127 lines
6.5 KiB
Plaintext
127 lines
6.5 KiB
Plaintext
create database explain_test_db;
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use explain_test_db;
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create table explain_test_table(c int);
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create procedure explain_test_proc()
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BEGIN
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select * from explain_test_table;
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END //
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truncate table performance_schema.events_statements_summary_by_program;
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call explain_test_proc();
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c
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====================================================================
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Testing index for columns OBJECT_TYPE, OBJECT_SCHEMA, OBJECT_NAME
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====================================================================
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############ Explain for Query ####################################
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explain select COUNT_STAR
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from performance_schema.events_statements_summary_by_program
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where OBJECT_TYPE = "impossible";
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id select_type table partitions type possible_keys key key_len ref rows filtered Extra
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1 SIMPLE events_statements_summary_by_program NULL ref PRIMARY PRIMARY 1 const # 100.00 Using where
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############ Explain for Query ####################################
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explain select COUNT_STAR
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from performance_schema.events_statements_summary_by_program
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where OBJECT_TYPE > "impossible";
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id select_type table partitions type possible_keys key key_len ref rows filtered Extra
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1 SIMPLE events_statements_summary_by_program NULL ALL PRIMARY NULL NULL NULL # 33.33 Using where
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############ Explain for Query ####################################
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explain select COUNT_STAR
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from performance_schema.events_statements_summary_by_program
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where OBJECT_TYPE < "2";
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id select_type table partitions type possible_keys key key_len ref rows filtered Extra
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1 SIMPLE events_statements_summary_by_program NULL ALL PRIMARY NULL NULL NULL # 33.33 Using where
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############ Explain for Query ####################################
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explain select COUNT_STAR
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from performance_schema.events_statements_summary_by_program
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where OBJECT_TYPE = "PROCEDURE";
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id select_type table partitions type possible_keys key key_len ref rows filtered Extra
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1 SIMPLE events_statements_summary_by_program NULL ref PRIMARY PRIMARY 1 const # 100.00 Using where
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############ Explain for Query ####################################
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explain select COUNT_STAR
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from performance_schema.events_statements_summary_by_program
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where OBJECT_TYPE = "impossible"
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and OBJECT_SCHEMA = "impossible";
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id select_type table partitions type possible_keys key key_len ref rows filtered Extra
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1 SIMPLE events_statements_summary_by_program NULL ref PRIMARY PRIMARY 259 const,const # 100.00 Using where
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############ Explain for Query ####################################
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explain select COUNT_STAR
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from performance_schema.events_statements_summary_by_program
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where OBJECT_TYPE = "PROCEDURE"
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and OBJECT_SCHEMA = "impossible";
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id select_type table partitions type possible_keys key key_len ref rows filtered Extra
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1 SIMPLE events_statements_summary_by_program NULL ref PRIMARY PRIMARY 259 const,const # 100.00 Using where
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############ Explain for Query ####################################
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explain select COUNT_STAR
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from performance_schema.events_statements_summary_by_program
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where OBJECT_TYPE = "PROCEDURE"
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and OBJECT_SCHEMA > "impossible";
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id select_type table partitions type possible_keys key key_len ref rows filtered Extra
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1 SIMPLE events_statements_summary_by_program NULL ref PRIMARY PRIMARY 1 const # 33.33 Using where
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############ Explain for Query ####################################
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explain select COUNT_STAR
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from performance_schema.events_statements_summary_by_program
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where OBJECT_TYPE = "PROCEDURE"
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and OBJECT_SCHEMA < "2";
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id select_type table partitions type possible_keys key key_len ref rows filtered Extra
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1 SIMPLE events_statements_summary_by_program NULL ref PRIMARY PRIMARY 1 const # 33.33 Using where
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############ Explain for Query ####################################
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explain select COUNT_STAR
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from performance_schema.events_statements_summary_by_program
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where OBJECT_TYPE = "PROCEDURE"
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and OBJECT_SCHEMA = "explain_test_db";
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id select_type table partitions type possible_keys key key_len ref rows filtered Extra
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1 SIMPLE events_statements_summary_by_program NULL ref PRIMARY PRIMARY 259 const,const # 100.00 Using where
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############ Explain for Query ####################################
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explain select COUNT_STAR
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from performance_schema.events_statements_summary_by_program
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where OBJECT_TYPE = "impossible"
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and OBJECT_SCHEMA = "impossible"
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and OBJECT_NAME = "impossible";
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id select_type table partitions type possible_keys key key_len ref rows filtered Extra
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1 SIMPLE NULL NULL NULL NULL NULL NULL NULL # NULL no matching row in const table
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############ Explain for Query ####################################
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explain select COUNT_STAR
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from performance_schema.events_statements_summary_by_program
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where OBJECT_TYPE = "PROCEDURE"
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and OBJECT_SCHEMA = "explain_test_db"
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and OBJECT_NAME = "impossible";
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id select_type table partitions type possible_keys key key_len ref rows filtered Extra
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1 SIMPLE NULL NULL NULL NULL NULL NULL NULL # NULL no matching row in const table
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############ Explain for Query ####################################
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explain select COUNT_STAR
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from performance_schema.events_statements_summary_by_program
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where OBJECT_TYPE = "PROCEDURE"
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and OBJECT_SCHEMA = "explain_test_db"
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and OBJECT_NAME > "impossible";
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id select_type table partitions type possible_keys key key_len ref rows filtered Extra
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1 SIMPLE events_statements_summary_by_program NULL ref PRIMARY PRIMARY 259 const,const # 33.33 Using where
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############ Explain for Query ####################################
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explain select COUNT_STAR
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from performance_schema.events_statements_summary_by_program
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where OBJECT_TYPE = "PROCEDURE"
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and OBJECT_SCHEMA = "explain_test_db"
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and OBJECT_NAME < "2";
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id select_type table partitions type possible_keys key key_len ref rows filtered Extra
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1 SIMPLE events_statements_summary_by_program NULL ref PRIMARY PRIMARY 259 const,const # 33.33 Using where
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############ Explain for Query ####################################
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explain select COUNT_STAR
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from performance_schema.events_statements_summary_by_program
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where OBJECT_TYPE = "PROCEDURE"
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and OBJECT_SCHEMA = "explain_test_db"
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and OBJECT_NAME = "explain_test_proc";
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id select_type table partitions type possible_keys key key_len ref rows filtered Extra
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1 SIMPLE events_statements_summary_by_program NULL const PRIMARY PRIMARY 517 const,const,const # 100.00 NULL
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############# Explain End #########################################
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flush status;
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select COUNT_STAR
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from performance_schema.events_statements_summary_by_program
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where OBJECT_TYPE = "PROCEDURE"
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and OBJECT_SCHEMA = "explain_test_db"
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and OBJECT_NAME = "explain_test_proc";
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COUNT_STAR
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#
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OK: handler_read_key incremented
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drop procedure explain_test_proc;
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drop table explain_test_db.explain_test_table;
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drop database explain_test_db;
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