[Maria-developers] Please review: MWL#121: DS-MRR support for clustered primary keys
Hello Igor, Please find below the combined patch for MWL#121. It is ready for review. diff -urN --exclude='.*' maria-5.3-dsmrr-for-cpk-clean/mysql-test/r/innodb_mrr_cpk.result maria-5.3-dsmrr-for-cpk-noc/mysql-test/r/innodb_mrr_cpk.result --- maria-5.3-dsmrr-for-cpk-clean/mysql-test/r/innodb_mrr_cpk.result 1970-01-01 03:00:00.000000000 +0300 +++ maria-5.3-dsmrr-for-cpk-noc/mysql-test/r/innodb_mrr_cpk.result 2010-06-22 23:28:02.000000000 +0400 @@ -0,0 +1,148 @@ +drop table if exists t0,t1,t2,t3; +set @save_join_cache_level=@@join_cache_level; +set join_cache_level=6; +set @save_storage_engine=@@storage_engine; +set storage_engine=innodb; +create table t0(a int); +insert into t0 values (0),(1),(2),(3),(4),(5),(6),(7),(8),(9); +create table t1(a char(8), b char(8), filler char(100), primary key(a)); +show create table t1; +Table Create Table +t1 CREATE TABLE `t1` ( + `a` char(8) NOT NULL DEFAULT '', + `b` char(8) DEFAULT NULL, + `filler` char(100) DEFAULT NULL, + PRIMARY KEY (`a`) +) ENGINE=InnoDB DEFAULT CHARSET=latin1 +insert into t1 select +concat('a-', 1000 + A.a + B.a*10 + C.a*100, '=A'), +concat('b-', 1000 + A.a + B.a*10 + C.a*100, '=B'), +'filler' +from t0 A, t0 B, t0 C; +create table t2 (a char(8)); +insert into t2 values ('a-1010=A'), ('a-1030=A'), ('a-1020=A'); +This should use join buffer: +explain select * from t1, t2 where t1.a=t2.a; +id select_type table type possible_keys key key_len ref rows Extra +1 SIMPLE t2 ALL NULL NULL NULL NULL 3 +1 SIMPLE t1 eq_ref PRIMARY PRIMARY 8 test.t2.a 1 Using join buffer +This output must be sorted by value of t1.a: +select * from t1, t2 where t1.a=t2.a; +a b filler a +a-1010=A b-1010=B filler a-1010=A +a-1020=A b-1020=B filler a-1020=A +a-1030=A b-1030=B filler a-1030=A +drop table t1, t2; +create table t1( +a char(8) character set utf8, b int, filler char(100), +primary key(a,b) +); +insert into t1 select +concat('a-', 1000 + A.a + B.a*10 + C.a*100, '=A'), +1000 + A.a + B.a*10 + C.a*100, +'filler' +from t0 A, t0 B, t0 C; +create table t2 (a char(8) character set utf8, b int); +insert into t2 values ('a-1010=A', 1010), ('a-1030=A', 1030), ('a-1020=A', 1020); +explain select * from t1, t2 where t1.a=t2.a and t1.b=t2.b; +id select_type table type possible_keys key key_len ref rows Extra +1 SIMPLE t2 ALL NULL NULL NULL NULL 3 +1 SIMPLE t1 eq_ref PRIMARY PRIMARY 28 test.t2.a,test.t2.b 1 Using join buffer +select * from t1, t2 where t1.a=t2.a and t1.b=t2.b; +a b filler a b +a-1010=A 1010 filler a-1010=A 1010 +a-1020=A 1020 filler a-1020=A 1020 +a-1030=A 1030 filler a-1030=A 1030 +insert into t2 values ('a-1030=A', 1030), ('a-1020=A', 1020); +explain select * from t1, t2 where t1.a=t2.a and t1.b=t2.b; +id select_type table type possible_keys key key_len ref rows Extra +1 SIMPLE t2 ALL NULL NULL NULL NULL 5 +1 SIMPLE t1 eq_ref PRIMARY PRIMARY 28 test.t2.a,test.t2.b 1 Using join buffer +select * from t1, t2 where t1.a=t2.a and t1.b=t2.b; +a b filler a b +a-1010=A 1010 filler a-1010=A 1010 +a-1020=A 1020 filler a-1020=A 1020 +a-1020=A 1020 filler a-1020=A 1020 +a-1030=A 1030 filler a-1030=A 1030 +a-1030=A 1030 filler a-1030=A 1030 +drop table t1, t2; +create table t1( +a varchar(8) character set utf8, b int, filler char(100), +primary key(a,b) +); +insert into t1 select +concat('a-', 1000 + A.a + B.a*10 + C.a*100, '=A'), +1000 + A.a + B.a*10 + C.a*100, +'filler' +from t0 A, t0 B, t0 C; +create table t2 (a char(8) character set utf8, b int); +insert into t2 values ('a-1010=A', 1010), ('a-1030=A', 1030), ('a-1020=A', 1020); +explain select * from t1, t2 where t1.a=t2.a and t1.b=t2.b; +id select_type table type possible_keys key key_len ref rows Extra +1 SIMPLE t2 ALL NULL NULL NULL NULL 3 +1 SIMPLE t1 eq_ref PRIMARY PRIMARY 30 test.t2.a,test.t2.b 1 Using index condition(BKA); Using join buffer +select * from t1, t2 where t1.a=t2.a and t1.b=t2.b; +a b filler a b +a-1010=A 1010 filler a-1010=A 1010 +a-1020=A 1020 filler a-1020=A 1020 +a-1030=A 1030 filler a-1030=A 1030 +explain select * from t1, t2 where t1.a=t2.a; +id select_type table type possible_keys key key_len ref rows Extra +1 SIMPLE t2 ALL NULL NULL NULL NULL 3 +1 SIMPLE t1 ref PRIMARY PRIMARY 26 test.t2.a 1 Using index condition(BKA); Using join buffer +select * from t1, t2 where t1.a=t2.a; +a b filler a b +a-1010=A 1010 filler a-1010=A 1010 +a-1020=A 1020 filler a-1020=A 1020 +a-1030=A 1030 filler a-1030=A 1030 +drop table t1, t2; +create table t1 (a int, b int, c int, filler char(100), primary key(a,b,c)); +insert into t1 select A.a, B.a, C.a, 'filler' from t0 A, t0 B, t0 C; +insert into t1 values (11, 11, 11, 'filler'); +insert into t1 values (11, 11, 12, 'filler'); +insert into t1 values (11, 11, 13, 'filler'); +insert into t1 values (11, 22, 1234, 'filler'); +insert into t1 values (11, 33, 124, 'filler'); +insert into t1 values (11, 33, 125, 'filler'); +create table t2 (a int, b int); +insert into t2 values (11,33), (11,22), (11,11); +explain select * from t1, t2 where t1.a=t2.a and t1.b=t2.b; +id select_type table type possible_keys key key_len ref rows Extra +1 SIMPLE t2 ALL NULL NULL NULL NULL 3 +1 SIMPLE t1 ref PRIMARY PRIMARY 8 test.t2.a,test.t2.b 1 Using join buffer +select * from t1, t2 where t1.a=t2.a and t1.b=t2.b; +a b c filler a b +11 11 11 filler 11 11 +11 11 12 filler 11 11 +11 11 13 filler 11 11 +11 22 1234 filler 11 22 +11 33 124 filler 11 33 +11 33 125 filler 11 33 +set join_cache_level=0; +select * from t1, t2 where t1.a=t2.a and t1.b=t2.b; +a b c filler a b +11 33 124 filler 11 33 +11 33 125 filler 11 33 +11 22 1234 filler 11 22 +11 11 11 filler 11 11 +11 11 12 filler 11 11 +11 11 13 filler 11 11 +set join_cache_level=6; +explain select * from t1, t2 where t1.a=t2.a and t2.b + t1.b > 100; +id select_type table type possible_keys key key_len ref rows Extra +1 SIMPLE t2 ALL NULL NULL NULL NULL 3 +1 SIMPLE t1 ref PRIMARY PRIMARY 4 test.t2.a 1 Using index condition(BKA); Using join buffer +select * from t1, t2 where t1.a=t2.a and t2.b + t1.b > 100; +a b c filler a b +set optimizer_switch='index_condition_pushdown=off'; +explain select * from t1, t2 where t1.a=t2.a and t2.b + t1.b > 100; +id select_type table type possible_keys key key_len ref rows Extra +1 SIMPLE t2 ALL NULL NULL NULL NULL 3 +1 SIMPLE t1 ref PRIMARY PRIMARY 4 test.t2.a 1 Using where; Using join buffer +select * from t1, t2 where t1.a=t2.a and t2.b + t1.b > 100; +a b c filler a b +set optimizer_switch='index_condition_pushdown=on'; +drop table t1,t2; +set @@join_cache_level= @save_join_cache_level; +set storage_engine=@save_storage_engine; +drop table t0; diff -urN --exclude='.