=Country.Code AND WHERE City.Country=Country.Code AND
CountryLanguage.Country=Country.Code AND CountryLanguage.Country=Country.Code AND
City.Name LIKE 'L%' AND Country.Population > 3000000 AND City.Name LIKE 'L%' AND Country.Population > 3000000 AND
CountryLanguage.Percentage > 50; CountryLanguage.Percentage > 50 AND
LENGTH(Language) < LENGTH(City.Name) - 2;
SELECT City.Name, Country.Name, CountryLanguage.Language SELECT City.Name, Country.Name, CountryLanguage.Language
FROM City,Country,CountryLanguage FROM City,Country,CountryLanguage
WHERE City.Country=Country.Code AND WHERE City.Country=Country.Code AND
CountryLanguage.Country=Country.Code AND CountryLanguage.Country=Country.Code AND
City.Name LIKE 'L%' AND Country.Population > 3000000 AND City.Name LIKE 'L%' AND Country.Population > 3000000 AND
CountryLanguage.Percentage > 50; CountryLanguage.Percentage > 50 AND
LENGTH(Language) < LENGTH(City.Name) - 2;
EXPLAIN EXPLAIN
SELECT Name FROM City SELECT Name FROM City
@@ -440,14 +464,16 @@ SELECT City.Name, Country.Name, CountryLanguage.Language
WHERE City.Country=Country.Code AND WHERE City.Country=Country.Code AND
CountryLanguage.Country=Country.Code AND CountryLanguage.Country=Country.Code AND
City.Name LIKE 'L%' AND Country.Population > 3000000 AND City.Name LIKE 'L%' AND Country.Population > 3000000 AND
CountryLanguage.Percentage > 50; CountryLanguage.Percentage > 50 AND
LENGTH(Language) < LENGTH(City.Name) - 2;
SELECT City.Name, Country.Name, CountryLanguage.Language SELECT City.Name, Country.Name, CountryLanguage.Language
FROM City,Country,CountryLanguage FROM City,Country,CountryLanguage
WHERE City.Country=Country.Code AND WHERE City.Country=Country.Code AND
CountryLanguage.Country=Country.Code AND CountryLanguage.Country=Country.Code AND
City.Name LIKE 'L%' AND Country.Population > 3000000 AND City.Name LIKE 'L%' AND Country.Population > 3000000 AND
CountryLanguage.Percentage > 50; CountryLanguage.Percentage > 50 AND
LENGTH(Language) < LENGTH(City.Name) - 2;
EXPLAIN EXPLAIN
SELECT Name FROM City SELECT Name FROM City
@@ -489,14 +515,16 @@ SELECT City.Name, Country.Name, CountryLanguage.Language
WHERE City.Country=Country.Code AND WHERE City.Country=Country.Code AND
CountryLanguage.Country=Country.Code AND CountryLanguage.Country=Country.Code AND
City.Name LIKE 'L%' AND Country.Population > 3000000 AND City.Name LIKE 'L%' AND Country.Population > 3000000 AND
CountryLanguage.Percentage > 50; CountryLanguage.Percentage > 50 AND
LENGTH(Language) < LENGTH(City.Name) - 2;
SELECT City.Name, Country.Name, CountryLanguage.Language SELECT City.Name, Country.Name, CountryLanguage.Language
FROM City,Country,CountryLanguage FROM City,Country,CountryLanguage
WHERE City.Country=Country.Code AND WHERE City.Country=Country.Code AND
CountryLanguage.Country=Country.Code AND CountryLanguage.Country=Country.Code AND
City.Name LIKE 'L%' AND Country.Population > 3000000 AND City.Name LIKE 'L%' AND Country.Population > 3000000 AND
CountryLanguage.Percentage > 50; CountryLanguage.Percentage > 50 AND
LENGTH(Language) < LENGTH(City.Name) - 2;
