remove dd_frm_type(), dd_frm_storage_engine(), dd_check_storage_engine_flag()

from everywhere - now RENAME, SHOW FULL TABLES, and TRUNCATE work with discovery.
improve error messages in truncate

mysql-test/r/mdl_sync.result

@@ -2850,7 +2850,7 @@ SET DEBUG_SYNC= 'now SIGNAL blocked';
 # Reaping: DROP DATABASE db1
 # Connection con2
 # Reaping: RENAME TABLE db1.t1 TO test.t1
-Got one of the listed errors
+ERROR 42S02: Table 'db1.t1' doesn't exist
 # Connection default
 CREATE DATABASE db1;
 CREATE TABLE test.t2 (a INT);

mysql-test/r/ps_1general.result

@@ -533,7 +533,7 @@ drop table t2;
 prepare stmt1 from ' rename table t5 to t6, t7 to t8 ' ;
 create table t5 (a int) ;
 execute stmt1 ;
-ERROR HY000: Can't find file: './test/t7' (errno: 2 "No such file or directory")
+ERROR 42S02: Table 'test.t7' doesn't exist
 create table t7 (a int) ;
 execute stmt1 ;
 execute stmt1 ;

mysql-test/r/rename.result

@@ -14,20 +14,20 @@ select * from t1;
 1	table 1
 1	table 1
 rename table t1 to t2;
-Got one of the listed errors
+ERROR 42S01: Table 't2' already exists
 rename table t1 to t1;
-Got one of the listed errors
+ERROR 42S01: Table 't1' already exists
 rename table t3 to t4, t2 to t3, t1 to t2, t4 to t2;
-Got one of the listed errors
+ERROR 42S01: Table 't2' already exists
 show tables like "t_";
 Tables_in_test (t_)
 t1
 t2
 t3
 rename table t3 to t1, t2 to t3, t1 to t2, t4 to t1;
-Got one of the listed errors
+ERROR 42S01: Table 't1' already exists
 rename table t3 to t4, t5 to t3, t1 to t2, t4 to t1;
-Got one of the listed errors
+ERROR 42S02: Table 'test.t5' doesn't exist
 select * from t1;
 1	table 1
 1	table 1

mysql-test/r/truncate_badse.result

@@ -0,0 +1,13 @@
+install plugin example soname 'ha_example';
+create table t1 (a int) engine=example;
+select 1;
+1
+1
+uninstall plugin example;
+flush tables;
+select count(*) from information_schema.plugins where plugin_name='example';
+count(*)
+0
+truncate table t1;
+ERROR 42000: Unknown storage engine 'EXAMPLE'
+drop table t1;

mysql-test/suite/archive/archive.result

@@ -12749,16 +12749,6 @@ SELECT * FROM t1;
 col1	col2
 DROP TABLE t1;
 #
-# BUG#48757 - missing .ARZ file causes server crash
-#
-CREATE TABLE t1(a INT) ENGINE=ARCHIVE;
-FLUSH TABLE t1;
-SELECT * FROM t1;
-ERROR HY000: Can't find file: './test/t1.ARZ' (errno: 2 "No such file or directory")
-DROP TABLE t1;
-Warnings:
-Warning	2	Can't find file: './test/t1.ARZ' (errno: 2 "No such file or directory")
-#
 # Ensure that TRUNCATE fails for non-empty archive tables.
 #
 CREATE TABLE t1 (a INT) ENGINE=ARCHIVE;

mysql-test/suite/archive/archive.test

@@ -1668,16 +1668,6 @@ SELECT * FROM t1;
 DROP TABLE t1;
 remove_file $MYSQLD_DATADIR/test/t1.ARM;
 