*' maria-5.3-dsmrr-for-cpk-clean/mysql-test/r/innodb_mrr_cpk.result.moved maria-5.3-dsmrr-for-cpk-noc/mysql-test/r/innodb_mrr_cpk.result.moved --- maria-5.3-dsmrr-for-cpk-clean/mysql-test/r/innodb_mrr_cpk.result.moved 1970-01-01 03:00:00.000000000 +0300 +++ maria-5.3-dsmrr-for-cpk-noc/mysql-test/r/innodb_mrr_cpk.result.moved 2010-06-22 19:23:18.000000000 +0400 @@ -0,0 +1,122 @@ +drop table if exists t0,t1,t2,t3; +set @save_join_cache_level=@@join_cache_level; +set join_cache_level=6; +set @save_storage_engine=@@storage_engine; +set storage_engine=innodb; +create table t0(a int); +insert into t0 values (0),(1),(2),(3),(4),(5),(6),(7),(8),(9); +create table t1(a char(8), b char(8), filler char(100), primary key(a)); +show create table t1; +Table Create Table +t1 CREATE TABLE `t1` ( + `a` char(8) NOT NULL DEFAULT '', + `b` char(8) DEFAULT NULL, + `filler` char(100) DEFAULT NULL, + PRIMARY KEY (`a`) +) ENGINE=InnoDB DEFAULT CHARSET=latin1 +insert into t1 select +concat('a-', 1000 + A.a + B.a*10 + C.a*100, '=A'), +concat('b-', 1000 + A.a + B.a*10 + C.a*100, '=B'), +'filler' +from t0 A, t0 B, t0 C; +create table t2 (a char(8)); +insert into t2 values ('a-1010=A'), ('a-1030=A'), ('a-1020=A'); +This should use join buffer: +explain select * from t1, t2 where t1.a=t2.a; +id select_type table type possible_keys key key_len ref rows Extra +1 SIMPLE t2 ALL NULL NULL NULL NULL 3 +1 SIMPLE t1 eq_ref PRIMARY PRIMARY 8 test.t2.a 1 Using join buffer +This output must be sorted by value of t1.a: +select * from t1, t2 where t1.a=t2.a; +a b filler a +a-1010=A b-1010=B filler a-1010=A +a-1020=A b-1020=B filler a-1020=A +a-1030=A b-1030=B filler a-1030=A +drop table t1, t2; +create table t1( +a char(8) character set utf8, b int, filler char(100), +primary key(a,b) +); +insert into t1 select +concat('a-', 1000 + A.a + B.a*10 + C.a*100, '=A'), +1000 + A.a + B.a*10 + C.a*100, +'filler' +from t0 A, t0 B, t0 C; +create table t2 (a char(8) character set utf8, b int); +insert into t2 values ('a-1010=A', 1010), ('a-1030=A', 1030), ('a-1020=A', 1020); +explain select * from t1, t2 where t1.a=t2.a and t1.b=t2.b; +id select_type table type possible_keys key key_len ref rows Extra +1 SIMPLE t2 ALL NULL NULL NULL NULL 3 +1 SIMPLE t1 eq_ref PRIMARY PRIMARY 28 test.t2.a,test.t2.b 1 Using join buffer +select * from t1, t2 where t1.a=t2.a and t1.b=t2.b; +a b filler a b +a-1010=A 1010 filler a-1010=A 1010 +a-1020=A 1020 filler a-1020=A 1020 +a-1030=A 1030 filler a-1030=A 1030 +drop table t1, t2; +create table t1( +a varchar(8) character set utf8, b int, filler char(100), +primary key(a,b) +); +insert into t1 select +concat('a-', 1000 + A.a + B.a*10 + C.a*100, '=A'), +1000 + A.a + B.a*10 + C.a*100, +'filler' +from t0 A, t0 B, t0 C; +create table t2 (a char(8) character set utf8, b int); +insert into t2 values ('a-1010=A', 1010), ('a-1030=A', 1030), ('a-1020=A', 1020); +explain select * from t1, t2 where t1.a=t2.a and t1.b=t2.b; +id select_type table type possible_keys key key_len ref rows Extra +1 SIMPLE t2 ALL NULL NULL NULL NULL 3 +1 SIMPLE t1 eq_ref PRIMARY PRIMARY 30 test.t2.a,test.t2.b 1 Using index condition(BKA); Using join buffer +select * from t1, t2 where t1.a=t2.a and t1.b=t2.b; +a b filler a b +a-1010=A 1010 filler a-1010=A 1010 +a-1020=A 1020 filler a-1020=A 1020 +a-1030=A 1030 filler a-1030=A 1030 +explain select * from t1, t2 where t1.a=t2.a; +id select_type table type possible_keys key key_len ref rows Extra +1 SIMPLE t2 ALL NULL NULL NULL NULL 3 +1 SIMPLE t1 ref PRIMARY PRIMARY 26 test.t2.a 1 Using index condition(BKA); Using join buffer +select * from t1, t2 where t1.a=t2.a; +a b filler a b +a-1010=A 1010 filler a-1010=A 1010 +a-1020=A 1020 filler a-1020=A 1020 +a-1030=A 1030 filler a-1030=A 1030 +drop table t1, t2; +create table t1 (a int, b int, c int, filler char(100), primary key(a,b,c)); +insert into t1 select A.a, B.a, C.a, 'filler' from t0 A, t0 B, t0 C; +insert into t1 values (11, 11, 11, 'filler'); +insert into t1 values (11, 11, 12, 'filler'); +insert into t1 values (11, 11, 13, 'filler'); +insert into t1 values (11, 22, 1234, 'filler'); +insert into t1 values (11, 33, 124, 'filler'); +insert into t1 values (11, 33, 125, 'filler'); +create table t2 (a int, b int); +insert into t2 values (11,33), (11,22), (11,11); +explain select * from t1, t2 where t1.a=t2.a and t1.b=t2.b; +id select_type table type possible_keys key key_len ref rows Extra +1 SIMPLE t2 ALL NULL NULL NULL NULL 3 +1 SIMPLE t1 ref PRIMARY PRIMARY 8 test.t2.a,test.t2.b 1 Using join buffer +select * from t1, t2 where t1.a=t2.a and t1.b=t2.b; +a b c filler a b +11 11 11 filler 11 11 +11 11 12 filler 11 11 +11 11 13 filler 11 11 +11 22 1234 filler 11 22 +11 33 124 filler 11 33 +11 33 125 filler 11 33 +set join_cache_level=0; +select * from t1, t2 where t1.a=t2.a and t1.b=t2.b; +a b c filler a b +11 33 124 filler 11 33 +11 33 125 filler 11 33 +11 22 1234 filler 11 22 +11 11 11 filler 11 11 +11 11 12 filler 11 11 +11 11 13 filler 11 11 +set join_cache_level=6; +drop table t1,t2; +set @@join_cache_level= @save_join_cache_level; +set storage_engine=@save_storage_engine; +drop table t0; diff -urN --exclude='.*' maria-5.3-dsmrr-for-cpk-clean/mysql-test/t/innodb_mrr_cpk.test maria-5.3-dsmrr-for-cpk-noc/mysql-test/t/innodb_mrr_cpk.test --- maria-5.3-dsmrr-for-cpk-clean/mysql-test/t/innodb_mrr_cpk.test 1970-01-01 03:00:00.000000000 +0300 +++ maria-5.3-dsmrr-for-cpk-noc/mysql-test/t/innodb_mrr_cpk.test 2010-06-22 23:28:02.000000000 +0400 @@ -0,0 +1,137 @@ +# +# Tests for DS-MRR over clustered primary key. The only engine that supports +# this is InnoDB/XtraDB. +# +# Basic idea about testing +# - DS-MRR/CPK works only with BKA +# - Should also test index condition pushdown +# - Should also test whatever uses RANGE_SEQ_IF::skip_record() for filtering +# - Also test access using prefix of primary key +# +# - Forget about cost model, BKA's multi_range_read_info() call passes 10 for +# #rows, the call is there at all only for applicability check +# +-- source include/have_innodb.inc + +--disable_warnings +drop table if exists t0,t1,t2,t3; +--enable_warnings + +set @save_join_cache_level=@@join_cache_level; +set join_cache_level=6; + +set @save_storage_engine=@@storage_engine; +set storage_engine=innodb; + +create table t0(a int); +insert into t0 values (0),(1),(2),(3),(4),(5),(6),(7),(8),(9); +create table t1(a char(8), b char(8), filler char(100), primary key(a)); +show create table t1; + +insert into t1 select + concat('a-', 1000 + A.a + B.a*10 + C.a*100, '=A'), + concat('b-', 1000 + A.a + B.a*10 + C.a*100, '=B'), + 'filler' +from t0 A, t0 B, t0 C; + +create table t2 (a char(8)); +insert into t2 values ('a-1010=A'), ('a-1030=A'), ('a-1020=A'); + +--echo This should use join buffer: +explain select * from t1, t2 where t1.a=t2.a; + +--echo This output must be sorted by value of t1.a: +select * from t1, t2 where t1.a=t2.a; +drop table t1, t2; + +# Try multi-column indexes +create table t1( + a char(8) character set utf8, b int, filler char(100), + primary key(a,b) +); + +insert into t1 select + concat('a-', 1000 + A.a + B.a*10 + C.a*100, '=A'), + 1000 + A.a + B.a*10 + C.a*100, + 'filler' +from t0 A, t0 B, t0 C; + +create table t2 (a char(8) character set utf8, b int); +insert into t2 values ('a-1010=A', 1010), ('a-1030=A', 1030), ('a-1020=A', 1020); +explain select * from t1, t2 where t1.a=t2.a and t1.b=t2.b; +select * from t1, t2 where t1.a=t2.a and t1.b=t2.b; + +# Try with dataset that causes identical lookup keys: +insert into t2 values ('a-1030=A', 1030), ('a-1020=A', 1020); +explain select * from t1, t2 where t1.a=t2.a and t1.b=t2.b; +select * from t1, t2 where t1.a=t2.a and t1.b=t2.b; + +drop table t1, t2; + +create table t1( + a varchar(8) character set utf8, b int, filler char(100), + primary key(a,b) +); + +insert into t1 select + concat('a-', 1000 + A.a + B.a*10 + C.a*100, '=A'), + 1000 + A.a + B.a*10 + C.a*100, + 'filler' +from t0 A, t0 B, t0 C; + +create table t2 (a char(8) character set utf8, b int); +insert into t2 values ('a-1010=A', 1010), ('a-1030=A', 1030), ('a-1020=A', 1020); +explain select * from t1, t2 where t1.a=t2.a and t1.b=t2.b; +select * from t1, t2 where t1.a=t2.a and t1.b=t2.b; + +# +# Try scanning on a CPK prefix +# +explain select * from t1, t2 where t1.a=t2.a; +select * from t1, t2 where t1.a=t2.a; +drop table t1, t2; + +# +# The above example is not very interesting, as CPK prefix has +# only one match. Create a dataset where scan on CPK prefix +# would produce multiple matches: +# +create table t1 (a int, b int, c int, filler char(100), primary key(a,b,c)); +insert into t1 select A.a, B.a, C.a, 'filler' from t0 A, t0 B, t0 C; + +insert into t1 values (11, 11, 11, 'filler'); +insert into t1 values (11, 11, 12, 'filler'); +insert into t1 values (11, 11, 13, 'filler'); +insert into t1 values (11, 22, 1234, 'filler'); +insert into t1 values (11, 33, 124, 'filler'); +insert into t1 values (11, 33, 125, 'filler'); + +create table t2 (a int, b int); +insert into t2 values (11,33), (11,22), (11,11); + +explain select * from t1, t2 where t1.a=t2.a and t1.b=t2.b; +select * from t1, t2 where t1.a=t2.a and t1.b=t2.b; + +# Check a real resultset for comaprison: +set join_cache_level=0; +select * from t1, t2 where t1.a=t2.a and t1.b=t2.b; +set join_cache_level=6; + + +# +# Check that Index Condition Pushdown (BKA) actually works: +# +explain select * from t1, t2 where t1.a=t2.a and t2.b + t1.b > 100; +select * from t1, t2 where t1.a=t2.a and t2.b + t1.b > 100; + +set optimizer_switch='index_condition_pushdown=off'; +explain select * from t1, t2 where t1.a=t2.a and t2.b + t1.b > 100; +select * from t1, t2 where t1.a=t2.a and t2.b + t1.b > 100; +set optimizer_switch='index_condition_pushdown=on'; + +drop table t1,t2; + +set @@join_cache_level= @save_join_cache_level; +set storage_engine=@save_storage_engine; +drop table t0; + diff -urN --exclude='.*' maria-5.3-dsmrr-for-cpk-clean/mysql-test/t/innodb_mrr_cpk.test.moved maria-5.3-dsmrr-for-cpk-noc/mysql-test/t/innodb_mrr_cpk.test.moved --- maria-5.3-dsmrr-for-cpk-clean/mysql-test/t/innodb_mrr_cpk.test.moved 1970-01-01 03:00:00.000000000 +0300 +++ maria-5.3-dsmrr-for-cpk-noc/mysql-test/t/innodb_mrr_cpk.test.moved 2010-06-22 19:23:18.000000000 +0400 @@ -0,0 +1,128 @@ +# +# Tests for DS-MRR over clustered primary key. The only engine that supports +# this is InnoDB/XtraDB. +# +# Basic idea about testing +# - DS-MRR/CPK works only with BKA +# - Should also test index condition pushdown +# - Should also test whatever uses RANGE_SEQ_IF::skip_record() for filtering +# - Also test access using prefix of primary key +# +# - Forget about cost model, BKA's multi_range_read_info() call passes 10 for +# #rows, the call is there at all only for applicability check +# +-- source include/have_innodb.inc + +--disable_warnings +drop table if exists t0,t1,t2,t3; +--enable_warnings + +set @save_join_cache_level=@@join_cache_level; +set join_cache_level=6; + +set @save_storage_engine=@@storage_engine; +set storage_engine=innodb; + +create table t0(a int); +insert into t0 values (0),(1),(2),(3),(4),(5),(6),(7),(8),(9); +create table t1(a char(8), b char(8), filler char(100), primary key(a)); +show create table t1; + +insert into t1 select + concat('a-', 1000 + A.a + B.a*10 + C.a*100, '=A'), + concat('b-', 1000 + A.a + B.a*10 + C.a*100, '=B'), + 'filler' +from t0 A, t0 B, t0 C; + +create table t2 (a char(8)); +insert into t2 values ('a-1010=A'), ('a-1030=A'), ('a-1020=A'); + +--echo This should use join buffer: +explain select * from t1, t2 where t1.a=t2.a; + +--echo This output must be sorted by value of t1.a: +select * from t1, t2 where t1.a=t2.a; +drop table t1, t2; + +# Try multi-column indexes +create table t1( + a char(8) character set utf8, b int, filler char(100), + primary key(a,b) +); + +insert into t1 select + concat('a-', 1000 + A.a + B.a*10 + C.a*100, '=A'), + 1000 + A.a + B.a*10 + C.a*100, + 'filler' +from t0 A, t0 B, t0 C; + +create table t2 (a char(8) character set utf8, b int); +insert into t2 values ('a-1010=A', 1010), ('a-1030=A', 1030), ('a-1020=A', 1020); +explain select * from t1, t2 where t1.a=t2.a and t1.b=t2.b; +select * from t1, t2 where t1.a=t2.a and t1.b=t2.b; +drop table t1, t2; + +create table t1( + a varchar(8) character set utf8, b int, filler char(100), + primary key(a,b) +); + +insert into t1 select + concat('a-', 1000 + A.a + B.a*10 + C.a*100, '=A'), + 1000 + A.a + B.a*10 + C.a*100, + 'filler' +from t0 A, t0 B, t0 C; + +create table t2 (a char(8) character set utf8, b int); +insert into t2 values ('a-1010=A', 1010), ('a-1030=A', 1030), ('a-1020=A', 1020); +explain select * from t1, t2 where t1.a=t2.a and t1.b=t2.b; +select * from t1, t2 where t1.a=t2.a and t1.b=t2.b; + +# +# Try scanning on a CPK prefix +# +explain select * from t1, t2 where t1.a=t2.a; +select * from t1, t2 where t1.a=t2.a; +drop table t1, t2; + +# +# The above example is not very interesting, as CPK prefix has +# only one match. Create a dataset where scan on CPK prefix +# would produce multiple matches: +# +create table t1 (a int, b int, c int, filler char(100), primary key(a,b,c)); +insert into t1 select A.a, B.a, C.a, 'filler' from t0 A, t0 B, t0 C; + +insert into t1 values (11, 11, 11, 'filler'); +insert into t1 values (11, 11, 12, 'filler'); +insert into t1 values (11, 11, 13, 'filler'); +insert into t1 values (11, 22, 1234, 'filler'); +insert into t1 values (11, 33, 124, 'filler'); +insert into t1 values (11, 33, 125, 'filler'); + +create table t2 (a int, b int); +insert into t2 values (11,33), (11,22), (11,11); + +explain select * from t1, t2 where t1.a=t2.a and t1.b=t2.b; +select * from t1, t2 where t1.a=t2.a and t1.b=t2.b; + +set join_cache_level=0; +select * from t1, t2 where t1.a=t2.a and t1.b=t2.b; +set join_cache_level=6; + +drop table t1,t2; + +# +# Check that Index Condition Pushdown (BKA) actually works: +# + +# TODO + +# +# Check that record-check-func is done: +# + +set @@join_cache_level= @save_join_cache_level; +set storage_engine=@save_storage_engine; +drop table t0; + diff -urN --exclude='.