mirror of
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b3c74bdc1f
MDEV-28073 Slow query performance in MariaDB when using many tables The faster we can find a good query plan, the more options we have for finding and pruning (ignoring) bad plans. This patch adds sorting of plans to best_extension_by_limited_search(). The plans, from best_access_path() are sorted according to the numbers of found rows. This allows us to faster find 'good tables' and we are thus able to eliminate 'bad plans' faster. One side effect of this patch is that if two tables have equal cost, the table that which was used earlier in the query is preferred. This allows users to improve plans by reordering eq_ref tables in the order they would like them to be uses. Result changes caused by the patch: - Traces are different as now we print the cost for using tables before we start considering them in the plan. - Table order are changed for some plans. In most cases this is because the plans are equal and tables are in this case sorted according to their usage in the original query. - A few plans was changed as the optimizer was able to find a better plan (that was pruned by the original code). Other things: - Added a new statistic variable: "optimizer_join_prefixes_check_calls", which counts number of calls to best_extension_by_limited_search(). This can be used to check the prune efficiency in greedy_search(). - Added variable "JOIN_TAB::embedded_dependent" to be able to handle XX IN (SELECT..) in the greedy_optimizer. The idea is that we should prune a table if any of the tables in embedded_dependent is not yet read. - When using many tables in a query, there will be some additional memory usage as we need to pre-allocate table of table_count*table_count*sizeof(POSITION) objects (POSITION is 312 bytes for now) to hold the pre-calculated best_access_path() information. This memory usage is offset by the expected performance improvement when using many tables in a query. - Removed the code from an earlier patch to keep the table order in join->best_ref in the original order. This is not needed anymore as we are now sorting the tables for each best_extension_by_limited_search() call.
838 lines
31 KiB
Text
838 lines
31 KiB
Text
SET SESSION DEFAULT_STORAGE_ENGINE='InnoDB';
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set @innodb_stats_persistent_save= @@innodb_stats_persistent;
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set @innodb_stats_persistent_sample_pages_save=
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@@innodb_stats_persistent_sample_pages;
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set global innodb_stats_persistent= 1;
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set global innodb_stats_persistent_sample_pages=100;
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CREATE DATABASE dbt3_s001;
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use dbt3_s001;
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explain
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select count(*) from lineitem where l_orderkey=130 and l_shipdate='1992-07-01';
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE lineitem ref PRIMARY,i_l_shipdate,i_l_orderkey,i_l_orderkey_quantity i_l_shipdate 8 const,const 1 Using index
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flush status;
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select count(*) from lineitem where l_orderkey=130 and l_shipdate='1992-07-01';
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count(*)
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1
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show status like 'handler_read%';
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Variable_name Value
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Handler_read_first 0
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Handler_read_key 1
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Handler_read_last 0
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Handler_read_next 1
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Handler_read_prev 0
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Handler_read_retry 0
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Handler_read_rnd 0
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Handler_read_rnd_deleted 0
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Handler_read_rnd_next 0
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explain
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select count(*) from lineitem use index(primary)
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where l_orderkey=130 and l_linenumber=2 and l_shipdate='1992-07-01';
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE lineitem const PRIMARY PRIMARY 8 const,const 1
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flush status;
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select count(*) from lineitem use index(primary)
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where l_orderkey=130 and l_linenumber=2 and l_shipdate='1992-07-01';
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count(*)
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1
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show status like 'handler_read%';
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Variable_name Value
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Handler_read_first 0
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Handler_read_key 1
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Handler_read_last 0
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Handler_read_next 0
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Handler_read_prev 0
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Handler_read_retry 0
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Handler_read_rnd 0
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Handler_read_rnd_deleted 0
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Handler_read_rnd_next 0
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explain
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select count(*) from lineitem
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where l_shipdate='1992-07-01' and l_orderkey between 1 and 1000;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE lineitem range PRIMARY,i_l_shipdate,i_l_orderkey,i_l_orderkey_quantity i_l_shipdate 8 NULL 1 Using where; Using index
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flush status;
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select count(*) from lineitem
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where l_shipdate='1992-07-01' and l_orderkey between 1 and 1000;
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count(*)