---echo #
---echo # BUG#48757 - missing .ARZ file causes server crash
---echo #
-CREATE TABLE t1(a INT) ENGINE=ARCHIVE;
-FLUSH TABLE t1;
---remove_file $MYSQLD_DATADIR/test/t1.ARZ
---error ER_FILE_NOT_FOUND
-SELECT * FROM t1;
-DROP TABLE t1;
-
 --echo #
 --echo # Ensure that TRUNCATE fails for non-empty archive tables.
 --echo #

mysql-test/suite/archive/discover.result

@@ -18,19 +18,50 @@ a
 1
 2
 #
-# list tables
+# show tables
 #
-create table t0 (a int) engine=archive;
+create table t2 (a int) engine=archive;
 flush tables;
 show tables;
 Tables_in_test
-t0
 t1
+t2
 select * from t1;
 a
 1
 2
 #
+# show full tables
+#
+flush tables;
+show full tables;
+Tables_in_test	Table_type
+t1	BASE TABLE
+t2	BASE TABLE
+select * from t1;
+a
+1
+2
+#
+# discover on truncate
+#
+flush tables;
+truncate table t1;
+ERROR HY000: Table storage engine for 't1' doesn't have this option
+show tables;
+Tables_in_test
+t1
+t2
+#
+# discover on rename
+#
+flush tables;
+rename table t2 to t0;
+show tables;
+Tables_in_test
+t0
+t1
+#
 # discover on drop
 #
 flush tables;

mysql-test/suite/archive/discover.test

@@ -15,14 +15,39 @@ insert t1 values (2);
 select * from t1;
 
 --echo #
---echo # list tables
+--echo # show tables
 --echo #
-create table t0 (a int) engine=archive;
+create table t2 (a int) engine=archive;
 remove_file $mysqld_datadir/test/t1.frm;
 flush tables;
 show tables;
 select * from t1;
 
+--echo #
+--echo # show full tables
+--echo #
+remove_file $mysqld_datadir/test/t1.frm;
+flush tables;
+show full tables;
+select * from t1;
+
+--echo #
+--echo # discover on truncate
+--echo #
+remove_file $mysqld_datadir/test/t1.frm;
+flush tables;
+--error ER_ILLEGAL_HA
+truncate table t1;
+show tables;
+
+--echo #
+--echo # discover on rename
+--echo #
+remove_file $mysqld_datadir/test/t2.frm;
+flush tables;
+rename table t2 to t0;
+show tables;
+
 --echo #
 --echo # discover on drop
 --echo #

mysql-test/t/mdl_sync.test

@@ -4382,7 +4382,7 @@ connection default;
 --echo # Connection con2
 connection con2;
 --echo # Reaping: RENAME TABLE db1.t1 TO test.t1
---error ER_FILE_NOT_FOUND, ER_FILE_NOT_FOUND
+--error ER_NO_SUCH_TABLE
 --reap
 
 --echo # Connection default

mysql-test/t/myisam-system.test

@@ -9,16 +9,21 @@ drop table if exists t1,t2;
 create table t1 (a int) engine=myisam;
 let $MYSQLD_DATADIR= `select @@datadir`;
 --remove_file $MYSQLD_DATADIR/test/t1.MYI
+--replace_result $MYSQLD_DATADIR ./
 drop table if exists t1;
 create table t1 (a int) engine=myisam;
 --remove_file $MYSQLD_DATADIR/test/t1.MYI
+--replace_result $MYSQLD_DATADIR ./
 --error ER_FILE_NOT_FOUND
 select * from t1;
+--replace_result $MYSQLD_DATADIR ./
 drop table t1;
 create table t1 (a int) engine=myisam;
 --remove_file $MYSQLD_DATADIR/test/t1.MYD
+--replace_result $MYSQLD_DATADIR ./
 --error 29
 select * from t1;
+--replace_result $MYSQLD_DATADIR ./
 drop table t1;
 --error ER_BAD_TABLE_ERROR
 drop table t1;

mysql-test/t/ps_1general.test

@@ -582,10 +582,7 @@ drop table t2;
 # cases derived from client_test.c: test_rename()
 prepare stmt1 from ' rename table t5 to t6, t7 to t8 ' ;
 create table t5 (a int) ;
-# rename must fail, t7 does not exist
+--error ER_NO_SUCH_TABLE
-# Clean up the filename here because embedded server reports whole path
---replace_result $MYSQLTEST_VARDIR . mysqld.1/data/ '' t7.frm t7
---error ER_FILE_NOT_FOUND
 execute stmt1 ;
 create table t7 (a int) ;
 # rename, t5 -> t6 and t7 -> t8

mysql-test/t/rename.test

@@ -21,16 +21,16 @@ rename table t3 to t4, t2 to t3, t1 to t2, t4 to t1;
 select * from t1;
 