EXPLAIN EXPLAIN
SELECT Name FROM City SELECT Name FROM City
@@ -538,14 +566,16 @@ SELECT City.Name, Country.Name, CountryLanguage.Language
WHERE City.Country=Country.Code AND WHERE City.Country=Country.Code AND
CountryLanguage.Country=Country.Code AND CountryLanguage.Country=Country.Code AND
City.Name LIKE 'L%' AND Country.Population > 3000000 AND City.Name LIKE 'L%' AND Country.Population > 3000000 AND
CountryLanguage.Percentage > 50; CountryLanguage.Percentage > 50 AND
LENGTH(Language) < LENGTH(City.Name) - 2;
SELECT City.Name, Country.Name, CountryLanguage.Language SELECT City.Name, Country.Name, CountryLanguage.Language
FROM City,Country,CountryLanguage FROM City,Country,CountryLanguage
WHERE City.Country=Country.Code AND WHERE City.Country=Country.Code AND
CountryLanguage.Country=Country.Code AND CountryLanguage.Country=Country.Code AND
City.Name LIKE 'L%' AND Country.Population > 3000000 AND City.Name LIKE 'L%' AND Country.Population > 3000000 AND
CountryLanguage.Percentage > 50; CountryLanguage.Percentage > 50 AND
LENGTH(Language) < LENGTH(City.Name) - 2;
EXPLAIN EXPLAIN
SELECT Name FROM City SELECT Name FROM City
@@ -590,14 +620,16 @@ SELECT City.Name, Country.Name, CountryLanguage.Language
WHERE City.Country=Country.Code AND WHERE City.Country=Country.Code AND
CountryLanguage.Country=Country.Code AND CountryLanguage.Country=Country.Code AND
City.Name LIKE 'L%' AND Country.Population > 3000000 AND City.Name LIKE 'L%' AND Country.Population > 3000000 AND
CountryLanguage.Percentage > 50; CountryLanguage.Percentage > 50 AND
LENGTH(Language) < LENGTH(City.Name) - 2;
SELECT City.Name, Country.Name, CountryLanguage.Language SELECT City.Name, Country.Name, CountryLanguage.Language
FROM City,Country,CountryLanguage FROM City,Country,CountryLanguage
WHERE City.Country=Country.Code AND WHERE City.Country=Country.Code AND
CountryLanguage.Country=Country.Code AND CountryLanguage.Country=Country.Code AND
City.Name LIKE 'L%' AND Country.Population > 3000000 AND City.Name LIKE 'L%' AND Country.Population > 3000000 AND
CountryLanguage.Percentage > 50; CountryLanguage.Percentage > 50 AND
LENGTH(Language) < LENGTH(City.Name) - 2;
EXPLAIN EXPLAIN
SELECT Name FROM City SELECT Name FROM City
@@ -626,14 +658,16 @@ SELECT City.Name, Country.Name, CountryLanguage.Language
WHERE City.Country=Country.Code AND WHERE City.Country=Country.Code AND
CountryLanguage.Country=Country.Code AND CountryLanguage.Country=Country.Code AND
City.Name LIKE 'L%' AND Country.Population > 3000000 AND City.Name LIKE 'L%' AND Country.Population > 3000000 AND
CountryLanguage.Percentage > 50; CountryLanguage.Percentage > 50 AND
LENGTH(Language) < LENGTH(City.Name) - 2;
SELECT City.Name, Country.Name, CountryLanguage.Language SELECT City.Name, Country.Name, CountryLanguage.Language
FROM City,Country,CountryLanguage FROM City,Country,CountryLanguage
WHERE City.Country=Country.Code AND WHERE City.Country=Country.Code AND
CountryLanguage.Country=Country.Code AND CountryLanguage.Country=Country.Code AND
