MDEV-15888 Implement FLUSH TABLES tbl_name [, tbl_name] ... WITH READ LOCK for views.bb-10.6-mdev15888-hf

Kind of 'naive' solution that surprisingly worked so trying to
understand why.

6 files changed, 18 insertions, 16 deletions

diff --git a/mysql-test/main/flush-innodb.result b/mysql-test/main/flush-innodb.result
index 21e5bda7785..2c886e4f9fc 100644
--- a/mysql-test/main/flush-innodb.result
+++ b/mysql-test/main/flush-innodb.result
@@ -60,7 +60,7 @@ DROP TABLE export;
 CREATE VIEW v1 AS SELECT 1;
 CREATE TEMPORARY TABLE t1 (a INT);
 FLUSH TABLES v1 FOR EXPORT;
-ERROR HY000: 'test.v1' is not of type 'BASE TABLE'
+UNLOCK TABLES;
 FLUSH TABLES t1 FOR EXPORT;
 ERROR 42S02: Table 'test.t1' doesn't exist
 FLUSH TABLES non_existent FOR EXPORT;
diff --git a/mysql-test/main/flush-innodb.test b/mysql-test/main/flush-innodb.test
index bf7b79bb5a3..309ec5de014 100644
--- a/mysql-test/main/flush-innodb.test
+++ b/mysql-test/main/flush-innodb.test
@@ -93,8 +93,8 @@ DROP TABLE export;
 CREATE VIEW v1 AS SELECT 1;
 CREATE TEMPORARY TABLE t1 (a INT);
 
---error ER_WRONG_OBJECT
 FLUSH TABLES v1 FOR EXPORT;
+UNLOCK TABLES;
 --error ER_NO_SUCH_TABLE
 FLUSH TABLES t1 FOR EXPORT;
 --error ER_NO_SUCH_TABLE
diff --git a/mysql-test/main/flush.result b/mysql-test/main/flush.result
index 39e0b9432fe..577d6eee401 100644
--- a/mysql-test/main/flush.result
+++ b/mysql-test/main/flush.result
@@ -295,16 +295,16 @@ create view v1 as select 1;
 create view v2 as select * from t1;
 create view v3 as select * from v2;
 flush table v1, v2, v3 with read lock;
-ERROR HY000: 'test.v1' is not of type 'BASE TABLE'
+unlock tables;
 flush table v1 with read lock;
-ERROR HY000: 'test.v1' is not of type 'BASE TABLE'
+unlock tables;
 flush table v2 with read lock;
-ERROR HY000: 'test.v2' is not of type 'BASE TABLE'
+unlock tables;
 flush table v3 with read lock;
-ERROR HY000: 'test.v3' is not of type 'BASE TABLE'
+unlock tables;
 create temporary table v1 (a int);
 flush table v1 with read lock;
-ERROR HY000: 'test.v1' is not of type 'BASE TABLE'
+unlock tables;
 drop view v1;
 create table v1 (a int);
 flush table v1 with read lock;
diff --git a/mysql-test/main/flush.test b/mysql-test/main/flush.test
index 6d76196bf54..d3eaa3e413c 100644
--- a/mysql-test/main/flush.test
+++ b/mysql-test/main/flush.test
@@ -377,17 +377,17 @@ create view v1 as select 1;
 create view v2 as select * from t1;
 create view v3 as select * from v2;
 
---error ER_WRONG_OBJECT
 flush table v1, v2, v3 with read lock;
---error ER_WRONG_OBJECT
+unlock tables;
 flush table v1 with read lock;
---error ER_WRONG_OBJECT
+unlock tables;
 flush table v2 with read lock;
---error ER_WRONG_OBJECT
+unlock tables;
 flush table v3 with read lock;
+unlock tables;
 create temporary table v1 (a int);
---error ER_WRONG_OBJECT
 flush table v1 with read lock;
+unlock tables;
 drop view v1;
 create table v1 (a int);
 flush table v1 with read lock;
diff --git a/sql/sql_reload.cc b/sql/sql_reload.cc
index 8f87d633d19..c146b7693c1 100644
--- a/sql/sql_reload.cc
+++ b/sql/sql_reload.cc
@@ -543,6 +543,7 @@ bool flush_tables_with_read_lock(THD *thd, TABLE_LIST *all_tables)
 
   if (thd->lex->type & REFRESH_READ_LOCK)
   {
+#ifdef MDEV15887
     /*
       Acquire SNW locks on tables to be flushed. Don't acquire global
       IX and database-scope IX locks on the tables as this will make
@@ -559,6 +560,7 @@ bool flush_tables_with_read_lock(THD *thd, TABLE_LIST *all_tables)
     for (auto table_list= all_tables; table_list;
          table_list= table_list->next_global)
       table_list->mdl_request.ticket= NULL;
+#endif /*MDEV15887*/
   }
 
   thd->variables.option_bits|= OPTION_TABLE_LOCK;
@@ -584,7 +586,8 @@ bool flush_tables_with_read_lock(THD *thd, TABLE_LIST *all_tables)
     for (TABLE_LIST *table_list= all_tables; table_list;
          table_list= table_list->next_global)
     {
-      if (!(table_list->table->file->ha_table_flags() & HA_CAN_EXPORT))
+      if (!(table_list->is_view() ||
+            table_list->table->file->ha_table_flags() & HA_CAN_EXPORT))
       {
         my_error(ER_ILLEGAL_HA, MYF(0),table_list->table->file->table_type(),
                  table_list->db.str, table_list->table_name.str);
@@ -598,7 +601,8 @@ bool flush_tables_with_read_lock(THD *thd, TABLE_LIST *all_tables)
     for (auto table_list= all_tables; table_list;
          table_list= table_list->next_global)
     {
-      if (table_list->table->file->extra(HA_EXTRA_FLUSH))
+      if (!table_list->is_view() &&
+          table_list->table->file->extra(HA_EXTRA_FLUSH))
         goto error_reset_bits;
     }
   }
diff --git a/sql/sql_yacc.yy b/sql/sql_yacc.yy
index 5aeb14535e3..dbc1d3c6a3f 100644
--- a/sql/sql_yacc.yy
+++ b/sql/sql_yacc.yy
@@ -14082,8 +14082,6 @@ opt_flush_lock:
           for (; tables; tables= tables->next_global)
           {
             tables->mdl_request.set_type(MDL_SHARED_NO_WRITE);
-            /* Don't try to flush views. */
-            tables->required_type= TABLE_TYPE_NORMAL;
             /* Ignore temporary tables. */
             tables->open_type= OT_BASE_ONLY;
           }