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1
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show status like 'handler_read%';
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Variable_name Value
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Handler_read_first 0
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Handler_read_key 1
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Handler_read_last 0
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Handler_read_next 1
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Handler_read_prev 0
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Handler_read_retry 0
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Handler_read_rnd 0
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Handler_read_rnd_deleted 0
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Handler_read_rnd_next 0
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explain
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select l_orderkey, l_linenumber from lineitem
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where l_shipdate='1992-07-01' and l_orderkey between 1001 and 2000;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE lineitem range PRIMARY,i_l_shipdate,i_l_orderkey,i_l_orderkey_quantity i_l_shipdate 8 NULL 3 Using where; Using index
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flush status;
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select l_orderkey, l_linenumber from lineitem
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where l_shipdate='1992-07-01' and l_orderkey between 1001 and 2000;
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l_orderkey l_linenumber
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1088 3
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1217 1
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1221 3
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show status like 'handler_read%';
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Variable_name Value
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Handler_read_first 0
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Handler_read_key 1
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Handler_read_last 0
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Handler_read_next 3
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Handler_read_prev 0
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Handler_read_retry 0
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Handler_read_rnd 0
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Handler_read_rnd_deleted 0
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Handler_read_rnd_next 0
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explain
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select min(l_orderkey) from lineitem where l_shipdate='1992-07-01';
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE NULL NULL NULL NULL NULL NULL NULL Select tables optimized away
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flush status;
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select min(l_orderkey) from lineitem where l_shipdate='1992-07-01';
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min(l_orderkey)
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130
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show status like 'handler_read%';
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Variable_name Value
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Handler_read_first 0
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Handler_read_key 1
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Handler_read_last 0
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Handler_read_next 0
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Handler_read_prev 0
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Handler_read_retry 0
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Handler_read_rnd 0
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Handler_read_rnd_deleted 0
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Handler_read_rnd_next 0
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explain
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select min(l_orderkey) from lineitem
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where l_shipdate='1992-07-01' and l_orderkey between 1001 and 2000;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE NULL NULL NULL NULL NULL NULL NULL Select tables optimized away
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flush status;
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select min(l_orderkey) from lineitem
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where l_shipdate='1992-07-01' and l_orderkey between 1001 and 2000;
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min(l_orderkey)
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1088
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show status like 'handler_read%';
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Variable_name Value
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Handler_read_first 0
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Handler_read_key 1
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Handler_read_last 0
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Handler_read_next 0
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Handler_read_prev 0
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Handler_read_retry 0
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Handler_read_rnd 0
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Handler_read_rnd_deleted 0
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Handler_read_rnd_next 0
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explain
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select max(l_linenumber) from lineitem
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where l_shipdate='1992-07-01' and l_orderkey=130;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE NULL NULL NULL NULL NULL NULL NULL Select tables optimized away
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flush status;
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select max(l_linenumber) from lineitem
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where l_shipdate='1992-07-01' and l_orderkey=130;
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max(l_linenumber)
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2
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show status like 'handler_read%';
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Variable_name Value
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Handler_read_first 0