City.Name LIKE 'L%' AND Country.Population > 3000000 AND City.Name LIKE 'L%' AND Country.Population > 3000000 AND
CountryLanguage.Percentage > 50; CountryLanguage.Percentage > 50 AND
LENGTH(Language) < LENGTH(City.Name) - 2;
EXPLAIN EXPLAIN
SELECT Name FROM City SELECT Name FROM City
@@ -662,14 +696,16 @@ SELECT City.Name, Country.Name, CountryLanguage.Language
WHERE City.Country=Country.Code AND WHERE City.Country=Country.Code AND
CountryLanguage.Country=Country.Code AND CountryLanguage.Country=Country.Code AND
City.Name LIKE 'L%' AND Country.Population > 3000000 AND City.Name LIKE 'L%' AND Country.Population > 3000000 AND
CountryLanguage.Percentage > 50; CountryLanguage.Percentage > 50 AND
LENGTH(Language) < LENGTH(City.Name) - 2;
SELECT City.Name, Country.Name, CountryLanguage.Language SELECT City.Name, Country.Name, CountryLanguage.Language
FROM City,Country,CountryLanguage FROM City,Country,CountryLanguage
WHERE City.Country=Country.Code AND WHERE City.Country=Country.Code AND
CountryLanguage.Country=Country.Code AND CountryLanguage.Country=Country.Code AND
City.Name LIKE 'L%' AND Country.Population > 3000000 AND City.Name LIKE 'L%' AND Country.Population > 3000000 AND
CountryLanguage.Percentage > 50; CountryLanguage.Percentage > 50 AND
LENGTH(Language) < LENGTH(City.Name) - 2;
EXPLAIN EXPLAIN
SELECT Name FROM City SELECT Name FROM City
@@ -698,14 +734,16 @@ SELECT City.Name, Country.Name, CountryLanguage.Language
WHERE City.Country=Country.Code AND WHERE City.Country=Country.Code AND
CountryLanguage.Country=Country.Code AND CountryLanguage.Country=Country.Code AND
City.Name LIKE 'L%' AND Country.Population > 3000000 AND City.Name LIKE 'L%' AND Country.Population > 3000000 AND
CountryLanguage.Percentage > 50; CountryLanguage.Percentage > 50 AND
LENGTH(Language) < LENGTH(City.Name) - 2;
SELECT City.Name, Country.Name, CountryLanguage.Language SELECT City.Name, Country.Name, CountryLanguage.Language
FROM City,Country,CountryLanguage FROM City,Country,CountryLanguage
WHERE City.Country=Country.Code AND WHERE City.Country=Country.Code AND
CountryLanguage.Country=Country.Code AND CountryLanguage.Country=Country.Code AND
City.Name LIKE 'L%' AND Country.Population > 3000000 AND City.Name LIKE 'L%' AND Country.Population > 3000000 AND
CountryLanguage.Percentage > 50; CountryLanguage.Percentage > 50 AND
LENGTH(Language) < LENGTH(City.Name) - 2;
EXPLAIN EXPLAIN
SELECT Name FROM City SELECT Name FROM City
@@ -734,14 +772,16 @@ SELECT City.Name, Country.Name, CountryLanguage.Language
WHERE City.Country=Country.Code AND WHERE City.Country=Country.Code AND
CountryLanguage.Country=Country.Code AND CountryLanguage.Country=Country.Code AND
City.Name LIKE 'L%' AND Country.Population > 3000000 AND City.Name LIKE 'L%' AND Country.Population > 3000000 AND
CountryLanguage.Percentage > 50; CountryLanguage.Percentage > 50 AND
LENGTH(Language) < LENGTH(City.Name) - 2;
SELECT City.Name, Country.Name, CountryLanguage.Language SELECT City.Name, Country.Name, CountryLanguage.Language
FROM City,Country,CountryLanguage FROM City,Country,CountryLanguage
