WL#6391: Hide DD tables.

This worklog prohibits access to the internal tables
of the transactional data dictionary (DD). The worklog
implements the following main changes:

1. Remove unused data structures and plugin usage. In
   particular, please note that the 'system_database()'
   handlerton function has been removed.

2. Prohibit access for usage of DD tables from:

   - SQL statements.
   - Foreign key constraints.
   - Stored programs.
   - Replication (also cross version).

   Access is accepted if the thread executing the
   statement is a DD system thread. For external threads,
   i.e., representing an external client, access is accepted
   if the table is a DDSE table (e.g. the 'innodb_*_stats'
   tables), and the statement is DML.

3. Add a debug flag 'skip_dd_table_access_check' to allow
   DD table access in debug builds. Rewrite tests to set
   this flag when needing access to the DD tables. Please
   note that great care must be taken when this flag is
   used. If using DML to update the contents of the DD
   tables directly, without any corresponding updates
   in the storage engine or DD cache, invariants that
   the server expectes to hold will be broken, and a
   malfunctioning server is to be expected. The same
   goes for DDL; with a change in the definitions of the
   DD tables, it is to be expected that the server will
   not work as intended.

4. Rewrite tests that currently access DD tables to set
   the debug flag above. Separate out specific parts of
   tests to only be run on debug builds, if the test
   previously could run on non-debug builds as well.

5. Take into account that the access check mechanism
   may be invoked from the unit tests; check that the
   Dictionary instance exists before calling it.

TODO: Dependencies on other worklogs:

1. Remove exception regarding queries against the
   st_spatial_refrerence_systems table (WL#9059).
2. Prohibit access to altering or dropping the system
   tablespace (WL#7141).

Author: ssorumgard

mysql-test/include/dd_schema_definition.inc renamed to mysql-test/include/dd_schema_definition_debug.inc

@@ -7,8 +7,12 @@
 # definitions of the DD tables need to be updated to match
 # the old test results."
 
+--source include/have_debug.inc
+
 use mysql;
 
+SET SESSION debug= '+d,skip_dd_table_access_check';
+
 # The DD database id
 let $dd_schema_id= `SELECT id FROM schemata
   WHERE name= 'mysql'`;
@@ -75,3 +79,5 @@ eval SELECT * FROM indexes
 eval SELECT * FROM index_column_usage
   WHERE index_id IN ($dd_index_ids)
   ORDER BY index_id, column_id;
+
+SET SESSION debug= '-d,skip_dd_table_access_check';

mysql-test/r/audit_plugin_2.result

@@ -1625,6 +1625,11 @@ SET @@null_audit_event_order_check = 'MYSQL_AUDIT_COMMAND_START;command_id="<exp
                                           'MYSQL_AUDIT_PARSE_POSTPARSE;;;'
                                           'MYSQL_AUDIT_GENERAL_LOG;;;'
                                           'MYSQL_AUDIT_QUERY_START;sql_command_id="0";;'
+                                          'MYSQL_AUDIT_GENERAL_ERROR;;;'
+                                          'MYSQL_AUDIT_GENERAL_ERROR;;;'
+                                          'MYSQL_AUDIT_GENERAL_ERROR;;;'
+                                          'MYSQL_AUDIT_GENERAL_ERROR;;;'
+                                          'MYSQL_AUDIT_GENERAL_ERROR;;;'
                                           'MYSQL_AUDIT_QUERY_STATUS_END;sql_command_id="0";;'
                                           'MYSQL_AUDIT_GENERAL_RESULT;;;'
                                           'MYSQL_AUDIT_GENERAL_STATUS;;;'

