1 files changed, 55 insertions, 0 deletions
diff --git a/scripts/mysql_performance_tables.sql b/scripts/mysql_performance_tables.sql
new file mode 100644
index 00000000..3a7d0ef5
--- /dev/null
+++ b/scripts/mysql_performance_tables.sql
@@ -0,0 +1,55 @@
+--
+-- 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;