*' maria-5.3-dsmrr-for-cpk-clean/r/innodb_mrr_cpk.result maria-5.3-dsmrr-for-cpk-noc/r/innodb_mrr_cpk.result --- maria-5.3-dsmrr-for-cpk-clean/r/innodb_mrr_cpk.result 1970-01-01 03:00:00.000000000 +0300 +++ maria-5.3-dsmrr-for-cpk-noc/r/innodb_mrr_cpk.result 2010-06-22 19:23:14.000000000 +0400 @@ -0,0 +1,122 @@ +drop table if exists t0,t1,t2,t3; +set @save_join_cache_level=@@join_cache_level; +set join_cache_level=6; +set @save_storage_engine=@@storage_engine; +set storage_engine=innodb; +create table t0(a int); +insert into t0 values (0),(1),(2),(3),(4),(5),(6),(7),(8),(9); +create table t1(a char(8), b char(8), filler char(100), primary key(a)); +show create table t1; +Table Create Table +t1 CREATE TABLE `t1` ( + `a` char(8) NOT NULL DEFAULT '', + `b` char(8) DEFAULT NULL, + `filler` char(100) DEFAULT NULL, + PRIMARY KEY (`a`) +) ENGINE=InnoDB DEFAULT CHARSET=latin1 +insert into t1 select +concat('a-', 1000 + A.a + B.a*10 + C.a*100, '=A'), +concat('b-', 1000 + A.a + B.a*10 + C.a*100, '=B'), +'filler' +from t0 A, t0 B, t0 C; +create table t2 (a char(8)); +insert into t2 values ('a-1010=A'), ('a-1030=A'), ('a-1020=A'); +This should use join buffer: +explain select * from t1, t2 where t1.a=t2.a; +id select_type table type possible_keys key key_len ref rows Extra +1 SIMPLE t2 ALL NULL NULL NULL NULL 3 +1 SIMPLE t1 eq_ref PRIMARY PRIMARY 8 test.t2.a 1 Using join buffer +This output must be sorted by value of t1.a: +select * from t1, t2 where t1.a=t2.a; +a b filler a +a-1010=A b-1010=B filler a-1010=A +a-1020=A b-1020=B filler a-1020=A +a-1030=A b-1030=B filler a-1030=A +drop table t1, t2; +create table t1( +a char(8) character set utf8, b int, filler char(100), +primary key(a,b) +); +insert into t1 select +concat('a-', 1000 + A.a + B.a*10 + C.a*100, '=A'), +1000 + A.a + B.a*10 + C.a*100, +'filler' +from t0 A, t0 B, t0 C; +create table t2 (a char(8) character set utf8, b int); +insert into t2 values ('a-1010=A', 1010), ('a-1030=A', 1030), ('a-1020=A', 1020); +explain select * from t1, t2 where t1.a=t2.a and t1.b=t2.b; +id select_type table type possible_keys key key_len ref rows Extra +1 SIMPLE t2 ALL NULL NULL NULL NULL 3 +1 SIMPLE t1 eq_ref PRIMARY PRIMARY 28 test.t2.a,test.t2.b 1 Using join buffer +select * from t1, t2 where t1.a=t2.a and t1.b=t2.b; +a b filler a b +a-1010=A 1010 filler a-1010=A 1010 +a-1020=A 1020 filler a-1020=A 1020 +a-1030=A 1030 filler a-1030=A 1030 +drop table t1, t2; +create table t1( +a varchar(8) character set utf8, b int, filler char(100), +primary key(a,b) +); +insert into t1 select +concat('a-', 1000 + A.a + B.a*10 + C.a*100, '=A'), +1000 + A.a + B.a*10 + C.a*100, +'filler' +from t0 A, t0 B, t0 C; +create table t2 (a char(8) character set utf8, b int); +insert into t2 values ('a-1010=A', 1010), ('a-1030=A', 1030), ('a-1020=A', 1020); +explain select * from t1, t2 where t1.a=t2.a and t1.b=t2.b; +id select_type table type possible_keys key key_len ref rows Extra +1 SIMPLE t2 ALL NULL NULL NULL NULL 3 +1 SIMPLE t1 eq_ref PRIMARY PRIMARY 30 test.t2.a,test.t2.b 1 Using index condition(BKA); Using join buffer +select * from t1, t2 where t1.a=t2.a and t1.b=t2.b; +a b filler a b +a-1010=A 1010 filler a-1010=A 1010 +a-1020=A 1020 filler a-1020=A 1020 +a-1030=A 1030 filler a-1030=A 1030 +explain select * from t1, t2 where t1.a=t2.a; +id select_type table type possible_keys key key_len ref rows Extra +1 SIMPLE t2 ALL NULL NULL NULL NULL 3 +1 SIMPLE t1 ref PRIMARY PRIMARY 26 test.t2.a 1 Using index condition(BKA); Using join buffer +select * from t1, t2 where t1.a=t2.a; +a b filler a b +a-1010=A 1010 filler a-1010=A 1010 +a-1020=A 1020 filler a-1020=A 1020 +a-1030=A 1030 filler a-1030=A 1030 +drop table t1, t2; +create table t1 (a int, b int, c int, filler char(100), primary key(a,b,c)); +insert into t1 select A.a, B.a, C.a, 'filler' from t0 A, t0 B, t0 C; +insert into t1 values (11, 11, 11, 'filler'); +insert into t1 values (11, 11, 12, 'filler'); +insert into t1 values (11, 11, 13, 'filler'); +insert into t1 values (11, 22, 1234, 'filler'); +insert into t1 values (11, 33, 124, 'filler'); +insert into t1 values (11, 33, 125, 'filler'); +create table t2 (a int, b int); +insert into t2 values (11,33), (11,22), (11,11); +explain select * from t1, t2 where t1.a=t2.a and t1.b=t2.b; +id select_type table type possible_keys key key_len ref rows Extra +1 SIMPLE t2 ALL NULL NULL NULL NULL 3 +1 SIMPLE t1 ref PRIMARY PRIMARY 8 test.t2.a,test.t2.b 1 Using join buffer +select * from t1, t2 where t1.a=t2.a and t1.b=t2.b; +a b c filler a b +11 11 11 filler 11 11 +11 11 12 filler 11 11 +11 11 13 filler 11 11 +11 22 1234 filler 11 22 +11 33 124 filler 11 33 +11 33 125 filler 11 33 +set join_cache_level=0; +select * from t1, t2 where t1.a=t2.a and t1.b=t2.b; +a b c filler a b +11 33 124 filler 11 33 +11 33 125 filler 11 33 +11 22 1234 filler 11 22 +11 11 11 filler 11 11 +11 11 12 filler 11 11 +11 11 13 filler 11 11 +set join_cache_level=6; +drop table t1,t2; +set @@join_cache_level= @save_join_cache_level; +set storage_engine=@save_storage_engine; +drop table t0; diff -urN --exclude='.*' maria-5.3-dsmrr-for-cpk-clean/sql/handler.h maria-5.3-dsmrr-for-cpk-noc/sql/handler.h --- maria-5.3-dsmrr-for-cpk-clean/sql/handler.h 2010-06-22 19:10:46.000000000 +0400 +++ maria-5.3-dsmrr-for-cpk-noc/sql/handler.h 2010-06-22 23:28:40.000000000 +0400 @@ -1168,9 +1168,9 @@ COST_VECT *cost); /* - The below two are not used (and not handled) in this milestone of this WL - entry because there seems to be no use for them at this stage of - implementation. + Indicates that all scanned ranges will be singlepoint (aka equality) ranges. + The ranges may not use the full key but all of them will use the same number + of key parts. */ #define HA_MRR_SINGLE_POINT 1 #define HA_MRR_FIXED_KEY 2 @@ -1752,9 +1752,10 @@ uint n_ranges, uint *bufsz, uint *flags, COST_VECT *cost); virtual ha_rows multi_range_read_info(uint keyno, uint n_ranges, uint keys, - uint *bufsz, uint *flags, COST_VECT *cost); + uint key_parts, uint *bufsz, + uint *flags, COST_VECT *cost); virtual int multi_range_read_init(RANGE_SEQ_IF *seq, void *seq_init_param, - uint n_ranges, uint mode, + uint n_ranges, uint mode, HANDLER_BUFFER *buf); virtual int multi_range_read_next(char **range_info); virtual int read_range_first(const key_range *start_key, diff -urN --exclude='.