-- source include/have_innodb.inc --disable_warnings drop table if exists prefixinno; --enable_warnings set global innodb_prefix_index_cluster_optimization = ON; show variables like 'innodb_prefix_index_cluster_optimization'; --echo # Create a table with a large varchar field that we index the prefix --echo # of and ensure we only trigger cluster lookups when we expect it. create table prefixinno ( id int not null, fake_id int not null, bigfield varchar(4096), primary key(id), index bigfield_idx (bigfield(32)), index fake_id_bigfield_prefix (fake_id, bigfield(32)) ) engine=innodb; insert into prefixinno values (1, 1001, repeat('a', 1)), (8, 1008, repeat('b', 8)), (24, 1024, repeat('c', 24)), (31, 1031, repeat('d', 31)), (32, 1032, repeat('x', 32)), (33, 1033, repeat('y', 33)), (128, 1128, repeat('z', 128)); select * from prefixinno; let $show_count_statement = show status like 'innodb_secondary_index_triggered_cluster_reads'; let $show_opt_statement = show status like 'innodb_secondary_index_triggered_cluster_reads_avoided'; --echo # Baseline sanity check: 0, 0. let $base_count = query_get_value($show_count_statement, Value, 1); let $base_opt = query_get_value($show_opt_statement, Value, 1); select "no-op query"; let $count = query_get_value($show_count_statement, Value, 1); let $opt = query_get_value($show_opt_statement, Value, 1); --disable_query_log eval select $count - $base_count into @cluster_lookups; eval select $opt - $base_opt into @cluster_lookups_avoided; --enable_query_log select @cluster_lookups; select @cluster_lookups_avoided; --echo # Eligible for optimization. let $base_count = query_get_value($show_count_statement, Value, 1); let $base_opt = query_get_value($show_opt_statement, Value, 1); select id, bigfield from prefixinno where bigfield = repeat('d', 31); let $count = query_get_value($show_count_statement, Value, 1); let $opt = query_get_value($show_opt_statement, Value, 1); --disable_query_log eval select $count - $base_count into @cluster_lookups; eval select $opt - $base_opt into @cluster_lookups_avoided; --enable_query_log select @cluster_lookups; select @cluster_lookups_avoided; --echo # Eligible for optimization, access via fake_id only. let $base_count = query_get_value($show_count_statement, Value, 1); let $base_opt = query_get_value($show_opt_statement, Value, 1); select id, bigfield from prefixinno where fake_id = 1031; let $count = query_get_value($show_count_statement, Value, 1); let $opt = query_get_value($show_opt_statement, Value, 1); --disable_query_log eval select $count - $base_count into @cluster_lookups; eval select $opt - $base_opt into @cluster_lookups_avoided; --enable_query_log select @cluster_lookups; select @cluster_lookups_avoided; --echo # Not eligible for optimization, access via fake_id of big row. let $base_count = query_get_value($show_count_statement, Value, 1); let $base_opt = query_get_value($show_opt_statement, Value, 1); select id, bigfield from prefixinno where fake_id = 1033; let $count = query_get_value($show_count_statement, Value, 1); let $opt = query_get_value($show_opt_statement, Value, 1); --disable_query_log eval select $count - $base_count into @cluster_lookups; eval select $opt - $base_opt into @cluster_lookups_avoided; --enable_query_log select @cluster_lookups; select @cluster_lookups_avoided; --echo # Not eligible for optimization. let $base_count = query_get_value($show_count_statement, Value, 1); let $base_opt = query_get_value($show_opt_statement, Value, 1); select id, bigfield from prefixinno where bigfield = repeat('x', 32); let $count = query_get_value($show_count_statement, Value, 