MDEV-14882 mysql_upgrade performs unnecessary conversions back and forth

avoid round-robin conversions, if the column is MODIFY-ed,
it should always be modified to its final definition, not to some
intermediate state.

also avoid other unconditional changes, like
  ALTER TABLE event DROP PRIMARY KEY;
  ALTER TABLE event ADD PRIMARY KEY(db, name);

1 files changed, 30 insertions, 20 deletions

diff --git a/scripts/mysql_system_tables_fix.sql b/scripts/mysql_system_tables_fix.sql
index 1bb601ef5f9..194b1615c2b 100644
--- a/scripts/mysql_system_tables_fix.sql
+++ b/scripts/mysql_system_tables_fix.sql
@@ -1,5 +1,5 @@
 -- Copyright (C) 2003, 2013 Oracle and/or its affiliates.
--- Copyright (C) 2010, 2014 SkySQL Ab.
+-- Copyright (C) 2010, 2018 MariaDB Corporation
 --
 -- This program is free software; you can redistribute it and/or modify
 -- it under the terms of the GNU General Public License as published by
@@ -27,15 +27,24 @@
 set sql_mode='';
 set storage_engine=MyISAM;
 
-ALTER TABLE user add File_priv enum('N','Y') COLLATE utf8_general_ci NOT NULL;
+ALTER TABLE user add File_priv enum('N','Y') COLLATE utf8_general_ci DEFAULT 'N' NOT NULL;
 
 # Detect whether or not we had the Grant_priv column
 SET @hadGrantPriv:=0;
 SELECT @hadGrantPriv:=1 FROM user WHERE Grant_priv LIKE '%';
 
-ALTER TABLE user add Grant_priv enum('N','Y') COLLATE utf8_general_ci NOT NULL,add References_priv enum('N','Y') COLLATE utf8_general_ci NOT NULL,add Index_priv enum('N','Y') COLLATE utf8_general_ci NOT NULL,add Alter_priv enum('N','Y') COLLATE utf8_general_ci NOT NULL;
-ALTER TABLE host add Grant_priv enum('N','Y') NOT NULL,add References_priv enum('N','Y') COLLATE utf8_general_ci NOT NULL,add Index_priv enum('N','Y') COLLATE utf8_general_ci NOT NULL,add Alter_priv enum('N','Y') COLLATE utf8_general_ci NOT NULL;
-ALTER TABLE db add Grant_priv enum('N','Y') COLLATE utf8_general_ci NOT NULL,add References_priv enum('N','Y') COLLATE utf8_general_ci NOT NULL,add Index_priv enum('N','Y') COLLATE utf8_general_ci NOT NULL,add Alter_priv enum('N','Y') COLLATE utf8_general_ci NOT NULL;
+ALTER TABLE user add Grant_priv enum('N','Y') COLLATE utf8_general_ci DEFAULT 'N' NOT NULL,
+                 add References_priv enum('N','Y') COLLATE utf8_general_ci DEFAULT 'N' NOT NULL,
+                 add Index_priv enum('N','Y') COLLATE utf8_general_ci DEFAULT 'N' NOT NULL,
+                 add Alter_priv enum('N','Y') COLLATE utf8_general_ci DEFAULT 'N' NOT NULL;
+ALTER TABLE host add Grant_priv enum('N','Y') COLLATE utf8_general_ci DEFAULT 'N' NOT NULL,
+                 add References_priv enum('N','Y') COLLATE utf8_general_ci DEFAULT 'N' NOT NULL,
+                 add Index_priv enum('N','Y') COLLATE utf8_general_ci DEFAULT 'N' NOT NULL,
+                 add Alter_priv enum('N','Y') COLLATE utf8_general_ci DEFAULT 'N' NOT NULL;
+ALTER TABLE db add Grant_priv enum('N','Y') COLLATE utf8_general_ci DEFAULT 'N' NOT NULL,
+               add References_priv enum('N','Y') COLLATE utf8_general_ci DEFAULT 'N' NOT NULL,
+               add Index_priv enum('N','Y') COLLATE utf8_general_ci DEFAULT 'N' NOT NULL,
+               add Alter_priv enum('N','Y') COLLATE utf8_general_ci DEFAULT 'N' NOT NULL;
 