*' maria-5.3-dsmrr-for-cpk-clean/sql/multi_range_read.cc maria-5.3-dsmrr-for-cpk-noc/sql/multi_range_read.cc --- maria-5.3-dsmrr-for-cpk-clean/sql/multi_range_read.cc 2010-06-22 19:10:46.000000000 +0400 +++ maria-5.3-dsmrr-for-cpk-noc/sql/multi_range_read.cc 2010-06-22 23:28:40.000000000 +0400 @@ -1,4 +1,5 @@ #include "mysql_priv.h" +#include <my_bit.h> #include "sql_select.h" /**************************************************************************** @@ -136,10 +137,16 @@ */ ha_rows handler::multi_range_read_info(uint keyno, uint n_ranges, uint n_rows, - uint *bufsz, uint *flags, COST_VECT *cost) + uint key_parts, uint *bufsz, + uint *flags, COST_VECT *cost) { - *bufsz= 0; /* Default implementation doesn't need a buffer */ + /* + Currently we expect this function to be called only in preparation of scan + with HA_MRR_SINGLE_POINT property. + */ + DBUG_ASSERT(*flags | HA_MRR_SINGLE_POINT); + *bufsz= 0; /* Default implementation doesn't need a buffer */ *flags |= HA_MRR_USE_DEFAULT_IMPL; cost->zero(); @@ -316,25 +323,39 @@ { use_default_impl= TRUE; const int retval= - h->handler::multi_range_read_init(seq_funcs, seq_init_param, - n_ranges, mode, buf); + h->handler::multi_range_read_init(seq_funcs, seq_init_param, n_ranges, + mode, buf); DBUG_RETURN(retval); } - rowids_buf= buf->buffer; + mrr_buf= buf->buffer; is_mrr_assoc= !test(mode & HA_MRR_NO_ASSOCIATION); if (is_mrr_assoc) status_var_increment(table->in_use->status_var.ha_multi_range_read_init_count); - rowids_buf_end= buf->buffer_end; + mrr_buf_end= buf->buffer_end; + + if ((doing_cpk_scan= check_cpk_scan(h->active_index, mode))) + { + /* It's a DS-MRR/CPK scan */ + cpk_tuple_length= 0; /* dummy value telling it needs to be inited */ + cpk_have_range= FALSE; + use_default_impl= FALSE; + h->mrr_iter= seq_funcs->init(seq_init_param, n_ranges, mode); + h->mrr_funcs= *seq_funcs; + dsmrr_fill_buffer_cpk(); + if (dsmrr_eof) + buf->end_of_used_area= mrr_buf_last; + DBUG_RETURN(0); /* nothing could go wrong while filling the buffer */ + } + + /* In regular DS-MRR, buffer stores {rowid, range_id} pairs */ elem_size= h->ref_length + (int)is_mrr_assoc * sizeof(void*); - rowids_buf_last= rowids_buf + - ((rowids_buf_end - rowids_buf)/ elem_size)* - elem_size; - rowids_buf_end= rowids_buf_last; + mrr_buf_last= mrr_buf + ((mrr_buf_end - mrr_buf)/ elem_size)* elem_size; + mrr_buf_end= mrr_buf_last; - /* + /* There can be two cases: - This is the first call since index_init(), h2==NULL Need to setup h2 then. @@ -406,8 +427,8 @@ goto error; } - if (h2->handler::multi_range_read_init(seq_funcs, seq_init_param, n_ranges, - mode, buf) || + if (h2->handler::multi_range_read_init(seq_funcs, seq_init_param, n_ranges, + mode, buf) || dsmrr_fill_buffer()) { goto error; @@ -417,7 +438,7 @@ adjust *buf to indicate that the remaining buffer space will not be used. */ if (dsmrr_eof) - buf->end_of_used_area= rowids_buf_last; + buf->end_of_used_area= mrr_buf_last; /* h->inited == INDEX may occur when 'range checked for each record' is @@ -473,6 +494,9 @@ rowid and return. The function assumes that rowids buffer is empty when it is invoked. + + dsmrr_eof is set to indicate whether we've exhausted the list of ranges we're + scanning. @param h Table handler @@ -487,8 +511,8 @@ int res; DBUG_ENTER("DsMrr_impl::dsmrr_fill_buffer"); - rowids_buf_cur= rowids_buf; - while ((rowids_buf_cur < rowids_buf_end) && + mrr_buf_cur= mrr_buf; + while ((mrr_buf_cur < mrr_buf_end) && !(res= h2->handler::multi_range_read_next(&range_info))) { KEY_MULTI_RANGE *curr_range= &h2->handler::mrr_cur_range; @@ -498,13 +522,13 @@ /* Put rowid, or {rowid, range_id} pair into the buffer */ h2->position(table->record[0]); - memcpy(rowids_buf_cur, h2->ref, h2->ref_length); - rowids_buf_cur += h2->ref_length; + memcpy(mrr_buf_cur, h2->ref, h2->ref_length); + mrr_buf_cur += h2->ref_length; if (is_mrr_assoc) { - memcpy(rowids_buf_cur, &range_info, sizeof(void*)); - rowids_buf_cur += sizeof(void*); + memcpy(mrr_buf_cur, &range_info, sizeof(void*)); + mrr_buf_cur += sizeof(void*); } } @@ -514,16 +538,224 @@ /* Sort the buffer contents by rowid */ uint elem_size= h->ref_length + (int)is_mrr_assoc * sizeof(void*); - uint n_rowids= (rowids_buf_cur - rowids_buf) / elem_size; + uint n_rowids= (mrr_buf_cur - mrr_buf) / elem_size; - my_qsort2(rowids_buf, n_rowids, elem_size, (qsort2_cmp)rowid_cmp, + my_qsort2(mrr_buf, n_rowids, elem_size, (qsort2_cmp)rowid_cmp, (void*)h); - rowids_buf_last= rowids_buf_cur; - rowids_buf_cur= rowids_buf; + mrr_buf_last= mrr_buf_cur; + mrr_buf_cur= mrr_buf; DBUG_RETURN(0); } +/* + my_qsort2-compatible function to compare key tuples +*/ + +int DsMrr_impl::key_tuple_cmp(void* arg, uchar* key1, uchar* key2) +{ + DsMrr_impl *dsmrr= (DsMrr_impl*)arg; + TABLE *table= dsmrr->h->table; + + KEY_PART_INFO *part= table->key_info[table->s->primary_key].key_part; + uchar *key1_end= key1 + dsmrr->cpk_tuple_length; + + while (key1 < key1_end) + { + Field* f = part->field; + int len = part->store_length; + int res = f->cmp(key1, key2); + if (res) + return res; + key1 += len; + key2 += len; + part++; + } + return 0; +} + + +/* + DS-MRR/CPK: Fill the buffer with (lookup_tuple, range_id) pairs and sort + + SYNOPSIS + DsMrr_impl::dsmrr_fill_buffer_cpk() + + DESCRIPTION + DS-MRR/CPK: Fill the buffer with (lookup_tuple, range_id) pairs and sort + + dsmrr_eof is set to indicate whether we've exhausted the list of ranges + we're scanning. +*/ + +void DsMrr_impl::dsmrr_fill_buffer_cpk() +{ + int res; + KEY_MULTI_RANGE cur_range; + DBUG_ENTER("DsMrr_impl::dsmrr_fill_buffer_cpk"); + + mrr_buf_cur= mrr_buf; + while ((mrr_buf_cur < mrr_buf_end) && + !