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Handler_read_key 1
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Handler_read_last 0
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Handler_read_next 0
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Handler_read_prev 0
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Handler_read_retry 0
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Handler_read_rnd 0
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Handler_read_rnd_deleted 0
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Handler_read_rnd_next 0
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explain
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select l_orderkey, l_linenumber
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from lineitem use index (i_l_shipdate, i_l_receiptdate)
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where l_shipdate='1992-07-01' and l_orderkey=130
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or l_receiptdate='1992-07-01' and l_orderkey=5603;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE lineitem index_merge i_l_shipdate,i_l_receiptdate i_l_shipdate,i_l_receiptdate 8,8 NULL 2 Using union(i_l_shipdate,i_l_receiptdate); Using where
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flush status;
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select l_orderkey, l_linenumber
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from lineitem use index (i_l_shipdate, i_l_receiptdate)
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where l_shipdate='1992-07-01' and l_orderkey=130
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or l_receiptdate='1992-07-01' and l_orderkey=5603;
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l_orderkey l_linenumber
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130 2
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5603 2
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show status like 'handler_read%';
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Variable_name Value
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Handler_read_first 0
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Handler_read_key 2
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Handler_read_last 0
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Handler_read_next 2
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Handler_read_prev 0
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Handler_read_retry 0
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Handler_read_rnd 2
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Handler_read_rnd_deleted 0
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Handler_read_rnd_next 0
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explain
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select l_orderkey, l_linenumber
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from lineitem use index (i_l_shipdate, i_l_receiptdate)
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where l_shipdate='1992-07-01' and l_orderkey between 1 and 1000
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or l_receiptdate='1992-07-01' and l_orderkey between 5001 and 6000;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE lineitem index_merge i_l_shipdate,i_l_receiptdate i_l_shipdate,i_l_receiptdate # NULL 3 Using sort_union(i_l_shipdate,i_l_receiptdate); Using where
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flush status;
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select l_orderkey, l_linenumber
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from lineitem use index (i_l_shipdate, i_l_receiptdate)
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where l_shipdate='1992-07-01' and l_orderkey between 1 and 1000
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or l_receiptdate='1992-07-01' and l_orderkey between 5001 and 6000;
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l_orderkey l_linenumber
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130 2
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5603 2
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5959 3
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show status like 'handler_read%';
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Variable_name Value
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Handler_read_first 0
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Handler_read_key 2
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Handler_read_last 0
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Handler_read_next 3
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Handler_read_prev 0
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Handler_read_retry 0
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Handler_read_rnd 3
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Handler_read_rnd_deleted 0
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Handler_read_rnd_next 0
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explain
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select l_orderkey, l_linenumber from lineitem
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where l_shipdate='1992-07-01' and l_orderkey between 1 and 1000
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or l_receiptdate='1992-07-01' and l_orderkey between 5001 and 6000;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE lineitem index_merge PRIMARY,i_l_shipdate,i_l_receiptdate,i_l_orderkey,i_l_orderkey_quantity i_l_shipdate,i_l_receiptdate # NULL # Using
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flush status;
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select l_orderkey, l_linenumber from lineitem
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where l_shipdate='1992-07-01' and l_orderkey between 1 and 1000
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or l_receiptdate='1992-07-01' and l_orderkey between 5001 and 6000;
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l_orderkey l_linenumber
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130 2
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5603 2
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5959 3
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show status like 'handler_read_next';
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Variable_name Value
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Handler_read_next 3
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explain
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select max(l_orderkey) from lineitem
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where l_partkey between 1 and 10 group by l_partkey;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE lineitem range i_l_suppkey_partkey,i_l_partkey i_l_partkey 5 NULL # Using where; Using index for group-by