1); let $opt = query_get_value($show_opt_statement, Value, 1); --disable_query_log eval select $count - $base_count into @cluster_lookups; eval select $opt - $base_opt into @cluster_lookups_avoided; --enable_query_log select @cluster_lookups; select @cluster_lookups_avoided; --echo # Not eligible for optimization. let $base_count = query_get_value($show_count_statement, Value, 1); let $base_opt = query_get_value($show_opt_statement, Value, 1); select id, bigfield from prefixinno where bigfield = repeat('y', 33); let $count = query_get_value($show_count_statement, Value, 1); let $opt = query_get_value($show_opt_statement, Value, 1); --disable_query_log eval select $count - $base_count into @cluster_lookups; eval select $opt - $base_opt into @cluster_lookups_avoided; --enable_query_log select @cluster_lookups; select @cluster_lookups_avoided; --echo # Eligible, should not increment lookup counter. let $base_count = query_get_value($show_count_statement, Value, 1); let $base_opt = query_get_value($show_opt_statement, Value, 1); select id, bigfield from prefixinno where bigfield = repeat('b', 8); let $count = query_get_value($show_count_statement, Value, 1); let $opt = query_get_value($show_opt_statement, Value, 1); --disable_query_log eval select $count - $base_count into @cluster_lookups; eval select $opt - $base_opt into @cluster_lookups_avoided; --enable_query_log select @cluster_lookups; select @cluster_lookups_avoided; --echo # Eligible, should not increment lookup counter. let $base_count = query_get_value($show_count_statement, Value, 1); let $base_opt = query_get_value($show_opt_statement, Value, 1); select id, bigfield from prefixinno where bigfield = repeat('c', 24); let $count = query_get_value($show_count_statement, Value, 1); let $opt = query_get_value($show_opt_statement, Value, 1); --disable_query_log eval select $count - $base_count into @cluster_lookups; eval select $opt - $base_opt into @cluster_lookups_avoided; --enable_query_log select @cluster_lookups; select @cluster_lookups_avoided; --echo # Should increment lookup counter. let $base_count = query_get_value($show_count_statement, Value, 1); let $base_opt = query_get_value($show_opt_statement, Value, 1); select id, bigfield from prefixinno where bigfield = repeat('z', 128); let $count = query_get_value($show_count_statement, Value, 1); let $opt = query_get_value($show_opt_statement, Value, 1); --disable_query_log eval select $count - $base_count into @cluster_lookups; eval select $opt - $base_opt into @cluster_lookups_avoided; --enable_query_log select @cluster_lookups; select @cluster_lookups_avoided; --echo # Disable optimization, confirm we still increment counter. let $base_count = query_get_value($show_count_statement, Value, 1); let $base_opt = query_get_value($show_opt_statement, Value, 1); set global innodb_prefix_index_cluster_optimization = OFF; select id, bigfield from prefixinno where fake_id = 1033; let $count = query_get_value($show_count_statement, Value, 1); let $opt = query_get_value($show_opt_statement, Value, 1); --disable_query_log eval select $count - $base_count into @cluster_lookups; eval select $opt - $base_opt into @cluster_lookups_avoided; --enable_query_log select @cluster_lookups; select @cluster_lookups_avoided; drop table prefixinno; --echo # Multi-byte handling case set global innodb_prefix_index_cluster_optimization = ON; SET NAMES utf8mb4; CREATE TABLE t1( f1 varchar(10) CHARACTER SET UTF8MB4 COLLATE UTF8MB4_BIN, INDEX (f1(3)))ENGINE=INNODB; INSERT INTO t1 VALUES('a'), ('cccc'), ('až'), ('cčc'), ('ggᵷg'), ('¢¢'); INSERT INTO t1 VALUES('தமிழ்'), ('🐱🌑'), ('🌒'), ('🌑'); INSERT