(res= h->mrr_funcs.next(h->mrr_iter, &cur_range))) + { + DBUG_ASSERT(cur_range.range_flag & EQ_RANGE); + DBUG_ASSERT(!cpk_tuple_length || + cpk_tuple_length == cur_range.start_key.length); + if (!cpk_tuple_length) + { + cpk_tuple_length= cur_range.start_key.length; + cpk_is_unique_scan= test(table->key_info[h->active_index].key_parts == + my_count_bits(cur_range.start_key.keypart_map)); + uint elem_size= cpk_tuple_length + (int)is_mrr_assoc * sizeof(void*); + mrr_buf_last= mrr_buf + ((mrr_buf_end - mrr_buf)/elem_size) * elem_size; + mrr_buf_end= mrr_buf_last; + } + + /* Put key, or {key, range_id} pair into the buffer */ + memcpy(mrr_buf_cur, cur_range.start_key.key, cpk_tuple_length); + mrr_buf_cur += cpk_tuple_length; + + if (is_mrr_assoc) + { + memcpy(mrr_buf_cur, &cur_range.ptr, sizeof(void*)); + mrr_buf_cur += sizeof(void*); + } + } + + dsmrr_eof= test(res); + + /* Sort the buffer contents by rowid */ + uint elem_size= cpk_tuple_length + (int)is_mrr_assoc * sizeof(void*); + uint n_rowids= (mrr_buf_cur - mrr_buf) / elem_size; + + my_qsort2(mrr_buf, n_rowids, elem_size, + (qsort2_cmp)DsMrr_impl::key_tuple_cmp, (void*)this); + mrr_buf_last= mrr_buf_cur; + mrr_buf_cur= mrr_buf; + DBUG_VOID_RETURN; +} + + +/* + DS-MRR/CPK: multi_range_read_next() function + + DESCRIPTION + DsMrr_impl::dsmrr_next_cpk() + range_info OUT identifier of range that the returned record belongs to + + DESCRIPTION + DS-MRR/CPK: multi_range_read_next() function. + This is similar to DsMrr_impl::dsmrr_next(), the differences are that + - we get records with index_read(), not with rnd_pos() + - we may get multiple records for one key (=element of the buffer) + - unlike dsmrr_fill_buffer(), dsmrr_fill_buffer_cpk() never fails. + + RETURN + 0 OK, next record was successfully read + HA_ERR_END_OF_FILE End of records + Other Some other error +*/ + +int DsMrr_impl::dsmrr_next_cpk(char **range_info) +{ + int res; + + while (cpk_have_range) + { + + if (h->mrr_funcs.skip_record && + h->mrr_funcs.skip_record(h->mrr_iter, cpk_saved_range_info, NULL)) + { + cpk_have_range= FALSE; + break; + } + + res= h->index_next_same(table->record[0], mrr_buf_cur, cpk_tuple_length); + + if (h->mrr_funcs.skip_index_tuple && + h->mrr_funcs.skip_index_tuple(h->mrr_iter, cpk_saved_range_info)) + continue; + + if (res != HA_ERR_END_OF_FILE) + { + if (is_mrr_assoc) + memcpy(range_info, &cpk_saved_range_info, sizeof(void*)); + return res; + } + + /* No more records in this range. Exit this loop and go get another range */ + cpk_have_range= FALSE; + } + + do + { + /* First, make sure we have a range at start of the buffer */ + if (mrr_buf_cur == mrr_buf_last) + { + if (dsmrr_eof) + { + res= HA_ERR_END_OF_FILE; + goto end; + } + dsmrr_fill_buffer_cpk(); + } + if (mrr_buf_cur == mrr_buf_last) + { + res= HA_ERR_END_OF_FILE; + goto end; + } + + /* Ok, got the range. Try making a lookup. */ + uchar *lookup_tuple= mrr_buf_cur; + mrr_buf_cur += cpk_tuple_length; + if (is_mrr_assoc) + { + memcpy(&cpk_saved_range_info, mrr_buf_cur, sizeof(void*)); + mrr_buf_cur += sizeof(void*) * test(is_mrr_assoc); + } + + if (h->mrr_funcs.skip_record && + h->mrr_funcs.skip_record(h->mrr_iter, cpk_saved_range_info, NULL)) + continue; + + res= h->index_read(table->record[0], lookup_tuple, cpk_tuple_length, + HA_READ_KEY_EXACT); + + /* + Check pushed index condition. Performance-wise, it does not make any + sense to put this call here (the above call has already accessed the full + record). That's the best I could do, though, because: + - ha_innobase doesn't support IndexConditionPushdown on clustered PK + - MRR interface doesn't allow the storage engine to refuse a pushed index + condition. + Having this call here is not fully harmless: EXPLAIN shows "pushed index + condition", which is technically true but doesn't bring the benefits that + one might expect. + */ + if (h->mrr_funcs.skip_index_tuple && + h->mrr_funcs.skip_index_tuple(h->mrr_iter, cpk_saved_range_info)) + continue; + + if (res && res != HA_ERR_END_OF_FILE) + goto end; + + if (!res) + { + memcpy(range_info, &cpk_saved_range_info, sizeof(void*)); + /* + Attempt reading more rows from this range only if there actually can + be multiple matches: + */ + cpk_have_range= !cpk_is_unique_scan; + break; + } + } while (true); + +end: + return res; +} + + /** DS-MRR implementation: multi_range_read_next() function */ @@ -536,10 +768,13 @@ if (use_default_impl) return h->handler::multi_range_read_next(range_info); + + if (doing_cpk_scan) + return dsmrr_next_cpk(range_info); do { - if (rowids_buf_cur == rowids_buf_last) + if (mrr_buf_cur == mrr_buf_last) { if (dsmrr_eof) { @@ -552,17 +787,17 @@ } /* return eof if there are no rowids in the buffer after re-fill attempt */ - if (rowids_buf_cur == rowids_buf_last) + if (mrr_buf_cur == mrr_buf_last) { res= HA_ERR_END_OF_FILE; goto end; } - rowid= rowids_buf_cur; + rowid= mrr_buf_cur; if (is_mrr_assoc) - memcpy(&cur_range_info, rowids_buf_cur + h->ref_length, sizeof(uchar**)); + memcpy(&cur_range_info, mrr_buf_cur + h->ref_length, sizeof(uchar**)); - rowids_buf_cur += h->ref_length + sizeof(void*) * test(is_mrr_assoc); + mrr_buf_cur += h->ref_length + sizeof(void*) * test(is_mrr_assoc); if (h2->mrr_funcs.skip_record && h2->mrr_funcs.skip_record(h2->mrr_iter, (char *) cur_range_info, rowid)) continue; @@ -582,7 +817,8 @@ /** DS-MRR implementation: multi_range_read_info() function */ -ha_rows DsMrr_impl::dsmrr_info(uint keyno, uint n_ranges, uint rows, +ha_rows DsMrr_impl::dsmrr_info(uint keyno, uint n_ranges, uint rows, + uint key_parts, uint *bufsz, uint *flags, COST_VECT *cost) { ha_rows res; @@ -590,8 +826,8 @@ uint def_bufsz= *bufsz; /* Get cost/flags/mem_usage of default MRR implementation */ - res= h->handler::multi_range_read_info(keyno, n_ranges, rows, &def_bufsz, - &def_flags, cost); + res= h->handler::multi_range_read_info(keyno, n_ranges, rows, key_parts, + &def_bufsz, &def_flags, cost); DBUG_ASSERT(!res); if ((*flags & HA_MRR_USE_DEFAULT_IMPL) || @@ -683,7 +919,33 @@ return FALSE; } -/** + +/* + Check if key/flags allow DS-MRR/CPK strategy to be used + + SYNOPSIS + DsMrr_impl::check_cpk_scan() + keyno Index that will be used + mrr_flags + + DESCRIPTION + Check if key/flags allow DS-MRR/CPK strategy to be used. + + RETURN + TRUE DS-MRR/CPK should be used + FALSE Otherwise +*/ + +bool DsMrr_impl::check_cpk_scan(uint keyno, uint mrr_flags) +{ + return test((mrr_flags & HA_MRR_SINGLE_POINT) && + !(mrr_flags & HA_MRR_SORTED) && + keyno == table->s->primary_key && + h->primary_key_is_clustered()); +} + + +/* DS-MRR Internals: Choose between Default MRR implementation and DS-MRR Make the choice between using Default MRR implementation and DS-MRR. @@ -706,14 +968,18 @@ @retval FALSE DS-MRR implementation should be used */ + bool DsMrr_impl::choose_mrr_impl(uint keyno, ha_rows rows, uint *flags, uint *bufsz, COST_VECT *cost) { COST_VECT dsmrr_cost; bool res; THD *thd= current_thd; + + doing_cpk_scan= check_cpk_scan(keyno, *flags); if (thd->variables.optimizer_use_mrr == 2 || *flags & HA_MRR_INDEX_ONLY || - (keyno == table->s->primary_key && h->primary_key_is_clustered()) || + (keyno == table->s->primary_key && h->primary_key_is_clustered() && + !doing_cpk_scan) || key_uses_partial_cols(table, keyno)) { /* Use the default implementation */ diff -urN --exclude='.