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flush status;
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select max(l_orderkey) from lineitem
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where l_partkey between 1 and 10 group by l_partkey;
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max(l_orderkey)
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5984
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5957
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5892
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5856
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5959
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5957
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5794
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5894
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5859
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5632
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show status like 'handler_read%';
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Variable_name Value
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Handler_read_first 0
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Handler_read_key 21
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Handler_read_last 1
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Handler_read_next 0
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Handler_read_prev 0
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Handler_read_retry 0
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Handler_read_rnd 0
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Handler_read_rnd_deleted 0
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Handler_read_rnd_next 0
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explain
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select max(l_orderkey) from lineitem
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where l_suppkey in (1,4) group by l_suppkey;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE lineitem range i_l_suppkey i_l_suppkey 5 NULL # Using where; Using index for group-by
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flush status;
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select max(l_orderkey) from lineitem
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where l_suppkey in (1,4) group by l_suppkey;
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max(l_orderkey)
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5988
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5984
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show status like 'handler_read%';
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Variable_name Value
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Handler_read_first 0
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Handler_read_key 6
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Handler_read_last 1
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Handler_read_next 0
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Handler_read_prev 0
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Handler_read_retry 0
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Handler_read_rnd 0
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Handler_read_rnd_deleted 0
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Handler_read_rnd_next 0
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create index i_p_retailprice on part(p_retailprice);
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explain
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select o_orderkey, p_partkey
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from part use index (i_p_retailprice),
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lineitem use index (i_l_partkey), orders
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where p_retailprice > 1100 and o_orderdate='1997-01-01'
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and o_orderkey=l_orderkey and p_partkey=l_partkey;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE part range i_p_retailprice i_p_retailprice 9 NULL # Using where; Using index
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1 SIMPLE orders ref PRIMARY,i_o_orderdate i_o_orderdate 4 const # Using index
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1 SIMPLE lineitem ref i_l_partkey i_l_partkey 9 dbt3_s001.part.p_partkey,dbt3_s001.orders.o_orderkey # Using index
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flush status;
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select o_orderkey, p_partkey
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from part use index (i_p_retailprice),
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lineitem use index (i_l_partkey), orders
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where p_retailprice > 1100 and o_orderdate='1997-01-01'
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and o_orderkey=l_orderkey and p_partkey=l_partkey;
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o_orderkey p_partkey
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5895 200
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show status like 'handler_read%';
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Variable_name Value
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Handler_read_first 0
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Handler_read_key 3
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Handler_read_last 0
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Handler_read_next 3
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Handler_read_prev 0
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Handler_read_retry 0
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Handler_read_rnd 0
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Handler_read_rnd_deleted 0
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Handler_read_rnd_next 0
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#
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# Bug mdev-3851: ref access used instead of expected eq_ref access
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# when extended_keys=on
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#
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create table t0 (a int);
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insert into t0 values (1), (2), (3), (4), (5);
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create index i_p_size on part(p_size);
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explain
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select * from t0, part ignore index (primary)
