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642aa4366d
tell the optimizer that every TokuDB "clustering" index is the "covering" index in the MariaDB optimizer sense.
23 lines
1.1 KiB
Text
23 lines
1.1 KiB
Text
SET DEFAULT_STORAGE_ENGINE = 'tokudb';
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DROP TABLE IF EXISTS foo;
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set session tokudb_prelock_empty=0;
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create table foo (a int, b int, c int, primary key (a), key (b) clustering=yes);
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insert into foo values (1,1,1),(2,2,2),(3,3,3),(4,4,4),(5,5,5);
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# Both explains should use primary key;
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explain select * from foo;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE foo index NULL b 5 NULL 5 Using index
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explain select a from foo;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE foo index NULL PRIMARY 4 NULL 5 Using index
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DROP table foo;
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create table foo (a int, b int, c int, key (b) clustering=yes, primary key (a));
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insert into foo values (1,1,1),(2,2,2),(3,3,3),(4,4,4),(5,5,5);
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# Both explains should use primary key;
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explain select * from foo;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE foo index NULL b 5 NULL 5 Using index
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explain select a from foo;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE foo index NULL PRIMARY 4 NULL 5 Using index
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DROP TABLE foo;
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