mysql-test/r/dd_bootstrap.result

@@ -1,88 +1,49 @@
-# Preparation: Shut server down.
-#
-# 1. Try restart after setting an invalid version.
-# ------------------------------------------------
-# 1.1 Create bootstrap file.
-# 1.2 First start the server with --initialize, and update the version.
-# 1.3 Restart the server against DDIR - should fail.
-# 1.4 Look for warning.
-#     Dictionary version warning found 1 times.
-# 1.5 Delete bootstrap file, log file and datadir.
 #
-# 2. Try restart after dropping the version table.
-# ------------------------------------------------
-# 2.1 Create bootstrap file.
-# 2.2 First start the server with --initialize, and drop the version table: Should fail.
-# 2.3 Look for error.
-#     Drop table error found 1 times.
-# 2.4 Restart the server against DDIR - should fail.
-# 2.5 Look for error.
-#     Data Dictionary initialization error found 1 times.
-# 2.6 Delete bootstrap file, log file and datadir.
+# This file contains bootstrap test cases that do not
+# need to be run with a debug build. See also the 
+# test file 'dd_bootstrap_debug.test' for debug
+# test cases.
 #
-# 3. Try restart after dropping the tables table.
-# -----------------------------------------------
-# 3.1 Create bootstrap file.
-# 3.2 First start the server with --initialize, and drop the tables table: Should fail.
-# 3.3 Look for error.
-#     Drop table error found 1 times.
-# 3.4 Restart the server against DDIR - should fail.
-# 3.5 Look for error.
-#     Data Dictionary initialization error found 1 times.
-# 3.6 Delete bootstrap file, log file and datadir.
+# Preparation: Shut server down.
 #
-# 4. Try restart after dropping the time_zone_transition_type table.
+# 1. Try restart after dropping the time_zone_transition_type table.
 # ------------------------------------------------------------------
-# 4.1 Create bootstrap file.
-# 4.2 First start the server with --initialize, and drop the time_zone_transition_type table.
-# 4.3 Restart the server against DDIR - should succeed.
-# 4.4 Shut server down.
-# 4.5 Look for warning.
+# 1.1 Create bootstrap file.
+# 1.2 First start the server with --initialize, and drop the time_zone_transition_type table.
+# 1.3 Restart the server against DDIR - should succeed.
+# 1.4 Shut server down.
+# 1.5 Look for warning.
 #     Time zone table warning found 1 times.
-# 4.6 Delete bootstrap file, log file and datadir.
+# 1.6 Delete bootstrap file, log file and datadir.
 #
-# 5. Try restart after deleting the version tablespace.
+# 2. Try restart after deleting the version tablespace.
 # -----------------------------------------------------
-# 5.1 First start the server with --initialize.
-# 5.2 Delete the physical tablespace file for mysql.version.
-# 5.3 Restart the server against DDIR - should fail.
-# 5.4 Look for error.
+# 2.1 First start the server with --initialize.
+# 2.2 Delete the physical tablespace file for mysql.version.
+# 2.3 Restart the server against DDIR - should fail.
+# 2.4 Look for error.
 #     Tablespace error found 1 times.
-# 5.5 Delete log file and datadir.
-#
-# 6. Try restart after altering the schemata table.
-# -------------------------------------------------
-# 6.1 Create bootstrap file.
-# 6.2 First start the server with --initialize, and alter the schemata table.
-# 6.3 Restart the server against DDIR.
-# 6.4 Connect as root.
-# 6.5 Verify that the modified table is present.
-SELECT comment FROM mysql.tables WHERE name='schemata';
-comment
-Altered table
-# 6.6 Shut server down.
-# 6.7 Close the test connection.
-# 6.8 Delete bootstrap file, log file and datadir.
+# 2.5 Delete log file and datadir.
 #
-# 7. Try restart on a non-existing datadir.
+# 3. Try restart on a non-existing datadir.
 # -----------------------------------------
-# 7.1 Restart the server against non-existing DDIR - should fail.
-# 7.2 Look for error.
+# 3.1 Restart the server against non-existing DDIR - should fail.
+# 3.2 Look for error.
 #     Datadir error found 1 times.
-# 7.3 Delete log file and datadir.
+# 3.3 Delete log file and datadir.
 #
-# 8. Try restart on an empty datadir (non-existing mysql dir).
+# 4. Try restart on an empty datadir (non-existing mysql dir).
 # ------------------------------------------------------------
-# 8.1 Restart the server against existing but empty DDIR - should fail.
-# 8.2 Look for error.
+# 4.1 Restart the server against existing but empty DDIR - should fail.
+# 4.2 Look for error.
 #     InnoDB file open error found 1 times.
-# 8.3 Delete log file and datadir.
+# 4.3 Delete log file and datadir.
 #
-# 9. Try restart on an empty mysql dir.
+# 5. Try restart on an empty mysql dir.
 # -------------------------------------
-# 9.1 Restart the server against existing but empty mysql dir - should fail.
-# 9.2 Look for error.
+# 5.1 Restart the server against existing but empty mysql dir - should fail.
+# 5.2 Look for error.
 #     InnoDB file open error found 1 times.
-# 9.3 Delete log file and datadir.
+# 5.3 Delete log file and datadir.
 #
 # Cleanup: Restarting the server against default datadir.