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where p_partkey=t0.a and p_size=1;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t0 ALL NULL NULL NULL NULL 5 Using where
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1 SIMPLE part eq_ref i_p_size i_p_size 9 const,dbt3_s001.t0.a 1
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select * from t0, part ignore index (primary)
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where p_partkey=t0.a and p_size=1;
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a p_partkey p_name p_mfgr p_brand p_type p_size p_container p_retailprice p_comment
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2 2 blush rosy metallic lemon navajo Manufacturer#1 Brand#13 LARGE BRUSHED BRASS 1 LG CASE 902 final platelets hang f
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drop table t0;
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drop index i_p_size on part;
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DROP DATABASE dbt3_s001;
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use test;
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#
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# LP Bug #914560: query containing IN subquery
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# + extended_keys = on
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#
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set @save_optimizer_switch=@@optimizer_switch;
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SET optimizer_switch='materialization=on,semijoin=on';
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CREATE TABLE t1 (a int, b int) ENGINE=MyISAM;
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INSERT INTO t1 VALUES (1,1), (2,2);
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SELECT * FROM t1 WHERE 2 IN (SELECT MAX(s1.a) FROM t1 AS s1, t1 AS s2);
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a b
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1 1
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2 2
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EXPLAIN
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SELECT * FROM t1 WHERE 2 IN (SELECT MAX(s1.a) FROM t1 AS s1, t1 AS s2);
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id select_type table type possible_keys key key_len ref rows Extra
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1 PRIMARY <subquery2> const distinct_key distinct_key 4 const 1
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1 PRIMARY t1 ALL NULL NULL NULL NULL 2 Using join buffer (flat, BNL join)
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2 MATERIALIZED s1 ALL NULL NULL NULL NULL 2
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2 MATERIALIZED s2 ALL NULL NULL NULL NULL 2 Using join buffer (flat, BNL join)
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DROP TABLE t1;
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set optimizer_switch=@save_optimizer_switch;
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#
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# LP Bug #915291: query using a materialized view
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# + extended_keys = on
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# (valgrinf complains fixed by the patch for bug #914560)
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#
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SET optimizer_switch = 'derived_with_keys=on';
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CREATE TABLE t1 (a varchar(1)) ENGINE=MyISAM;
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INSERT INTO t1 VALUES ('j'), ('v');
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CREATE TABLE t2 (b varchar(1)) ENGINE=MyISAM;
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INSERT INTO t2 VALUES ('j'), ('v');
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CREATE TABLE t3 (c varchar(1));
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INSERT INTO t2 VALUES ('m'), ('n');
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CREATE VIEW v
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AS SELECT DISTINCT * FROM t2 STRAIGHT_JOIN t3;
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SELECT * FROM t1, v WHERE a = b;
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a b c
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DROP VIEW v;
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DROP TABLE t1,t2,t3;
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set optimizer_switch=@save_optimizer_switch;
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#
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# LP Bug #921167: query containing IN subquery
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# + extended_keys = on
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#
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CREATE TABLE t1 (
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a int NOT NULL, b varchar(1) NOT NULL, KEY(a), KEY(b,a)
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) ENGINE=MyISAM;
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INSERT INTO t1 VALUES
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(0,'j'), (8,'v'), (1,'c'), (8,'m'), (9,'d'),
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(24,'d'), (6,'y'), (1,'t'), (6,'d'), (2,'s');
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CREATE TABLE t2 (
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c int NOT NULL PRIMARY KEY
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) ENGINE=MyISAM;
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INSERT INTO t2 VALUES
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(10), (11), (12), (13), (14),
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(15), (16), (17), (18), (19), (24);
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EXPLAIN
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SELECT a FROM t1 AS t, t2
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WHERE c = a AND b IN (SELECT b FROM t1, t2 WHERE b = t.b);
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id select_type table type possible_keys key key_len ref rows Extra
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1 PRIMARY t index a,b b 7 NULL 10 Using index
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1 PRIMARY t2 eq_ref PRIMARY PRIMARY 4 test.t.a 1 Using index
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1 PRIMARY t1 ref b b 3 test.t.b 2 Using index; Start temporary
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1 PRIMARY t2 index NULL PRIMARY 4 NULL 11 Using index; End temporary; Using join buffer (flat, BNL join)
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SELECT a FROM t1 AS t, t2