 # The following should give errors
---error ER_TABLE_EXISTS_ERROR,ER_TABLE_EXISTS_ERROR
+--error ER_TABLE_EXISTS_ERROR
 rename table t1 to t2;
---error ER_TABLE_EXISTS_ERROR,ER_TABLE_EXISTS_ERROR
+--error ER_TABLE_EXISTS_ERROR
 rename table t1 to t1;
---error ER_TABLE_EXISTS_ERROR,ER_TABLE_EXISTS_ERROR
+--error ER_TABLE_EXISTS_ERROR
 rename table t3 to t4, t2 to t3, t1 to t2, t4 to t2;
 show tables like "t_";
---error ER_TABLE_EXISTS_ERROR,ER_TABLE_EXISTS_ERROR
+--error ER_TABLE_EXISTS_ERROR
 rename table t3 to t1, t2 to t3, t1 to t2, t4 to t1;
---error ER_FILE_NOT_FOUND,ER_FILE_NOT_FOUND
+--error ER_NO_SUCH_TABLE
 rename table t3 to t4, t5 to t3, t1 to t2, t4 to t1;
 
 select * from t1;

mysql-test/t/truncate_badse.test

@@ -0,0 +1,15 @@
+#
+# test what TRUNCATE TABLE does, if the table was created in
+# now-unknown storage engine.
+#
+--source include/have_example_plugin.inc
+install plugin example soname 'ha_example';
+create table t1 (a int) engine=example;
+select 1;
+uninstall plugin example;
+flush tables;
+select count(*) from information_schema.plugins where plugin_name='example';
+--error ER_UNKNOWN_STORAGE_ENGINE
+truncate table t1;
+drop table t1;
+

sql/datadict.cc

@@ -70,88 +70,6 @@ frm_type_enum dd_frm_type(THD *thd, char *path, enum legacy_db_type *dbt)
 }
 
 
-/**
-  Given a table name, check type of .frm and legacy table type.
-
-  @param[in]   thd          The current session.
-  @param[in]   db           Table schema.
-  @param[in]   table_name   Table database.
-  @param[out]  table_type   handlerton of the table if FRMTYPE_TABLE,
-                            otherwise undefined.
-
-  @return FALSE if FRMTYPE_TABLE and storage engine found. TRUE otherwise.
-*/
-
-bool dd_frm_storage_engine(THD *thd, const char *db, const char *table_name,
-                           handlerton **table_type)
-{
-  char path[FN_REFLEN + 1];
-  enum legacy_db_type db_type;
-  LEX_STRING db_name = {(char *) db, strlen(db)};
-
-  /* There should be at least some lock on the table.  */
-  DBUG_ASSERT(thd->mdl_context.is_lock_owner(MDL_key::TABLE, db,
-                                             table_name, MDL_SHARED));
-
-  if (check_db_name(&db_name))
-  {
-    my_error(ER_WRONG_DB_NAME, MYF(0), db_name.str);
-    return TRUE;
-  }
-
-  if (check_table_name(table_name, strlen(table_name), FALSE))
-  {
-    my_error(ER_WRONG_TABLE_NAME, MYF(0), table_name);
-    return TRUE;
-  }
-
-  (void) build_table_filename(path, sizeof(path) - 1, db,
-                              table_name, reg_ext, 0);
-
-  dd_frm_type(thd, path, &db_type);
-
-  /* Type is unknown if the object is not found or is not a table. */
-  if (db_type == DB_TYPE_UNKNOWN ||
-      !(*table_type= ha_resolve_by_legacy_type(thd, db_type)))
-  {
-    my_error(ER_NO_SUCH_TABLE, MYF(0), db, table_name);
-    return TRUE;
-  }
-
-  return FALSE;
-}
-
-
-/**
-  Given a table name, check if the storage engine for the
-  table referred by this name supports an option 'flag'.
-  Return an error if the table does not exist or is not a
-  base table.
-
-  @pre Any metadata lock on the table.
-
-  @param[in]    thd         The current session.
-  @param[in]    db          Table schema.
-  @param[in]    table_name  Table database.
-  @param[in]    flag        The option to check.
-  @param[out]   yes_no      The result. Undefined if error.
-*/
-
-bool dd_check_storage_engine_flag(THD *thd,
-                                  const char *db, const char *table_name,
-                                  uint32 flag, bool *yes_no)
-{
-  handlerton *table_type;
-
-  if (dd_frm_storage_engine(thd, db, table_name, &table_type))
-    return TRUE;
-
-  *yes_no= ha_check_storage_engine_flag(table_type, flag);
-
-  return FALSE;
-}
-
-
 /*
   Regenerate a metadata locked table.
 