INTO t1 VALUES('😊me'), ('eu€'), ('ls¢'); --echo # Eligible - record length is shorter than prefix let $base_count = query_get_value($show_count_statement, Value, 1); let $base_opt = query_get_value($show_opt_statement, Value, 1); SELECT f1 FROM t1 FORCE INDEX (`f1`) WHERE f1 = 'a'; let $count = query_get_value($show_count_statement, Value, 1); let $opt = query_get_value($show_opt_statement, Value, 1); --disable_query_log eval set @cluster_lookups = $count - $base_count; eval set @cluster_lookups_avoided = $opt - $base_opt; --enable_query_log select @cluster_lookups; select @cluster_lookups_avoided; --echo # Not eligible - record length longer than prefix length let $base_count = query_get_value($show_count_statement, Value, 1); let $base_opt = query_get_value($show_opt_statement, Value, 1); SELECT f1 FROM t1 FORCE INDEX (`f1`) WHERE f1 like 'c%'; let $count = query_get_value($show_count_statement, Value, 1); let $opt = query_get_value($show_opt_statement, Value, 1); --disable_query_log eval set @cluster_lookups = $count - $base_count; eval set @cluster_lookups_avoided = $opt - $base_opt; --enable_query_log select @cluster_lookups; select @cluster_lookups_avoided; --echo # Eligible - record length shorter than prefix length let $base_count = query_get_value($show_count_statement, Value, 1); let $base_opt = query_get_value($show_opt_statement, Value, 1); SELECT f1 FROM t1 FORCE INDEX (`f1`) WHERE f1 = 'až'; let $count = query_get_value($show_count_statement, Value, 1); let $opt = query_get_value($show_opt_statement, Value, 1); --disable_query_log eval set @cluster_lookups = $count - $base_count; eval set @cluster_lookups_avoided = $opt - $base_opt; --enable_query_log select @cluster_lookups; select @cluster_lookups_avoided; --echo # Not eligible - record length longer than prefix length let $base_count = query_get_value($show_count_statement, Value, 1); let $base_opt = query_get_value($show_opt_statement, Value, 1); SELECT f1 FROM t1 FORCE INDEX (`f1`) WHERE f1 = 'தமிழ்'; let $count = query_get_value($show_count_statement, Value, 1); let $opt = query_get_value($show_opt_statement, Value, 1); --disable_query_log eval set @cluster_lookups = $count - $base_count; eval set @cluster_lookups_avoided = $opt - $base_opt; --enable_query_log select @cluster_lookups; select @cluster_lookups_avoided; --echo # Not eligible - record length longer than prefix length let $base_count = query_get_value($show_count_statement, Value, 1); let $base_opt = query_get_value($show_opt_statement, Value, 1); SELECT f1 FROM t1 FORCE INDEX (`f1`) WHERE f1 like 'ggᵷ%'; let $count = query_get_value($show_count_statement, Value, 1); let $opt = query_get_value($show_opt_statement, Value, 1); --disable_query_log eval set @cluster_lookups = $count - $base_count; eval set @cluster_lookups_avoided = $opt - $base_opt; --enable_query_log select @cluster_lookups; select @cluster_lookups_avoided; --echo # Not eligible - record length longer than prefix length let $base_count = query_get_value($show_count_statement, Value, 1); let $base_opt = query_get_value($show_opt_statement, Value, 1); SELECT f1 FROM t1 FORCE INDEX (`f1`) WHERE f1 like '😊%'; let $count = query_get_value($show_count_statement, Value, 1); let $opt = query_get_value($show_opt_statement, Value, 1); --disable_query_log eval set @cluster_lookups = $count - $base_count; eval set @cluster_lookups_avoided = $opt - $base_opt; --enable_query_log select @cluster_lookups; select @cluster_lookups_avoided; --echo # Not eligible - record length longer than prefix length let $base_count = query_get_value($show_count_statement, Value, 