*' maria-5.3-dsmrr-for-cpk-clean/sql/multi_range_read.h maria-5.3-dsmrr-for-cpk-noc/sql/multi_range_read.h --- maria-5.3-dsmrr-for-cpk-clean/sql/multi_range_read.h 2010-06-22 19:10:46.000000000 +0400 +++ maria-5.3-dsmrr-for-cpk-noc/sql/multi_range_read.h 2010-06-22 23:28:40.000000000 +0400 @@ -1,16 +1,76 @@ /* - This file contains declarations for - - Disk-Sweep MultiRangeRead (DS-MRR) implementation + This file contains declarations for Disk-Sweep MultiRangeRead (DS-MRR) + implementation */ /** - A Disk-Sweep MRR interface implementation + A Disk-Sweep implementation of MRR Interface (DS-MRR for short) - This implementation makes range (and, in the future, 'ref') scans to read - table rows in disk sweeps. - - Currently it is used by MyISAM and InnoDB. Potentially it can be used with - any table handler that has non-clustered indexes and on-disk rows. + This is a "plugin"(*) for storage engines that allows make index scans + read table rows in rowid order. For disk-based storage engines, this is + faster than reading table rows in whatever-SQL-layer-makes-calls-in order. + + (*) - only conceptually. No dynamic loading or binary compatibility of any + kind. + + General scheme of things: + + SQL Layer code + | | | + -v---v---v---- handler->multi_range_read_XXX() function calls + | | | + ____________________________________ + / DS-MRR module \ + | (scan indexes, order rowids, do | + | full record reads in rowid order) | + \____________________________________/ + | | | + -|---|---|----- handler->read_range_first()/read_range_next(), + | | | handler->index_read(), handler->rnd_pos() calls. + | | | + v v v + Storage engine internals + + Currently DS-MRR is used by MyISAM, InnoDB/XtraDB and Maria storage engines. + Potentially it can be used with any table handler that has disk-based data + storage and has better performance when reading data in rowid order. +*/ + + +/* + DS-MRR implementation for one table. Create/use one object of this class for + each ha_{myisam/innobase/etc} object. That object will be further referred to + as "the handler" + + There are actually three strategies + S1. Bypass DS-MRR, pass all calls to default implementation (i.e. to + MRR-to-non-MRR calls converter) + S2. Regular DS-MRR + S3. DS-MRR/CPK for doing scans on clustered primary keys. + + S1 is used for cases which DS-MRR is unable to handle for some reason. + + S2 is the actual DS-MRR. The basic algorithm is as follows: + 1. Scan the index (and only index, that is, with HA_EXTRA_KEYREAD on) and + fill the buffer with {rowid, range_id} pairs + 2. Sort the buffer by rowid + 3. for each {rowid, range_id} pair in the buffer + get record by rowid and return the {record, range_id} pair + 4. Repeat the above steps until we've exhausted the list of ranges we're + scanning. + + S3 is the variant of DS-MRR for use with clustered primary keys (or any + clustered index). The idea is that in clustered index it is sufficient to + access the index in index order, and we don't need an intermediate steps to + get rowid (like step #1 in S2). + + DS-MRR/CPK's basic algorithm is as follows: + 1. Collect a number of ranges (=lookup keys) + 2. Sort them so that they follow in index order. + 3. for each {lookup_key, range_id} pair in the buffer + get record(s) matching the lookup key and return {record, range_id} pairs + 4. Repeat the above steps until we've exhausted the list of ranges we're + scanning. */ class DsMrr_impl @@ -21,21 +81,38 @@ DsMrr_impl() : h2(NULL) {}; + void init(handler *h_arg, TABLE *table_arg) + { + h= h_arg; + table= table_arg; + } + int dsmrr_init(handler *h, RANGE_SEQ_IF *seq_funcs, void *seq_init_param, + uint n_ranges, uint mode, HANDLER_BUFFER *buf); + void dsmrr_close(); + int dsmrr_next(char **range_info); + + ha_rows dsmrr_info(uint keyno, uint n_ranges, uint keys, uint key_parts, + uint *bufsz, uint *flags, COST_VECT *cost); + + ha_rows dsmrr_info_const(uint keyno, RANGE_SEQ_IF *seq, + void *seq_init_param, uint n_ranges, uint *bufsz, + uint *flags, COST_VECT *cost); +private: /* The "owner" handler object (the one that calls dsmrr_XXX functions. It is used to retrieve full table rows by calling rnd_pos(). */ handler *h; TABLE *table; /* Always equal to h->table */ -private: + /* Secondary handler object. It is used for scanning the index */ handler *h2; /* Buffer to store rowids, or (rowid, range_id) pairs */ - uchar *rowids_buf; - uchar *rowids_buf_cur; /* Current position when reading/writing */ - uchar *rowids_buf_last; /* When reading: end of used buffer space */ - uchar *rowids_buf_end; /* End of the buffer */ + uchar *mrr_buf; + uchar *mrr_buf_cur; /* Current position when reading/writing */ + uchar *mrr_buf_last; /* When reading: end of used buffer space */ + uchar *mrr_buf_end; /* End of the buffer */ bool dsmrr_eof; /* TRUE <=> We have reached EOF when reading index tuples */ @@ -43,28 +120,31 @@ bool is_mrr_assoc; bool use_default_impl; /* TRUE <=> shortcut all calls to default MRR impl */ -public: - void init(handler *h_arg, TABLE *table_arg) - { - h= h_arg; - table= table_arg; - } - int dsmrr_init(handler *h, RANGE_SEQ_IF *seq_funcs, void *seq_init_param, - uint n_ranges, uint mode, HANDLER_BUFFER *buf); - void dsmrr_close(); - int dsmrr_fill_buffer(); - int dsmrr_next(char **range_info); - ha_rows dsmrr_info(uint keyno, uint n_ranges, uint keys, uint *bufsz, - uint *flags, COST_VECT *cost); + bool doing_cpk_scan; /* TRUE <=> DS-MRR/CPK variant is used */ + + /** DS-MRR/CPK variables start */ + + /* Length of lookup tuple being used, in bytes */ + uint cpk_tuple_length; + /* + TRUE <=> We're scanning on a full primary key (and not on prefix), and so + can get max. one match for each key + */ + bool cpk_is_unique_scan; + /* TRUE<=> we're in a middle of enumerating records from a range */ + bool cpk_have_range; + /* Valid if cpk_have_range==TRUE: range_id of the range we're enumerating */ + char *cpk_saved_range_info; - ha_rows dsmrr_info_const(uint keyno, RANGE_SEQ_IF *seq, - void *seq_init_param, uint n_ranges, uint *bufsz, - uint *flags, COST_VECT *cost); -private: bool choose_mrr_impl(uint keyno, ha_rows rows, uint *flags, uint *bufsz, COST_VECT *cost); bool get_disk_sweep_mrr_cost(uint keynr, ha_rows rows, uint flags, uint *buffer_size, COST_VECT *cost); + bool check_cpk_scan(uint keyno, uint mrr_flags); + static int key_tuple_cmp(void* arg, uchar* key1, uchar* key2); + int dsmrr_fill_buffer(); + void dsmrr_fill_buffer_cpk(); + int dsmrr_next_cpk(char **range_info); }; diff -urN --exclude='.*' maria-5.3-dsmrr-for-cpk-clean/sql/opt_range.cc maria-5.3-dsmrr-for-cpk-noc/sql/opt_range.cc --- maria-5.3-dsmrr-for-cpk-clean/sql/opt_range.cc 2010-06-22 19:10:46.000000000 +0400 +++ maria-5.3-dsmrr-for-cpk-noc/sql/opt_range.cc 2010-06-22 23:28:40.000000000 +0400 @@ -8006,6 +8006,7 @@ quick->mrr_buf_size= thd->variables.mrr_buff_size; if (table->file->multi_range_read_info(quick->index, 1, (uint)records, + uint(-1), &quick->mrr_buf_size, &quick->mrr_flags, &cost)) goto err; diff -urN --exclude='.