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WHERE c = a AND b IN (SELECT b FROM t1, t2 WHERE b = t.b);
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a
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24
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DROP TABLE t1,t2;
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#
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# LP Bug #923236: hash join + extended_keys = on
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#
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CREATE TABLE t1 (a int) ENGINE=MyISAM;
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CREATE TABLE t2 (b int) ENGINE=MyISAM;
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INSERT INTO t1 (a) VALUES (4), (6);
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INSERT INTO t2 (b) VALUES (0), (8);
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set @save_join_cache_level=@@join_cache_level;
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SET join_cache_level=3;
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SET optimizer_switch='join_cache_hashed=on';
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SET optimizer_switch='join_cache_bka=on';
|
|
EXPLAIN
|
|
SELECT * FROM t1, t2 WHERE b=a;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 ALL NULL NULL NULL NULL 2 Using where
|
|
1 SIMPLE t2 hash_ALL NULL #hash#$hj 5 test.t1.a 2 Using where; Using join buffer (flat, BNLH join)
|
|
SELECT * FROM t1, t2 WHERE b=a;
|
|
a b
|
|
set join_cache_level=@save_join_cache_level;
|
|
set optimizer_switch=@save_optimizer_switch;
|
|
DROP TABLE t1,t2;
|
|
#
|
|
# Bug mdev-3888: INSERT with UPDATE on duplicate keys
|
|
# with extended_keys=on
|
|
#
|
|
CREATE TABLE t1 (
|
|
c1 bigint(20) unsigned NOT NULL AUTO_INCREMENT,
|
|
c2 bigint(20) unsigned NOT NULL,
|
|
c3 bigint(20) unsigned NOT NULL,
|
|
c4 varchar(128) DEFAULT NULL,
|
|
PRIMARY KEY (c1),
|
|
UNIQUE KEY uq (c2,c3),
|
|
KEY c3 (c3),
|
|
KEY c4 (c4)
|
|
) ENGINE=InnoDB AUTO_INCREMENT=5 DEFAULT CHARSET=utf8;
|
|
INSERT INTO t1 (c2, c3, c4) VALUES (58291525, 2580, 'foobar')
|
|
ON DUPLICATE KEY UPDATE c4 = VALUES(c4);
|
|
INSERT INTO t1 (c2, c3, c4) VALUES (58291525, 2580, 'foobar')
|
|
ON DUPLICATE KEY UPDATE c4 = VALUES(c4);
|
|
DROP TABLE t1;
|
|
#
|
|
# Bug mdev-4220: using ref instead of eq_ref
|
|
# with extended_keys=on
|
|
# (performance regression introduced in the patch for mdev-3851)
|
|
#
|
|
create table t1 (a int not null) engine=innodb;
|
|
insert into t1 values (0),(1),(2),(3),(4),(5),(6),(7),(8),(9);
|
|
create table t2 (
|
|
pk int primary key, a int not null, b int, unique(a)
|
|
)engine=innodb;
|
|
insert into t2
|
|
select
|
|
A.a + 10 * B.a, A.a + 10 * B.a, A.a + 10 * B.a
|
|
from t1 A, t1 B;
|
|
explain
|
|
select * from t1, t2 where t2.a=t1.a and t2.b < 2;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 ALL NULL NULL NULL NULL #
|
|
1 SIMPLE t2 eq_ref a a 4 test.t1.a # Using where
|
|
flush status;
|
|
select * from t1, t2 where t2.a=t1.a and t2.b < 2;
|
|
a pk a b
|
|
0 0 0 0
|
|
1 1 1 1
|
|
show status like 'handler_read%';
|
|
Variable_name Value
|
|
Handler_read_first 0
|
|
Handler_read_key 10
|
|
Handler_read_last 0
|
|
Handler_read_next 0
|
|
Handler_read_prev 0
|
|
Handler_read_retry 0
|
|
Handler_read_rnd 0
|
|
Handler_read_rnd_deleted 0
|
|
Handler_read_rnd_next 11
|
|
drop table t1,t2;
|
|
create table t1(a int) engine=myisam;
|
|
insert into t1 values (0),(1),(2),(3),(4),(5),(6),(7),(8),(9);
|
|
create table t2(a int) engine=myisam;
|
|
insert into t2 select A.a + 10*B.a + 100*C.a from t1 A, t1 B, t1 C;
|
|
create table t3 (
|
|
pk1 int not null, pk2 int not null, col1 int not null, col2 int not null)
|
|
engine=innodb;
|
|
insert into t3 select a,a,a,a from t2;
|
|
alter table t3 add primary key (pk1, pk2);
|
|
alter table t3 add key (col1, col2);
|
|
analyze table t1,t3;
|
|
Table Op Msg_type Msg_text
|
|
test.t1 analyze status Engine-independent statistics collected
|
|
test.t1 analyze status OK
|
|
test.t3 analyze status Engine-independent statistics collected
|
|
test.t3 analyze status OK
|
|
explain
|
|
select * from t1, t3 where t3.col1=t1.a and t3.col2=t1.a;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 ALL NULL NULL NULL NULL # Using where
|
|
1 SIMPLE t3 ref col1 col1 8 test.t1.a,test.t1.a # Using index
|
|
explain
|
|
select * from t1, t3 where t3.col1=t1.a and t3.col2=t1.a and t3.pk1=t1.a;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 ALL NULL NULL NULL NULL # Using where
|
|
1 SIMPLE t3 ref PRIMARY,col1 col1 12 test.t1.a,test.t1.a,test.t1.a # Using index
|
|
drop table t1,t2,t3;
|
|
#
|
|
# Bug mdev-4340: performance regression with extended_keys=on
|
|
#
|
|
CREATE TABLE t1 (
|
|
page_id int(8) unsigned NOT NULL AUTO_INCREMENT,
|
|
page_namespace int(11) NOT NULL DEFAULT '0',
|
|
page_title varbinary(255) NOT NULL DEFAULT '',
|
|
page_restrictions tinyblob NOT NULL,
|
|
page_counter bigint(20) unsigned NOT NULL DEFAULT '0',
|
|
page_is_redirect tinyint(1) unsigned NOT NULL DEFAULT '0',
|
|
page_is_new tinyint(1) unsigned NOT NULL DEFAULT '0',
|
|
page_random double unsigned NOT NULL DEFAULT '0',
|
|
page_touched varbinary(14) NOT NULL DEFAULT '',
|
|
page_latest int(8) unsigned NOT NULL DEFAULT '0',
|
|
page_len int(8) unsigned NOT NULL DEFAULT '0',
|
|
PRIMARY KEY (page_id),
|
|
UNIQUE KEY name_title (page_namespace,page_title),
|
|
KEY page_random (page_random),
|
|
KEY page_len (page_len),
|
|
KEY page_redirect_namespace_len (page_is_redirect,page_namespace,page_len)
|
|
) ENGINE=InnoDB AUTO_INCREMENT=38929100 DEFAULT CHARSET=binary;
|
|
INSERT INTO t1 VALUES
|
|
(38928077,0,'Sandbox','',0,0,0,0,'',0,0),(38928078,1,'Sandbox','',0,0,0,1,'',0,0),
|
|
(38928079,2,'Sandbox','',0,0,0,2,'',0,0),(38928080,3,'Sandbox','',0,0,0,3,'',0,0),
|
|
(38928081,4,'Sandbox','',0,0,0,4,'',0,0),(38928082,5,'Sandbox','',0,0,0,5,'',0,0);
|
|
CREATE TABLE t2 (
|
|
rev_id int(8) unsigned NOT NULL AUTO_INCREMENT,
|
|
rev_page int(8) unsigned NOT NULL DEFAULT '0',
|
|
rev_text_id int(8) unsigned NOT NULL DEFAULT '0',
|
|
rev_comment varbinary(255) DEFAULT NULL,
|
|
rev_user int(5) unsigned NOT NULL DEFAULT '0',
|
|
rev_user_text varbinary(255) NOT NULL DEFAULT '',
|
|
rev_timestamp varbinary(14) NOT NULL DEFAULT '',
|
|
rev_minor_edit tinyint(1) unsigned NOT NULL DEFAULT '0',
|
|
rev_deleted tinyint(1) unsigned NOT NULL DEFAULT '0',
|
|
rev_len int(8) unsigned DEFAULT NULL,
|
|
rev_parent_id int(8) unsigned DEFAULT NULL,
|
|
rev_sha1 varbinary(32) NOT NULL DEFAULT '',
|
|
PRIMARY KEY (rev_page,rev_id),
|
|
UNIQUE KEY rev_id (rev_id),
|
|
KEY rev_timestamp (rev_timestamp),
|
|
KEY page_timestamp (rev_page,rev_timestamp),
|
|
KEY user_timestamp (rev_user,rev_timestamp),
|
|