mysql-test/r/dd_bootstrap_debug.result

@@ -0,0 +1,56 @@
+#
+# This file contains bootstrap test cases that
+# need to be run with a debug build. See also the
+# test file 'dd_bootstrap.test' for test cases
+# that can be run with a non-debug server build.
+#
+# Preparation: Shut server down.
+#
+# 1. Try restart after setting an invalid version.
+# ------------------------------------------------
+# 1.1 Create bootstrap file.
+# 1.2 First start the server with --initialize, and update the version.
+# 1.3 Restart the server against DDIR - should fail.
+# 1.4 Look for warning.
+#     Dictionary version warning found 1 times.
+# 1.5 Delete bootstrap file, log file and datadir.
+#
+# 2. Try restart after dropping the version table.
+# ------------------------------------------------
+# 2.1 Create bootstrap file.
+# 2.2 First start the server with --initialize, and drop the version table: Should fail.
+# 2.3 Look for error.
+#     Drop table error found 1 times.
+# 2.4 Restart the server against DDIR - should fail.
+# 2.5 Look for error.
+#     Data Dictionary initialization error found 1 times.
+# 2.6 Delete bootstrap file, log file and datadir.
+#
+# 3. Try restart after dropping the tables table.
+# -----------------------------------------------
+# 3.1 Create bootstrap file.
+# 3.2 First start the server with --initialize, and drop the tables table: Should fail.
+# 3.3 Look for error.
+#     Drop table error found 1 times.
+# 3.4 Restart the server against DDIR - should fail.
+# 3.5 Look for error.
+#     Data Dictionary initialization error found 1 times.
+# 3.6 Delete bootstrap file, log file and datadir.
+#
+# 4. Try restart after altering the schemata table.
+# -------------------------------------------------
+# 4.1 Create bootstrap file.
+# 4.2 First start the server with --initialize, and alter the schemata table.
+# 4.3 Restart the server against DDIR.
+# 4.4 Connect as root.
+# 4.5 Verify that the modified table is present.
+SET SESSION debug= '+d,skip_dd_table_access_check';
+SELECT comment FROM mysql.tables WHERE name='schemata';
+comment
+Altered table
+SET SESSION debug= '-d,skip_dd_table_access_check';
+# 4.6 Shut server down.
+# 4.7 Close the test connection.
+# 4.8 Delete bootstrap file, log file and datadir.
+#
+# Cleanup: Restarting the server against default datadir.

mysql-test/r/dd_debug.result

@@ -80,6 +80,7 @@ SET DEBUG= '-d, fail_while_dropping_dd_object';
 #       will be addressed in WL#7743.
 DROP SCHEMA s1;
 ERROR HY000: Can't drop database 's1'; database doesn't exist
+SET SESSION debug= '+d,skip_dd_table_access_check';
 SELECT COUNT(*) FROM mysql.schemata WHERE name LIKE 's1';
 COUNT(*)
 1
@@ -88,6 +89,7 @@ DROP SCHEMA s1;
 SELECT COUNT(*) FROM mysql.schemata WHERE name LIKE 's1';
 COUNT(*)
 0
+SET SESSION debug= '-d,skip_dd_table_access_check';
 ###################################################################
 #
 # 2. Tables
@@ -184,6 +186,7 @@ SET DEBUG= '-d, fail_while_dropping_dd_object';
 #       ts1 in mysql.tablespaces.
 DROP TABLESPACE ts1;
 ERROR HY000: Failed to drop TABLESPACE ts1
+SET SESSION debug= '+d,skip_dd_table_access_check';
 SELECT COUNT(*) FROM mysql.tablespaces WHERE name LIKE 'ts1';
 COUNT(*)
 1
@@ -195,4 +198,5 @@ DROP TABLESPACE ts1;
 SELECT COUNT(*) FROM mysql.tablespaces WHERE name LIKE 'ts1';
 COUNT(*)
 0
+SET SESSION debug= '-d,skip_dd_table_access_check';
 ###################################################################

mysql-test/r/dd_is_concurrency.result

@@ -1,3 +1,4 @@
+SET GLOBAL debug= '+d,skip_dd_table_access_check';
 use test;
 CREATE VIEW not_system_view AS
 SELECT name as table_name, mysql_version_id FROM mysql.tables;
@@ -129,3 +130,4 @@ connection con1;
 disconnect con1;
 connection default;
 DROP VIEW not_system_view;
+SET GLOBAL debug= '-d,skip_dd_table_access_check';

mysql-test/r/dd_schema_definition_ci.result renamed to mysql-test/r/dd_schema_definition_debug_ci.result

@@ -1,4 +1,5 @@
 use mysql;
+SET SESSION debug= '+d,skip_dd_table_access_check';
 #
 # Subset of definitions from tables, not including
 # timestamps, partitioning, view definitions and
@@ -446,3 +447,4 @@ index_id	ordinal_position	column_id	length	order	hidden
 81	1	281	8	ASC	0
 82	1	282	192	ASC	0
 83	1	283	8	ASC	0
+SET SESSION debug= '-d,skip_dd_table_access_check';

mysql-test/r/dd_schema_definition_cs.result renamed to mysql-test/r/dd_schema_definition_debug_cs.result

@@ -1,4 +1,5 @@
 use mysql;
+SET SESSION debug= '+d,skip_dd_table_access_check';
 #
 # Subset of definitions from tables, not including
 # timestamps, partitioning, view definitions and
@@ -446,3 +447,4 @@ index_id	ordinal_position	column_id	length	order	hidden
 81	1	281	8	ASC	0
 82	1	282	192	ASC	0
 83	1	283	8	ASC	0
+SET SESSION debug= '-d,skip_dd_table_access_check';