*' maria-5.3-dsmrr-for-cpk-clean/sql/sql_join_cache.cc maria-5.3-dsmrr-for-cpk-noc/sql/sql_join_cache.cc --- maria-5.3-dsmrr-for-cpk-clean/sql/sql_join_cache.cc 2010-06-22 19:10:46.000000000 +0400 +++ maria-5.3-dsmrr-for-cpk-noc/sql/sql_join_cache.cc 2010-06-22 23:28:40.000000000 +0400 @@ -2376,8 +2376,8 @@ */ if (!file->inited) file->ha_index_init(join_tab->ref.key, 1); - if ((error= file->multi_range_read_init(seq_funcs, (void*) this, ranges, - mrr_mode, &mrr_buff))) + if ((error= file->multi_range_read_init(seq_funcs, (void*) this, ranges, + mrr_mode, &mrr_buff))) rc= error < 0 ? NESTED_LOOP_NO_MORE_ROWS: NESTED_LOOP_ERROR; return rc; diff -urN --exclude='.*' maria-5.3-dsmrr-for-cpk-clean/sql/sql_select.cc maria-5.3-dsmrr-for-cpk-noc/sql/sql_select.cc --- maria-5.3-dsmrr-for-cpk-clean/sql/sql_select.cc 2010-06-22 19:10:46.000000000 +0400 +++ maria-5.3-dsmrr-for-cpk-noc/sql/sql_select.cc 2010-06-22 19:06:54.000000000 +0400 @@ -7318,10 +7318,11 @@ case JT_EQ_REF: if (cache_level <= 4) return 0; - flags= HA_MRR_NO_NULL_ENDPOINTS; + flags= HA_MRR_NO_NULL_ENDPOINTS | HA_MRR_SINGLE_POINT; if (tab->table->covering_keys.is_set(tab->ref.key)) flags|= HA_MRR_INDEX_ONLY; rows= tab->table->file->multi_range_read_info(tab->ref.key, 10, 20, + tab->ref.key_parts, &bufsz, &flags, &cost); if ((rows != HA_POS_ERROR) && !(flags & HA_MRR_USE_DEFAULT_IMPL) && (!(flags & HA_MRR_NO_ASSOCIATION) || cache_level > 6) && diff -urN --exclude='.*' maria-5.3-dsmrr-for-cpk-clean/storage/maria/ha_maria.cc maria-5.3-dsmrr-for-cpk-noc/storage/maria/ha_maria.cc --- maria-5.3-dsmrr-for-cpk-clean/storage/maria/ha_maria.cc 2010-06-22 19:10:46.000000000 +0400 +++ maria-5.3-dsmrr-for-cpk-noc/storage/maria/ha_maria.cc 2010-06-22 23:28:40.000000000 +0400 @@ -3501,8 +3501,8 @@ ***************************************************************************/ int ha_maria::multi_range_read_init(RANGE_SEQ_IF *seq, void *seq_init_param, - uint n_ranges, uint mode, - HANDLER_BUFFER *buf) + uint n_ranges, uint mode, + HANDLER_BUFFER *buf) { return ds_mrr.dsmrr_init(this, seq, seq_init_param, n_ranges, mode, buf); } @@ -3528,11 +3528,11 @@ } ha_rows ha_maria::multi_range_read_info(uint keyno, uint n_ranges, uint keys, - uint *bufsz, uint *flags, - COST_VECT *cost) + uint key_parts, uint *bufsz, + uint *flags, COST_VECT *cost) { ds_mrr.init(this, table); - return ds_mrr.dsmrr_info(keyno, n_ranges, keys, bufsz, flags, cost); + return ds_mrr.dsmrr_info(keyno, n_ranges, keys, key_parts, bufsz, flags, cost); } /* MyISAM MRR implementation ends */ diff -urN --exclude='.*' maria-5.3-dsmrr-for-cpk-clean/storage/maria/ha_maria.h maria-5.3-dsmrr-for-cpk-noc/storage/maria/ha_maria.h --- maria-5.3-dsmrr-for-cpk-clean/storage/maria/ha_maria.h 2010-06-22 19:10:46.000000000 +0400 +++ maria-5.3-dsmrr-for-cpk-noc/storage/maria/ha_maria.h 2010-06-22 23:28:40.000000000 +0400 @@ -181,7 +181,8 @@ uint n_ranges, uint *bufsz, uint *flags, COST_VECT *cost); ha_rows multi_range_read_info(uint keyno, uint n_ranges, uint keys, - uint *bufsz, uint *flags, COST_VECT *cost); + uint key_parts, uint *bufsz, + uint *flags, COST_VECT *cost); /* Index condition pushdown implementation */ Item *idx_cond_push(uint keyno, Item* idx_cond); diff -urN --exclude='.*' maria-5.3-dsmrr-for-cpk-clean/storage/myisam/ha_myisam.cc maria-5.3-dsmrr-for-cpk-noc/storage/myisam/ha_myisam.cc --- maria-5.3-dsmrr-for-cpk-clean/storage/myisam/ha_myisam.cc 2010-06-22 19:10:46.000000000 +0400 +++ maria-5.3-dsmrr-for-cpk-noc/storage/myisam/ha_myisam.cc 2010-06-22 23:28:40.000000000 +0400 @@ -2244,11 +2244,11 @@ } ha_rows ha_myisam::multi_range_read_info(uint keyno, uint n_ranges, uint keys, - uint *bufsz, uint *flags, - COST_VECT *cost) + uint key_parts, uint *bufsz, + uint *flags, COST_VECT *cost) { ds_mrr.init(this, table); - return ds_mrr.dsmrr_info(keyno, n_ranges, keys, bufsz, flags, cost); + return ds_mrr.dsmrr_info(keyno, n_ranges, keys, key_parts, bufsz, flags, cost); } /* MyISAM MRR implementation ends */ diff -urN --exclude='.*' maria-5.3-dsmrr-for-cpk-clean/storage/myisam/ha_myisam.h maria-5.3-dsmrr-for-cpk-noc/storage/myisam/ha_myisam.h --- maria-5.3-dsmrr-for-cpk-clean/storage/myisam/ha_myisam.h 2010-06-22 19:10:46.000000000 +0400 +++ maria-5.3-dsmrr-for-cpk-noc/storage/myisam/ha_myisam.h 2010-06-22 23:28:40.000000000 +0400 @@ -169,7 +169,8 @@ uint n_ranges, uint *bufsz, uint *flags, COST_VECT *cost); ha_rows multi_range_read_info(uint keyno, uint n_ranges, uint keys, - uint *bufsz, uint *flags, COST_VECT *cost); + uint key_parts, uint *bufsz, + uint *flags, COST_VECT *cost); /* Index condition pushdown implementation */ Item *idx_cond_push(uint keyno, Item* idx_cond); diff -urN --exclude='.*' maria-5.3-dsmrr-for-cpk-clean/storage/xtradb/handler/ha_innodb.cc maria-5.3-dsmrr-for-cpk-noc/storage/xtradb/handler/ha_innodb.cc --- maria-5.3-dsmrr-for-cpk-clean/storage/xtradb/handler/ha_innodb.cc 2010-06-22 19:10:46.000000000 +0400 +++ maria-5.3-dsmrr-for-cpk-noc/storage/xtradb/handler/ha_innodb.cc 2010-06-22 23:28:40.000000000 +0400 @@ -11025,7 +11025,8 @@ */ int ha_innobase::multi_range_read_init(RANGE_SEQ_IF *seq, void *seq_init_param, - uint n_ranges, uint mode, HANDLER_BUFFER *buf) + uint n_ranges, uint mode, + HANDLER_BUFFER *buf) { return ds_mrr.dsmrr_init(this, seq, seq_init_param, n_ranges, mode, buf); } @@ -11052,12 +11053,13 @@ return res; } -ha_rows ha_innobase::multi_range_read_info(uint keyno, uint n_ranges, - uint keys, uint *bufsz, +ha_rows ha_innobase::multi_range_read_info(uint keyno, uint n_ranges, uint keys, + uint key_parts, uint *bufsz, uint *flags, COST_VECT *cost) { ds_mrr.init(this, table); - ha_rows res= ds_mrr.dsmrr_info(keyno, n_ranges, keys, bufsz, flags, cost); + ha_rows res= ds_mrr.dsmrr_info(keyno, n_ranges, keys, key_parts, bufsz, + flags, cost); return res; } diff -urN --exclude='.*' maria-5.3-dsmrr-for-cpk-clean/storage/xtradb/handler/ha_innodb.h maria-5.3-dsmrr-for-cpk-noc/storage/xtradb/handler/ha_innodb.h --- maria-5.3-dsmrr-for-cpk-clean/storage/xtradb/handler/ha_innodb.h 2010-06-22 19:10:46.000000000 +0400 +++ maria-5.3-dsmrr-for-cpk-noc/storage/xtradb/handler/ha_innodb.h 2010-06-22 23:28:40.000000000 +0400 @@ -217,7 +217,8 @@ uint n_ranges, uint *bufsz, uint *flags, COST_VECT *cost); ha_rows multi_range_read_info(uint keyno, uint n_ranges, uint keys, - uint *bufsz, uint *flags, COST_VECT *cost); + uint key_parts, uint *bufsz, + uint *flags, COST_VECT *cost); DsMrr_impl ds_mrr; Item *idx_cond_push(uint keyno, Item* idx_cond); BR Sergey -- Sergey Petrunia, Software Developer Monty Program AB, http://askmonty.org Blog: http://s.petrunia.net/blog
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Sergey Petrunya