KEY usertext_timestamp (rev_user_text,rev_timestamp,rev_user,rev_deleted,rev_minor_edit,rev_text_id,rev_comment)
|
|
) ENGINE=InnoDB DEFAULT CHARSET=binary;
|
|
INSERT INTO t2 VALUES
|
|
(547116222,20,0,NULL,3,'','',0,0,NULL,NULL,''),(547117245,20,0,NULL,4,'','',0,0,NULL,NULL,''),
|
|
(547118268,20,0,NULL,5,'','',0,0,NULL,NULL,''),(547114177,21,0,NULL,1,'','',0,0,NULL,NULL,''),
|
|
(547115200,21,0,NULL,2,'','',0,0,NULL,NULL,''),(547116223,21,0,NULL,3,'','',0,0,NULL,NULL,''),
|
|
(547117246,21,0,NULL,4,'','',0,0,NULL,NULL,''),(547118269,21,0,NULL,5,'','',0,0,NULL,NULL,''),
|
|
(547114178,22,0,NULL,1,'','',0,0,NULL,NULL,''),(547115201,22,0,NULL,2,'','',0,0,NULL,NULL,''),
|
|
(547116224,22,0,NULL,3,'','',0,0,NULL,NULL,''),(547117247,22,0,NULL,4,'','',0,0,NULL,NULL,''),
|
|
(547116226,24,0,NULL,3,'','',0,0,NULL,NULL,''),(547117249,24,0,NULL,4,'','',0,0,NULL,NULL,''),
|
|
(547118272,24,0,NULL,5,'','',0,0,NULL,NULL,''),(547114181,25,0,NULL,1,'','',0,0,NULL,NULL,''),
|
|
(547115204,25,0,NULL,2,'','',0,0,NULL,NULL,''),(547116227,25,0,NULL,3,'','',0,0,NULL,NULL,''),
|
|
(547116157,978,0,NULL,2,'','',0,0,NULL,NULL,''),(547117180,978,0,NULL,3,'','',0,0,NULL,NULL,''),
|
|
(547118203,978,0,NULL,4,'','',0,0,NULL,NULL,''),(547119226,978,0,NULL,5,'','',0,0,NULL,NULL,''),
|
|
(547115135,979,0,NULL,1,'','',0,0,NULL,NULL,''),(547116158,979,0,NULL,2,'','',0,0,NULL,NULL,''),
|
|
(547116173,994,0,NULL,2,'','',0,0,NULL,NULL,''),(547117196,994,0,NULL,3,'','',0,0,NULL,NULL,''),
|
|
(547118219,994,0,NULL,4,'','',0,0,NULL,NULL,''),(547119242,994,0,NULL,5,'','',0,0,NULL,NULL,''),
|
|
(547115151,995,0,NULL,1,'','',0,0,NULL,NULL,''),(547116174,995,0,NULL,2,'','',0,0,NULL,NULL,''),
|
|
(547117197,995,0,NULL,3,'','',0,0,NULL,NULL,''),(547118220,995,0,NULL,4,'','',0,0,NULL,NULL,''),
|
|
(547118223,998,0,NULL,4,'','',0,0,NULL,NULL,''),(547119246,998,0,NULL,5,'','',0,0,NULL,NULL,''),
|
|
(547115155,999,0,NULL,1,'','',0,0,NULL,NULL,''),(547116178,999,0,NULL,2,'','',0,0,NULL,NULL,''),
|
|
(547117201,999,0,NULL,3,'','',0,0,NULL,NULL,''),(547118224,999,0,NULL,4,'','',0,0,NULL,NULL,''),
|
|
(547117213,999,0,NULL,3,'','',0,0,NULL,NULL,''),(547117217,999,0,NULL,4,'','',0,0,NULL,NULL,''),
|
|
(547117214,999,0,NULL,3,'','',0,0,NULL,NULL,''),(547117218,999,0,NULL,4,'','',0,0,NULL,NULL,''),
|
|
(547117215,999,0,NULL,3,'','',0,0,NULL,NULL,''),(547117219,999,0,NULL,4,'','',0,0,NULL,NULL,''),
|
|
(547117216,999,0,NULL,3,'','',0,0,NULL,NULL,''),(547117220,999,0,NULL,4,'','',0,0,NULL,NULL,''),
|
|
(547119271,38928081,0,NULL,10,'','',0,0,NULL,NULL,''),(547119272,38928081,0,NULL,11,'','',0,0,NULL,NULL,''),
|
|
(547119273,38928081,0,NULL,12,'','',0,0,NULL,NULL,''),(547119274,38928081,0,NULL,13,'','',0,0,NULL,NULL,''),
|
|
(547119275,38928081,0,NULL,14,'','',0,0,NULL,NULL,''),(547119276,38928081,0,NULL,15,'','',0,0,NULL,NULL,''),
|
|
(547119277,38928081,0,NULL,16,'','',0,0,NULL,NULL,''),(547119278,38928081,0,NULL,17,'','',0,0,NULL,NULL,''),
|
|
(547119279,38928081,0,NULL,18,'','',0,0,NULL,NULL,''),(547119280,38928081,0,NULL,19,'','',0,0,NULL,NULL,'');
|
|
CREATE TABLE t3 (
|
|
old_id int(10) unsigned NOT NULL AUTO_INCREMENT,
|
|
old_text mediumblob NOT NULL,
|
|
old_flags tinyblob NOT NULL,
|
|
PRIMARY KEY (old_id)
|
|
) ENGINE=InnoDB DEFAULT CHARSET=latin1;
|
|
INSERT INTO t3 VALUES
|
|
(1,'text-0',''),(2,'text-1000',''),(3,'text-2000',''),(4,'text-3000',''),
|
|
(5,'text-4000',''),(6,'text-5000',''),(7,'text-6000',''),(8,'text-7000',''),
|
|
(9,'text-8000',''),(10,'text-9000',''),(11,'text-1',''),(12,'text-1001',''),
|
|
(13,'text-2001',''),(14,'text-3001',''),(15,'text-4001',''),(16,'text-5001',''),
|
|
(17,'text-6001',''),(18,'text-7001',''),(19,'text-8001',''),(20,'text-9001',''),
|
|
(21,'text-2',''),(22,'text-1002',''),(23,'text-2002',''),(24,'text-3002',''),
|
|
(25,'text-4002',''),(26,'text-5002',''),(27,'text-6002',''),(28,'text-7002',''),
|
|
(29,'text-8002',''),(30,'text-9002',''),(31,'text-3',''),(32,'text-1003',''),
|
|
(33,'text-2003',''),(34,'text-3003',''),(35,'text-4003',''),(36,'text-5003',''),
|
|
(37,'text-6003',''),(38,'text-7003',''),(39,'text-8003',''),(40,'text-9003',''),
|
|
(41,'text-4',''),(42,'text-1004',''),(43,'text-2004',''),(44,'text-3004',''),
|
|
(45,'text-4004',''),(46,'text-5004',''),(47,'text-6004',''),(48,'text-7004',''),
|
|
(49,'text-8004',''),(50,'text-9004',''),(51,'text-5',''),(52,'text-1005',''),
|
|
(53,'text-2005',''),(54,'text-3005',''),(55,'text-4005',''),(56,'text-5005',''),
|
|
(57,'text-6005',''),(58,'text-7005',''),(59,'text-8005',''),(60,'text-9005',''),
|
|
(61,'text-6',''),(62,'text-1006',''),(63,'text-2006',''),(64,'text-3006',''),
|
|
(65,'text-4006',''),(66,'text-5006',''),(67,'text-6006',''),(68,'text-7006',''),
|
|
(69,'text-8006',''),(70,'text-9006',''),(71,'text-7',''),(72,'text-1007',''),
|
|
(73,'text-2007',''),(74,'text-3007',''),(75,'text-4007',''),(76,'text-5007',''),
|
|
(77,'text-6007',''),(78,'text-7007',''),(79,'text-8007',''),(80,'text-9007',''),
|
|
(81,'text-8',''),(82,'text-1008',''),(83,'text-2008',''),(84,'text-3008',''),
|
|
(85,'text-4008',''),(86,'text-5008',''),(87,'text-6008',''),(88,'text-7008',''),
|
|
(89,'text-8008',''),(90,'text-9008',''),(91,'text-9',''),(92,'text-1009',''),
|
|
(93,'text-2009',''),(94,'text-3009',''),(95,'text-4009',''),(96,'text-5009',''),
|
|
(97,'text-6009',''),(98,'text-7009',''),(99,'text-8009',''),(100,'text-9009','');
|
|
ANALYZE TABLE t1,t2,t3;
|
|
Table Op Msg_type Msg_text
|
|
test.t1 analyze status Engine-independent statistics collected
|
|
test.t1 analyze Warning Engine-independent statistics are not collected for column 'page_restrictions'
|
|
test.t1 analyze status OK
|
|
test.t2 analyze status Engine-independent statistics collected
|
|
test.t2 analyze status OK
|
|
test.t3 analyze status Engine-independent statistics collected
|
|
test.t3 analyze Warning Engine-independent statistics are not collected for column 'old_text'
|
|
test.t3 analyze Warning Engine-independent statistics are not collected for column 'old_flags'
|
|
test.t3 analyze status OK
|
|
EXPLAIN
|
|
SELECT * FROM t1, t2 IGNORE INDEX (PRIMARY), t3
|
|
WHERE page_id=rev_page AND rev_text_id=old_id AND page_namespace=4 AND page_title='Sandbox'
|
|
ORDER BY rev_timestamp ASC LIMIT 10;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 const PRIMARY,name_title name_title 261 const,const 1
|
|
1 SIMPLE t2 ref page_timestamp page_timestamp 4 const 10 Using where
|
|
1 SIMPLE t3 eq_ref PRIMARY PRIMARY 4 test.t2.rev_text_id 1
|
|
DROP TABLE t1,t2,t3;
|
|
#
|
|
# MDEV-5424 SELECT using ORDER BY DESC and LIMIT produces unexpected
|
|
# results (InnoDB/XtraDB)
|
|
#
|
|
create table t1 (a bigint not null unique auto_increment, b varchar(10), primary key (a), key (b(2))) engine = myisam default character set utf8;
|
|
create table t2 (a bigint not null unique auto_increment, b varchar(10), primary key (a), key (b(2))) engine = innodb default character set utf8;