1); let $base_opt = query_get_value($show_opt_statement, Value, 1); SELECT f1 FROM t1 FORCE INDEX (`f1`) WHERE f1 = 'ls¢'; let $count = query_get_value($show_count_statement, Value, 1); let $opt = query_get_value($show_opt_statement, Value, 1); --disable_query_log eval set @cluster_lookups = $count - $base_count; eval set @cluster_lookups_avoided = $opt - $base_opt; --enable_query_log select @cluster_lookups; select @cluster_lookups_avoided; --echo # Eligible - record length shorter than prefix length let $base_count = query_get_value($show_count_statement, Value, 1); let $base_opt = query_get_value($show_opt_statement, Value, 1); SELECT f1 FROM t1 FORCE INDEX (`f1`) WHERE f1 like '¢¢%'; let $count = query_get_value($show_count_statement, Value, 1); let $opt = query_get_value($show_opt_statement, Value, 1); --disable_query_log eval set @cluster_lookups = $count - $base_count; eval set @cluster_lookups_avoided = $opt - $base_opt; --enable_query_log select @cluster_lookups; select @cluster_lookups_avoided; --echo # Eligible - record length shorter than prefix length let $base_count = query_get_value($show_count_statement, Value, 1); let $base_opt = query_get_value($show_opt_statement, Value, 1); SELECT f1 FROM t1 FORCE INDEX (`f1`) WHERE f1 like '🐱🌑%'; let $count = query_get_value($show_count_statement, Value, 1); let $opt = query_get_value($show_opt_statement, Value, 1); --disable_query_log eval set @cluster_lookups = $count - $base_count; eval set @cluster_lookups_avoided = $opt - $base_opt; --enable_query_log select @cluster_lookups; select @cluster_lookups_avoided; --echo # Not eligible - record length longer than prefix length let $base_count = query_get_value($show_count_statement, Value, 1); let $base_opt = query_get_value($show_opt_statement, Value, 1); SELECT f1 FROM t1 FORCE INDEX (`f1`) WHERE f1 like '🌑%'; let $count = query_get_value($show_count_statement, Value, 1); let $opt = query_get_value($show_opt_statement, Value, 1); --disable_query_log eval set @cluster_lookups = $count - $base_count; eval set @cluster_lookups_avoided = $opt - $base_opt; --enable_query_log select @cluster_lookups; select @cluster_lookups_avoided; --echo # Not eligible - record length longer than prefix length let $base_count = query_get_value($show_count_statement, Value, 1); let $base_opt = query_get_value($show_opt_statement, Value, 1); SELECT f1 FROM t1 FORCE INDEX (`f1`) WHERE f1 like '🌒%'; let $count = query_get_value($show_count_statement, Value, 1); let $opt = query_get_value($show_opt_statement, Value, 1); --disable_query_log eval set @cluster_lookups = $count - $base_count; eval set @cluster_lookups_avoided = $opt - $base_opt; --enable_query_log select @cluster_lookups; select @cluster_lookups_avoided; DROP TABLE t1; --echo # Multi-byte with minimum character length > 1 bytes CREATE TABLE t1( f1 varchar(10) CHARACTER SET UTF16 COLLATE UTF16_BIN, INDEX (f1(3)))ENGINE=INNODB; INSERT INTO t1 VALUES('a'), ('cccc'), ('až'), ('cčc'), ('ggᵷg'), ('¢¢'); INSERT INTO t1 VALUES('தமிழ்'), ('🐱🌑'), ('🌒'), ('🌑'); INSERT INTO t1 VALUES('😊me'), ('eu€'), ('ls¢'); --echo # Eligible - record length is shorter than prefix let $base_count = query_get_value($show_count_statement, Value, 1); let $base_opt = query_get_value($show_opt_statement, Value, 1); SELECT f1 FROM t1 FORCE INDEX (`f1`) WHERE f1 = 'a'; let $count = query_get_value($show_count_statement, Value, 1); let $opt = query_get_value($show_opt_statement, Value, 1); --disable_query_log eval set @cluster_lookups = $count - $base_count; eval set @cluster_lookups_avoided = $opt - $base_opt; --enable_query_log select @cluster_lookups; select @cluster_lookups_avoided; --echo # Not eligible - record length longer than prefix length let $base_count = query_get_value($show_count_statement, Value, 1); let $base_opt = query_get_value($show_opt_statement, Value, 1); SELECT f1 FROM t1 FORCE INDEX (`f1`) WHERE f1 like 'c%'; let $count = query_get_value($show_count_statement, Value, 1); let $opt = query_get_value($show_opt_statement, Value, 1); --disable_query_log eval set @cluster_lookups = $count - $base_count; eval set @cluster_lookups_avoided = $opt - $base_opt; --enable_query_log select @cluster_lookups; select @cluster_lookups_avoided; --echo # Eligible - record length shorter than prefix length let $base_count = query_get_value($show_count_statement, Value, 1); let $base_opt = query_get_value($show_opt_statement, Value, 1); SELECT f1 FROM t1 FORCE INDEX (`f1`) WHERE f1 = 'až'; let $count = query_get_value($show_count_statement, Value, 1); let $opt = query_get_value($show_opt_statement, Value, 1); --disable_query_log eval set @cluster_lookups = $count - $base_count; eval set @cluster_lookups_avoided = $opt - $base_opt; --enable_query_log select @cluster_lookups; select @cluster_lookups_avoided; --echo # Not eligible - record length longer than prefix length let $base_count = query_get_value($show_count_statement, Value, 1); let $base_opt = query_get_value($show_opt_statement, Value, 1); SELECT f1 FROM t1 FORCE INDEX (`f1`) WHERE f1 = 'தமிழ்'; let $count = query_get_value($show_count_statement, Value, 1); let $opt = query_get_value($show_opt_statement, Value, 1); --disable_query_log eval set @cluster_lookups = $count - $base_count; eval set @cluster_lookups_avoided = $opt - $base_opt; --enable_query_log select @cluster_lookups; select @cluster_lookups_avoided; --echo # Not eligible - record length longer than prefix length let $base_count = query_get_value($show_count_statement, Value, 1); let $base_opt = query_get_value($show_opt_statement, Value, 1); SELECT f1 FROM t1 FORCE INDEX (`f1`) WHERE f1 like 'ggᵷ%'; let $count = query_get_value($show_count_statement, Value, 1); let $opt = query_get_value($show_opt_statement, Value, 1); --disable_query_log eval set @cluster_lookups = $count - $base_count; eval set @cluster_lookups_avoided = $opt - $base_opt; --enable_query_log select @cluster_lookups; select @cluster_lookups_avoided; --echo # Not eligible - record length longer than prefix length let $base_count = query_get_value($show_count_statement, Value, 1); let $base_opt = query_get_value($show_opt_statement, Value, 1); SELECT f1 FROM t1 FORCE INDEX (`f1`) WHERE f1 like '😊%'; let $count = query_get_value($show_count_statement, Value, 1); let $opt = query_get_value($show_opt_statement, Value, 1); --disable_query_log eval set @cluster_lookups = $count - $base_count; eval set @cluster_lookups_avoided = $opt - $base_opt; --enable_query_log select @cluster_lookups; select @cluster_lookups_avoided; --echo # Not eligible - record length longer than prefix length let $base_count = query_get_value($show_count_statement, Value, 1); let $base_opt = query_get_value($show_opt_statement, Value, 1); SELECT f1 FROM t1 FORCE INDEX (`f1`) WHERE f1 = 'ls¢'; let $count = query_get_value($show_count_statement, Value, 1); let $opt = query_get_value($show_opt_statement, Value, 1); --disable_query_log eval set @cluster_lookups = $count - $base_count; eval set @cluster_lookups_avoided = $opt - $base_opt; --enable_query_log select @cluster_lookups; select @cluster_lookups_avoided; --echo # Eligible - record length shorter than prefix length let $base_count = query_get_value($show_count_statement, Value, 