WHERE City.Country=Country.Code AND WHERE City.Country=Country.Code AND
CountryLanguage.Country=Country.Code AND CountryLanguage.Country=Country.Code AND
City.Name LIKE 'L%' AND Country.Population > 3000000 AND City.Name LIKE 'L%' AND Country.Population > 3000000 AND
CountryLanguage.Percentage > 50; CountryLanguage.Percentage > 50 AND
LENGTH(Language) < LENGTH(City.Name) - 2;
EXPLAIN EXPLAIN
SELECT Name FROM City SELECT Name FROM City
@@ -770,14 +810,16 @@ SELECT City.Name, Country.Name, CountryLanguage.Language
WHERE City.Country=Country.Code AND WHERE City.Country=Country.Code AND
CountryLanguage.Country=Country.Code AND CountryLanguage.Country=Country.Code AND
City.Name LIKE 'L%' AND Country.Population > 3000000 AND City.Name LIKE 'L%' AND Country.Population > 3000000 AND
CountryLanguage.Percentage > 50; CountryLanguage.Percentage > 50 AND
LENGTH(Language) < LENGTH(City.Name) - 2;
SELECT City.Name, Country.Name, CountryLanguage.Language SELECT City.Name, Country.Name, CountryLanguage.Language
FROM City,Country,CountryLanguage FROM City,Country,CountryLanguage
WHERE City.Country=Country.Code AND WHERE City.Country=Country.Code AND
CountryLanguage.Country=Country.Code AND CountryLanguage.Country=Country.Code AND
City.Name LIKE 'L%' AND Country.Population > 3000000 AND City.Name LIKE 'L%' AND Country.Population > 3000000 AND
CountryLanguage.Percentage > 50; CountryLanguage.Percentage > 50 AND
LENGTH(Language) < LENGTH(City.Name) - 2;
EXPLAIN EXPLAIN
SELECT Name FROM City SELECT Name FROM City

15
sql/sql_select.cc
View File

@@ -6445,6 +6445,7 @@ static bool create_hj_key_for_table(JOIN *join, JOIN_TAB *join_tab,
} while (keyuse->table == table && keyuse->is_for_hash_join()); } while (keyuse->table == table && keyuse->is_for_hash_join());
if (!key_parts) if (!key_parts)
DBUG_RETURN(TRUE); DBUG_RETURN(TRUE);
/* This memory is allocated only once for the joined table join_tab */
if (!(keyinfo= (KEY *) thd->alloc(sizeof(KEY))) || if (!(keyinfo= (KEY *) thd->alloc(sizeof(KEY))) ||
!(key_part_info = (KEY_PART_INFO *) thd->alloc(sizeof(KEY_PART_INFO)* !(key_part_info = (KEY_PART_INFO *) thd->alloc(sizeof(KEY_PART_INFO)*
key_parts))) key_parts)))
@@ -6525,18 +6526,14 @@ static bool create_ref_for_key(JOIN *join, JOIN_TAB *j,
{ {
if (!(~used_tables & keyuse->used_tables)) if (!(~used_tables & keyuse->used_tables))
{ {
if (is_hash_join_key_no(key) && if ((is_hash_join_key_no(key) &&
(keyparts == 0 || keyuse->keypart != (keyuse-1)->keypart)) (keyparts == 0 || keyuse->keypart != (keyuse-1)->keypart)) ||
(!is_hash_join_key_no(key) && keyparts == keyuse->keypart &&
!(found_part_ref_or_null & keyuse->optimize)))
{ {
length+= keyinfo->key_part[keyparts].store_length; length+= keyinfo->key_part[keyparts].store_length;
keyparts++; keyparts++;
} found_part_ref_or_null|= keyuse->optimize & ~KEY_OPTIMIZE_EQ;
else if (!is_hash_join_key_no(key) && keyparts == keyuse->keypart &&
!(found_part_ref_or_null & keyuse->optimize))
{
length+= keyinfo->key_part[keyuse->keypart].store_length;
found_part_ref_or_null|= keyuse->optimize;
keyparts++;
} }
} }
keyuse++; keyuse++;