 # Fix privileges for old tables
 UPDATE user SET Grant_priv=File_priv,References_priv=Create_priv,Index_priv=Create_priv,Alter_priv=Create_priv WHERE @hadGrantPriv = 0;
@@ -47,11 +56,11 @@ UPDATE host SET References_priv=Create_priv,Index_priv=Create_priv,Alter_priv=Cr
 # Adding columns needed by GRANT .. REQUIRE (openssl)
 
 ALTER TABLE user
-ADD ssl_type enum('','ANY','X509', 'SPECIFIED') COLLATE utf8_general_ci NOT NULL,
+ADD ssl_type enum('','ANY','X509', 'SPECIFIED') DEFAULT '' NOT NULL,
 ADD ssl_cipher BLOB NOT NULL,
 ADD x509_issuer BLOB NOT NULL,
 ADD x509_subject BLOB NOT NULL;
-ALTER TABLE user MODIFY ssl_type enum('','ANY','X509', 'SPECIFIED') NOT NULL;
+ALTER TABLE user MODIFY ssl_type enum('','ANY','X509', 'SPECIFIED') DEFAULT '' NOT NULL;
 
 #
 # tables_priv
@@ -62,9 +71,9 @@ ALTER TABLE tables_priv
 ALTER TABLE tables_priv
   MODIFY Host char(60) NOT NULL default '',
   MODIFY Db char(64) NOT NULL default '',
-  MODIFY User char(80) NOT NULL default '',
+  MODIFY User char(80) binary NOT NULL default '',
   MODIFY Table_name char(64) NOT NULL default '',
-  MODIFY Grantor char(141) NOT NULL default '',
+  MODIFY Grantor char(141) COLLATE utf8_bin NOT NULL default '',
   ENGINE=MyISAM,
   CONVERT TO CHARACTER SET utf8 COLLATE utf8_bin;
 
@@ -90,7 +99,7 @@ ALTER TABLE columns_priv
 ALTER TABLE columns_priv
   MODIFY Host char(60) NOT NULL default '',
   MODIFY Db char(64) NOT NULL default '',
-  MODIFY User char(80) NOT NULL default '',
+  MODIFY User char(80) binary NOT NULL default '',
   MODIFY Table_name char(64) NOT NULL default '',
   MODIFY Column_name char(64) NOT NULL default '',
   ENGINE=MyISAM,
@@ -161,7 +170,7 @@ alter table func comment='User defined functions';
 # and reset all char columns to correct width
 ALTER TABLE user
   MODIFY Host char(60) NOT NULL default '',
-  MODIFY User char(80) NOT NULL default '',
+  MODIFY User char(80) binary NOT NULL default '',
   ENGINE=MyISAM, CONVERT TO CHARACTER SET utf8 COLLATE utf8_bin;
 ALTER TABLE user
   MODIFY Password char(41) character set latin1 collate latin1_bin NOT NULL default '',
@@ -191,7 +200,7 @@ ALTER TABLE user
 ALTER TABLE db
   MODIFY Host char(60) NOT NULL default '',
   MODIFY Db char(64) NOT NULL default '',
-  MODIFY User char(80) NOT NULL default '',
+  MODIFY User char(80) binary NOT NULL default '',
   ENGINE=MyISAM, CONVERT TO CHARACTER SET utf8 COLLATE utf8_bin;
 ALTER TABLE db
   MODIFY  Select_priv enum('N','Y') COLLATE utf8_general_ci DEFAULT 'N' NOT NULL,
@@ -451,7 +460,7 @@ ALTER TABLE proc  MODIFY db
                   MODIFY definer
                          char(141) collate utf8_bin DEFAULT '' NOT NULL,
                   MODIFY comment
-                         char(64) collate utf8_bin DEFAULT '' NOT NULL;
+                         text collate utf8_bin NOT NULL;
 