1); let $base_opt = query_get_value($show_opt_statement, Value, 1); SELECT f1 FROM t1 FORCE INDEX(`f1`) WHERE f1 like '¢¢%'; let $count = query_get_value($show_count_statement, Value, 1); let $opt = query_get_value($show_opt_statement, Value, 1); --disable_query_log eval set @cluster_lookups = $count - $base_count; eval set @cluster_lookups_avoided = $opt - $base_opt; --enable_query_log select @cluster_lookups; select @cluster_lookups_avoided; --echo # Eligible - record length shorter than prefix length let $base_count = query_get_value($show_count_statement, Value, 1); let $base_opt = query_get_value($show_opt_statement, Value, 1); SELECT f1 FROM t1 FORCE INDEX (`f1`) WHERE f1 like '🐱🌑%'; let $count = query_get_value($show_count_statement, Value, 1); let $opt = query_get_value($show_opt_statement, Value, 1); --disable_query_log eval set @cluster_lookups = $count - $base_count; eval set @cluster_lookups_avoided = $opt - $base_opt; --enable_query_log select @cluster_lookups; select @cluster_lookups_avoided; --echo # Eligible - record length is shorter than prefix length let $base_count = query_get_value($show_count_statement, Value, 1); let $base_opt = query_get_value($show_opt_statement, Value, 1); SELECT f1 FROM t1 FORCE INDEX (`f1`) WHERE f1 like '🌑%'; let $count = query_get_value($show_count_statement, Value, 1); let $opt = query_get_value($show_opt_statement, Value, 1); --disable_query_log eval set @cluster_lookups = $count - $base_count; eval set @cluster_lookups_avoided = $opt - $base_opt; --enable_query_log select @cluster_lookups; select @cluster_lookups_avoided; --echo # Eligible - record length is shorter than prefix length let $base_count = query_get_value($show_count_statement, Value, 1); let $base_opt = query_get_value($show_opt_statement, Value, 1); SELECT f1 FROM t1 FORCE INDEX (`f1`) WHERE f1 like '🌒%'; let $count = query_get_value($show_count_statement, Value, 1); let $opt = query_get_value($show_opt_statement, Value, 1); --disable_query_log eval set @cluster_lookups = $count - $base_count; eval set @cluster_lookups_avoided = $opt - $base_opt; --enable_query_log select @cluster_lookups; select @cluster_lookups_avoided; DROP TABLE t1; CREATE TABLE t1( col1 INT, col2 BLOB DEFAULT NULL, INDEX `idx1`(col2(4), col1))ENGINE=INNODB; INSERT INTO t1 VALUES (2, 'test'), (3, repeat('test1', 2000)); INSERT INTO t1(col1) VALUES(1); --echo # Eligible - record length is shorter than prefix length let $base_count = query_get_value($show_count_statement, Value, 1); let $base_opt = query_get_value($show_opt_statement, Value, 1); SELECT col1 FROM t1 FORCE INDEX (`idx1`) WHERE col2 is NULL; let $count = query_get_value($show_count_statement, Value, 1); let $opt = query_get_value($show_opt_statement, Value, 1); --disable_query_log eval set @cluster_lookups = $count - $base_count; eval set @cluster_lookups_avoided = $opt - $base_opt; --enable_query_log select @cluster_lookups; select @cluster_lookups_avoided; --echo # Not eligible - record length longer than prefix index let $base_count = query_get_value($show_count_statement, Value, 1); let $base_opt = query_get_value($show_opt_statement, Value, 1); SELECT col1 FROM t1 FORCE INDEX (`idx1`) WHERE col2 like 'test1%'; let $count = query_get_value($show_count_statement, Value, 1); let $opt = query_get_value($show_opt_statement, Value, 1); --disable_query_log eval set @cluster_lookups = $count - $base_count; eval set @cluster_lookups_avoided = $opt - $base_opt; --enable_query_log select @cluster_lookups; select @cluster_lookups_avoided; DROP TABLE t1; set global innodb_prefix_index_cluster_optimization = OFF;