Bug#49823: mysql_upgrade fatal error due to general_log / slow_low CSV NULL

The problem was that the CSV storage engine does not support NULL
fields, yet in some early 5.1 version the log tables (general_log
and slow_log) were created with null fields. On top of this, when
altering a CSV table column, all fields of the table must be NOT
NULL otherwise the alteration fails.

The solution is to ensure that during upgrade all columns of the
log tables are NOT NULL.

mysql-test/r/log_tables_upgrade.result:
  Add test case result for Bug#49823.
mysql-test/std_data/bug49823.CSV:
  Sample data for test.
mysql-test/std_data/bug49823.frm:
  Add a CSV table which mimics the general_log table, except that
  it contains a nullable column.
mysql-test/t/log_tables_upgrade.test:
  Add test case for Bug#49823.
scripts/mysql_system_tables_fix.sql:
  Ensure that all columns of the log tables are NOT NULL.

mysql-test/r/log_tables_upgrade.result

+#
+# Bug#49823: mysql_upgrade fatal error due to general_log / slow_low CSV NULL
+#
+USE test;
+SET @saved_general_log = @@GLOBAL.general_log;
+SET GLOBAL general_log = OFF;
+USE mysql;
+FLUSH TABLES;
+REPAIR TABLE test.bug49823;
+Table	Op	Msg_type	Msg_text
+test.bug49823	repair	status	OK
+RENAME TABLE general_log TO renamed_general_log;
+RENAME TABLE test.bug49823 TO general_log;
+mtr.global_suppressions                            OK
+mtr.test_suppressions                              OK
+mysql.columns_priv                                 OK
+mysql.db                                           OK
+mysql.event                                        OK
+mysql.func                                         OK
+mysql.general_log
+Error    : You can't use locks with log tables.
+status   : OK
+mysql.help_category                                OK
+mysql.help_keyword                                 OK
+mysql.help_relation                                OK
+mysql.help_topic                                   OK
+mysql.host                                         OK
+mysql.ndb_binlog_index                             OK
+mysql.plugin                                       OK
+mysql.proc                                         OK
+mysql.procs_priv                                   OK
+mysql.renamed_general_log                          OK
+mysql.servers                                      OK
+mysql.slow_log
+Error    : You can't use locks with log tables.
+status   : OK
+mysql.tables_priv                                  OK
+mysql.time_zone                                    OK
+mysql.time_zone_leap_second                        OK
+mysql.time_zone_name                               OK
+mysql.time_zone_transition                         OK
+mysql.time_zone_transition_type                    OK
+mysql.user                                         OK
+DROP TABLE general_log;
+RENAME TABLE renamed_general_log TO general_log;
+SET GLOBAL general_log = @saved_general_log;
+USE test;

mysql-test/std_data/bug49823.CSV

+"2010-02-26 13:32:26","root[root] @ localhost []",2,1,"Query","SELECT 1"

mysql-test/t/log_tables_upgrade.test

+--source include/not_embedded.inc
+--source include/have_csv.inc
+
+# Only run test if "mysql_upgrade" is found
+--require r/have_mysql_upgrade.result
+--disable_query_log
+select LENGTH("$MYSQL_UPGRADE")>0 as have_mysql_upgrade;
+--enable_query_log
+
+--echo #
+--echo # Bug#49823: mysql_upgrade fatal error due to general_log / slow_low CSV NULL
+--echo #
+
+USE test;
+
+let $MYSQLD_DATADIR= `SELECT @@datadir`;
+copy_file std_data/bug49823.frm $MYSQLD_DATADIR/test/bug49823.frm;
+copy_file std_data/bug49823.CSM $MYSQLD_DATADIR/test/bug49823.CSM;
+copy_file std_data/bug49823.CSV $MYSQLD_DATADIR/test/bug49823.CSV;
+
+SET @saved_general_log = @@GLOBAL.general_log;
+SET GLOBAL general_log = OFF;
+USE mysql;
+FLUSH TABLES;
+REPAIR TABLE test.bug49823;
+RENAME TABLE general_log TO renamed_general_log;
+RENAME TABLE test.bug49823 TO general_log;
+--exec $MYSQL_UPGRADE --skip-verbose --force 2>&1
+DROP TABLE general_log;
+RENAME TABLE renamed_general_log TO general_log;
+SET GLOBAL general_log = @saved_general_log;
+USE test;

scripts/mysql_system_tables_fix.sql

@@ -221,12 +221,29 @@ ALTER TABLE func
 
 SET @old_log_state = @@global.general_log;
 SET GLOBAL general_log = 'OFF';
-ALTER TABLE general_log MODIFY COLUMN server_id INTEGER UNSIGNED NOT NULL;
+ALTER TABLE general_log
+  MODIFY event_time TIMESTAMP NOT NULL,
+  MODIFY user_host MEDIUMTEXT NOT NULL,
+  MODIFY thread_id INTEGER NOT NULL,
+  MODIFY server_id INTEGER UNSIGNED NOT NULL,
+  MODIFY command_type VARCHAR(64) NOT NULL,
+  MODIFY argument MEDIUMTEXT NOT NULL;
 SET GLOBAL general_log = @old_log_state;
 
 SET @old_log_state = @@global.slow_query_log;
 SET GLOBAL slow_query_log = 'OFF';
-ALTER TABLE slow_log MODIFY COLUMN server_id INTEGER UNSIGNED NOT NULL;
+ALTER TABLE slow_log
+  MODIFY start_time TIMESTAMP NOT NULL,
+  MODIFY user_host MEDIUMTEXT NOT NULL,
+  MODIFY query_time TIME NOT NULL,
+  MODIFY lock_time TIME NOT NULL,
+  MODIFY rows_sent INTEGER NOT NULL,
+  MODIFY rows_examined INTEGER NOT NULL,
+  MODIFY db VARCHAR(512) NOT NULL,
+  MODIFY last_insert_id INTEGER NOT NULL,
+  MODIFY insert_id INTEGER NOT NULL,
+  MODIFY server_id INTEGER UNSIGNED NOT NULL,
+  MODIFY sql_text MEDIUMTEXT NOT NULL;
 SET GLOBAL slow_query_log = @old_log_state;
 
 #