|
|
insert into t1 (b) values (null), (null), (null);
|
|
insert into t2 (b) values (null), (null), (null);
|
|
analyze table t1,t2;
|
|
Table Op Msg_type Msg_text
|
|
test.t1 analyze status Engine-independent statistics collected
|
|
test.t1 analyze status OK
|
|
test.t2 analyze status Engine-independent statistics collected
|
|
test.t2 analyze status OK
|
|
explain select a from t1 where b is null order by a desc limit 2;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 index b PRIMARY 8 NULL 2 Using where
|
|
select a from t1 where b is null order by a desc limit 2;
|
|
a
|
|
3
|
|
2
|
|
explain select a from t2 where b is null order by a desc limit 2;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t2 range b b 9 NULL 3 Using where; Using filesort
|
|
select a from t2 where b is null order by a desc limit 2;
|
|
a
|
|
3
|
|
2
|
|
explain select a from t2 where b is null order by a desc;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t2 index b PRIMARY 8 NULL 3 Using where
|
|
select a from t2 where b is null order by a desc;
|
|
a
|
|
3
|
|
2
|
|
1
|
|
explain select a from t2 where b is null order by a desc,a,a;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t2 index b PRIMARY 8 NULL 3 Using where
|
|
select a from t2 where b is null order by a desc,a,a;
|
|
a
|
|
3
|
|
2
|
|
1
|
|
drop table t1, t2;
|
|
#
|
|
# MDEV-10325: Queries examines all rows of a tables when it should not
|
|
#
|
|
create table t0 (a int);
|
|
insert into t0 values (0),(1),(2),(3),(4),(5),(6),(7),(8),(9);
|
|
create table t1 (
|
|
pk int not null,
|
|
col1 varchar(32),
|
|
filler varchar(100),
|
|
key idx1(col1(10)),
|
|
primary key (pk)
|
|
)engine=innodb;
|
|
insert into t1
|
|
select
|
|
A.a + 10*B.a + 100*C.a,
|
|
concat('1234567890-', 1000+ A.a + 10*B.a + 100*C.a),
|
|
repeat('filler-data-', 4)
|
|
from
|
|
t0 A, t0 B, t0 C;
|
|
drop table t0,t1;
|
|
#
|
|
#
|
|
# MDEV-10360: Extended keys: index properties depend on index order
|
|
#
|
|
create table t0 (a int);
|
|
insert into t0 values (0),(1),(2),(3),(4),(5),(6),(7),(8),(9);
|
|
create table t1 (
|
|
index_id bigint(20) unsigned NOT NULL,
|
|
index_class varchar(265) COLLATE latin1_general_ci DEFAULT NULL ,
|
|
index_object_id int(10) unsigned NOT NULL DEFAULT '0' ,
|
|
index_date_updated int(10) unsigned DEFAULT NULL ,
|
|
PRIMARY KEY (index_id),
|
|
KEY object (index_class(181),index_object_id),
|
|
KEY index_date_updated (index_date_updated)
|
|
) engine=innodb;
|
|
create table t2 (
|
|
index_id bigint(20) unsigned NOT NULL,
|
|
index_class varchar(265) COLLATE latin1_general_ci DEFAULT NULL ,
|
|
index_object_id int(10) unsigned NOT NULL DEFAULT '0' ,
|
|
index_date_updated int(10) unsigned DEFAULT NULL ,
|
|
PRIMARY KEY (index_id),
|
|
KEY index_date_updated (index_date_updated),
|
|
KEY object (index_class(181),index_object_id)
|
|
) engine=innodb;
|
|
insert into t1 select
|
|
@a:=A.a + 10*B.a + 100*C.a,
|
|
concat('val-', @a),
|
|
123456,
|
|
A.a + 10*B.a
|
|
from
|
|
t0 A, t0 B, t0 C;
|
|
insert into t2 select * from t1;
|
|
# This must have the same query plan as the query below it:
|
|
# type=range, key=index_date_updated, key_len=13
|
|
explain
|
|
select * from t1 force index(index_date_updated)
|
|
where index_date_updated= 10 and index_id < 800;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 range index_date_updated index_date_updated 13 NULL # Using index condition
|
|
# This used to work from the start:
|
|
explain
|
|
select * from t2 force index(index_date_updated)
|
|
where index_date_updated= 10 and index_id < 800;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t2 range index_date_updated index_date_updated 13 NULL # Using index condition
|
|
drop table t0,t1,t2;
|
|
#
|
|
# MDEV-11196: Error:Run-Time Check Failure #2 - Stack around the variable 'key_buff'
|
|
# was corrupted, server crashes in opt_sum_query
|
|
SET @save_optimizer_use_condition_selectivity=@@optimizer_use_condition_selectivity, @@optimizer_use_condition_selectivity=4;
|
|
CREATE TABLE t1 (
|
|
pk INT,
|
|
f1 VARCHAR(3),
|
|
f2 VARCHAR(1024),
|
|
PRIMARY KEY (pk),
|
|
KEY(f2)
|
|
) ENGINE=InnoDB CHARSET utf8 ROW_FORMAT= DYNAMIC;
|
|
INSERT INTO t1 VALUES (1,'foo','abc'),(2,'bar','def');
|
|
SELECT MAX(t2.pk) FROM t1 t2 INNER JOIN t1 t3 ON t2.f1 = t3.f1 WHERE t2.pk <= 4;
|
|
MAX(t2.pk)
|
|
2
|
|
drop table t1;
|
|
CREATE TABLE t1 (
|
|
pk1 INT,
|
|
pk2 INT,
|
|
f1 VARCHAR(3),
|
|
f2 VARCHAR(1021),
|
|
PRIMARY KEY (pk1,pk2),
|
|
KEY(f2)
|
|
) ENGINE=InnoDB CHARSET utf8 ROW_FORMAT= DYNAMIC;
|
|
INSERT INTO t1 VALUES (1,2,'2','abc'),(2,3,'3','def');
|
|
explain format= json
|
|
select * from t1 force index(f2) where pk1 <= 5 and pk2 <=5 and f2 = 'abc' and f1 <= '3';
|
|
EXPLAIN
|
|
{
|
|
"query_block": {
|
|
"select_id": 1,
|
|
"nested_loop": [
|
|
{
|
|
"table": {
|
|
"table_name": "t1",
|
|
"access_type": "range",
|
|
"possible_keys": ["f2"],
|
|
"key": "f2",
|
|
"key_length": "3070",
|
|
"used_key_parts": ["f2", "pk1"],
|
|
"rows": 1,
|
|
"filtered": 100,
|
|
"index_condition": "t1.pk1 <= 5 and t1.pk2 <= 5 and t1.f2 = 'abc'",
|
|
"attached_condition": "t1.f1 <= '3'"
|
|
}
|
|
}
|
|
]
|
|
}
|
|
}
|
|
drop table t1;
|
|
CREATE TABLE t1 (
|
|
f2 INT,
|
|
pk2 INT,
|
|
f1 VARCHAR(3),
|
|
pk1 VARCHAR(1000),
|
|
PRIMARY KEY (pk1,pk2),
|
|
KEY k1(pk1,f2)
|
|
) ENGINE=InnoDB CHARSET utf8 ROW_FORMAT= DYNAMIC;
|
|
INSERT INTO t1 VALUES (1,2,'2','abc'),(2,3,'3','def');
|
|
explain format= json
|
|
select * from t1 force index(k1) where f2 <= 5 and pk2 <=5 and pk1 = 'abc' and f1 <= '3';
|
|
EXPLAIN
|
|
{
|
|
"query_block": {
|
|
"select_id": 1,
|
|
"nested_loop": [
|
|
{
|
|
"table": {
|
|
"table_name": "t1",
|
|
"access_type": "range",
|
|
"possible_keys": ["k1"],
|
|
"key": "k1",
|
|
"key_length": "3011",
|
|
"used_key_parts": ["pk1", "f2", "pk2"],
|
|
"rows": 1,
|
|
"filtered": 100,
|
|
"index_condition": "t1.f2 <= 5 and t1.pk2 <= 5 and t1.pk1 = 'abc'",
|
|
"attached_condition": "t1.f1 <= '3'"
|
|
}
|
|
}
|
|
]
|
|
}
|
|
}
|
|
drop table t1;
|
|
SET optimizer_use_condition_selectivity=@save_optimizer_use_condition_selectivity;
|
|
#
|
|
# MDEV-11172: EXPLAIN shows non-sensical value for key_len with type=index
|
|
#
|
|
CREATE TABLE t1(a INT);
|
|
INSERT INTO t1 VALUES (0),(1),(2),(3),(4),(5),(6),(7),(8),(9);
|
|
CREATE TABLE t2 (
|
|
pk VARCHAR(50),
|
|
a VARCHAR(20),
|
|
KEY k1(a),
|
|
PRIMARY KEY(pk)
|
|
)ENGINE=INNODB;
|
|
INSERT INTO t2 SELECT a,a FROM t1;
|
|
EXPLAIN SELECT pk FROM t2 FORCE INDEX(k1);
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t2 index NULL k1 23 NULL # Using index
|
|
DROP TABLE t1,t2;
|
|
set global innodb_stats_persistent= @innodb_stats_persistent_save;
|
|
set global innodb_stats_persistent_sample_pages= @innodb_stats_persistent_sample_pages_save;
|