sql/datadict.h

@@ -28,14 +28,21 @@ enum frm_type_enum
   FRMTYPE_VIEW
 };
 
+/*
+  Take extra care when using dd_frm_type() - it only checks the .frm file,
+  and it won't work for any engine that supports discovery.
+
+  Prefer to use ha_table_exists() instead.
+  To check whether it's an frm of a view, use dd_frm_is_view().
+*/
 frm_type_enum dd_frm_type(THD *thd, char *path, enum legacy_db_type *dbt);
 
-bool dd_frm_storage_engine(THD *thd, const char *db, const char *table_name,
+static inline bool dd_frm_is_view(THD *thd, char *path)
-                           handlerton **table_type);
+{
-bool dd_check_storage_engine_flag(THD *thd,
+  enum legacy_db_type not_used;
-                                  const char *db, const char *table_name,
+  return dd_frm_type(thd, path, &not_used) == FRMTYPE_VIEW;
-                                  uint32 flag,
+}
-                                  bool *yes_no);
+
 bool dd_recreate_table(THD *thd, const char *db, const char *table_name,
                        const char *path = NULL);
 

sql/handler.cc

@@ -386,7 +386,6 @@ static int ha_finish_errors(void)
 static volatile int32 need_full_discover_for_existence= 0;
 static volatile int32 engines_with_discover_table_names= 0;
 
-
 static int full_discover_for_existence(handlerton *, const char *, const char *)
 { return 1; }
 
@@ -4373,8 +4372,7 @@ public:
     *cond_hdl= NULL;
     if (sql_errno == ER_NO_SUCH_TABLE ||
         sql_errno == ER_NO_SUCH_TABLE_IN_ENGINE ||
-        sql_errno == ER_WRONG_OBJECT ||
+        sql_errno == ER_WRONG_OBJECT)
-        sql_errno == ER_OPTION_PREVENTS_STATEMENT) // partition_disabled.test
     {
       m_handled_errors++;
       return TRUE;

sql/sql_base.cc

@@ -55,7 +55,7 @@
 #include <hash.h>
 #include "rpl_filter.h"
 #include "sql_table.h"                          // build_table_filename
-#include "datadict.h"   // dd_frm_type()
+#include "datadict.h"   // dd_frm_is_view()
 #include "sql_hset.h"   // Hash_set
 #ifdef  __WIN__
 #include <io.h>
@@ -2774,7 +2774,6 @@ bool open_table(THD *thd, TABLE_LIST *table_list, MEM_ROOT *mem_root,
                                        MDL_SHARED))
     {
       char path[FN_REFLEN + 1];
-      enum legacy_db_type not_used;
       build_table_filename(path, sizeof(path) - 1,
                            table_list->db, table_list->table_name, reg_ext, 0);
       /*
@@ -2784,7 +2783,7 @@ bool open_table(THD *thd, TABLE_LIST *table_list, MEM_ROOT *mem_root,
         during prelocking process (in this case in theory we still
         should hold shared metadata lock on it).
       */
-      if (dd_frm_type(thd, path, &not_used) == FRMTYPE_VIEW)
+      if (dd_frm_is_view(thd, path))
       {
         if (!tdc_open_view(thd, table_list, alias, key, key_length,
                            mem_root, 0))