 ALTER TABLE proc ADD character_set_client
                      char(32) collate utf8_bin DEFAULT NULL
@@ -515,19 +524,18 @@ ALTER TABLE proc MODIFY comment
 SET @hadEventPriv := 0;
 SELECT @hadEventPriv :=1 FROM user WHERE Event_priv LIKE '%';
 
-ALTER TABLE user add Event_priv enum('N','Y') character set utf8 DEFAULT 'N' NOT NULL AFTER Create_user_priv;
+ALTER TABLE user ADD Event_priv enum('N','Y') character set utf8 DEFAULT 'N' NOT NULL AFTER Create_user_priv;
 ALTER TABLE user MODIFY Event_priv enum('N','Y') character set utf8 DEFAULT 'N' NOT NULL AFTER Create_user_priv;
 
 UPDATE user SET Event_priv=Super_priv WHERE @hadEventPriv = 0;
 
-ALTER TABLE db add Event_priv enum('N','Y') character set utf8 DEFAULT 'N' NOT NULL;
+ALTER TABLE db ADD Event_priv enum('N','Y') character set utf8 DEFAULT 'N' NOT NULL;
 ALTER TABLE db MODIFY Event_priv enum('N','Y') character set utf8 DEFAULT 'N' NOT NULL;
 
 #
 # EVENT table
 #
-ALTER TABLE event DROP PRIMARY KEY;
-ALTER TABLE event ADD PRIMARY KEY(db, name);
+ALTER TABLE event DROP PRIMARY KEY, ADD PRIMARY KEY(db, name);
 # Add sql_mode column just in case.
 ALTER TABLE event ADD sql_mode set ('IGNORE_BAD_TABLE_OPTIONS') AFTER on_completion;
 # Update list of sql_mode values.
@@ -567,8 +575,8 @@ ALTER TABLE event MODIFY sql_mode
                             ) DEFAULT '' NOT NULL AFTER on_completion;
 ALTER TABLE event MODIFY name char(64) CHARACTER SET utf8 NOT NULL default '';
 
-ALTER TABLE event MODIFY COLUMN originator INT UNSIGNED NOT NULL;
 ALTER TABLE event ADD COLUMN originator INT UNSIGNED NOT NULL AFTER comment;
+ALTER TABLE event MODIFY COLUMN originator INT UNSIGNED NOT NULL;
 
 ALTER TABLE event MODIFY COLUMN status ENUM('ENABLED','DISABLED','SLAVESIDE_DISABLED') NOT NULL default 'ENABLED';
 
@@ -630,10 +638,12 @@ ALTER TABLE user MODIFY Create_tablespace_priv enum('N','Y') COLLATE utf8_genera
 
 UPDATE user SET Create_tablespace_priv = Super_priv WHERE @hadCreateTablespacePriv = 0;
 
-ALTER TABLE user ADD plugin char(64) DEFAULT '',  ADD authentication_string TEXT;
+ALTER TABLE user ADD plugin char(64) CHARACTER SET latin1 DEFAULT '' NOT NULL,
+                 ADD authentication_string TEXT NOT NULL;
+ALTER TABLE user MODIFY plugin char(64) CHARACTER SET latin1 DEFAULT '' NOT NULL,
+                 MODIFY authentication_string TEXT NOT NULL;
 ALTER TABLE user ADD password_expired ENUM('N', 'Y') COLLATE utf8_general_ci DEFAULT 'N' NOT NULL;
 ALTER TABLE user ADD is_role enum('N', 'Y') COLLATE utf8_general_ci DEFAULT 'N' NOT NULL;
-ALTER TABLE user MODIFY plugin char(64) CHARACTER SET latin1 DEFAULT '' NOT NULL, MODIFY authentication_string TEXT NOT NULL;
 -- Somewhere above, we ran ALTER TABLE user .... CONVERT TO CHARACTER SET utf8 COLLATE utf8_bin.
 --  we want password_expired column to have collation utf8_general_ci.
 ALTER TABLE user MODIFY password_expired ENUM('N', 'Y') COLLATE utf8_general_ci DEFAULT 'N' NOT NULL;