name : mysql_performance_tables.sql -- -- PERFORMANCE SCHEMA INSTALLATION -- Note that this script is also reused by mysql_upgrade, -- so we have to be very careful here to not destroy any -- existing database named 'performance_schema' if it -- can contain user data. -- In case of downgrade, it's ok to drop unknown tables -- from a future version, as long as they belong to the -- performance schema engine. -- set @have_old_pfs= (select count(*) from information_schema.schemata where schema_name='performance_schema'); SET @cmd="SET @broken_tables = (select count(*) from information_schema.tables where engine != 'PERFORMANCE_SCHEMA' and table_schema='performance_schema')"; -- Work around for bug#49542 SET @str = IF(@have_old_pfs = 1, @cmd, 'SET @broken_tables = 0'); PREPARE stmt FROM @str; EXECUTE stmt; DROP PREPARE stmt; SET @cmd="SET @broken_views = (select count(*) from information_schema.views where table_schema='performance_schema')"; -- Work around for bug#49542 SET @str = IF(@have_old_pfs = 1, @cmd, 'SET @broken_views = 0'); PREPARE stmt FROM @str; EXECUTE stmt; DROP PREPARE stmt; SET @broken_routines = (select count(*) from mysql.proc where db='performance_schema'); SET @broken_events = (select count(*) from mysql.event where db='performance_schema'); SET @broken_pfs= (select @broken_tables + @broken_views + @broken_routines + @broken_events); -- -- The performance schema database. -- Only drop and create the database if this is safe (no broken_pfs). -- This database is created, even in --without-perfschema builds, -- so that the database name is always reserved by the MySQL implementation. -- SET @cmd= "DROP DATABASE IF EXISTS performance_schema"; SET @str = IF(@broken_pfs = 0, @cmd, 'SET @dummy = 0'); PREPARE stmt FROM @str; EXECUTE stmt; DROP PREPARE stmt; SET @cmd= "CREATE DATABASE performance_schema character set utf8mb3"; SET @str = IF(@broken_pfs = 0, @cmd, 'SET @dummy = 0'); PREPARE stmt FROM @str; EXECUTE stmt; DROP PREPARE stmt;