sql/sql_rename.cc

@@ -29,7 +29,6 @@
 #include "sql_base.h"   // tdc_remove_table, lock_table_names,
 #include "sql_handler.h"                        // mysql_ha_rm_tables
 #include "sql_statistics.h" 
-#include "datadict.h"
 
 static TABLE_LIST *rename_tables(THD *thd, TABLE_LIST *table_list,
 				 bool skip_error);
@@ -241,11 +240,9 @@ do_rename(THD *thd, TABLE_LIST *ren_table, char *new_db, char *new_table_name,
           char *new_table_alias, bool skip_error)
 {
   int rc= 1;
-  char name[FN_REFLEN + 1];
+  handlerton *hton;
+  bool new_exists, old_exists;
   const char *new_alias, *old_alias;
-  frm_type_enum frm_type;
-  enum legacy_db_type table_type;
-
   DBUG_ENTER("do_rename");
 
   if (lower_case_table_names == 2)
@@ -260,53 +257,48 @@ do_rename(THD *thd, TABLE_LIST *ren_table, char *new_db, char *new_table_name,
   }
   DBUG_ASSERT(new_alias);
 
-  build_table_filename(name, sizeof(name) - 1,
+  new_exists= ha_table_exists(thd, new_db, new_alias);
-                       new_db, new_alias, reg_ext, 0);
+
-  if (!access(name,F_OK))
+  if (new_exists)
   {
     my_error(ER_TABLE_EXISTS_ERROR, MYF(0), new_alias);
-    DBUG_RETURN(1);			// This can't be skipped
+    DBUG_RETURN(1);                     // This can't be skipped
   }
-  build_table_filename(name, sizeof(name) - 1,
-                       ren_table->db, old_alias, reg_ext, 0);
 
-  frm_type= dd_frm_type(thd, name, &table_type);
+  old_exists= ha_table_exists(thd, ren_table->db, old_alias, &hton);
-  switch (frm_type)
+
+  if (old_exists)
   {
-    case FRMTYPE_TABLE:
+    if (hton != view_pseudo_hton)
+    {
+      if (!(rc= mysql_rename_table(hton, ren_table->db, old_alias,
+                                   new_db, new_alias, 0)))
       {
-        if (!(rc= mysql_rename_table(ha_resolve_by_legacy_type(thd,
+        LEX_STRING db_name= { ren_table->db, ren_table->db_length };
-                                                               table_type), 
+        LEX_STRING table_name= { ren_table->table_name,
-                                     ren_table->db, old_alias,
+                                 ren_table->table_name_length };
-                                     new_db, new_alias, 0)))
+        LEX_STRING new_table= { (char *) new_alias, strlen(new_alias) };
+        (void) rename_table_in_stat_tables(thd, &db_name, &table_name,
+                                           &db_name, &new_table);
+        if ((rc= Table_triggers_list::change_table_name(thd, ren_table->db,
+                                                        old_alias,
+                                                        ren_table->table_name,
+                                                        new_db,
+                                                        new_alias)))
         {
-          LEX_STRING db_name= { ren_table->db, ren_table->db_length };
+          /*
-          LEX_STRING table_name= { ren_table->table_name,
+            We've succeeded in renaming table's .frm and in updating
-                                   ren_table->table_name_length };
+            corresponding handler data, but have failed to update table's
-          LEX_STRING new_table= { (char *) new_alias, strlen(new_alias) };
+            triggers appropriately. So let us revert operations on .frm
-          (void) rename_table_in_stat_tables(thd, &db_name, &table_name,
+            and handler's data and report about failure to rename table.
-                                             &db_name, &new_table);
+          */
-          if ((rc= Table_triggers_list::change_table_name(thd, ren_table->db,
+          (void) mysql_rename_table(hton, new_db, new_alias,
-                                                          old_alias,
+                                    ren_table->db, old_alias, 0);
-                                                          ren_table->table_name,
-                                                          new_db,
-                                                          new_alias)))
-          {
-            /*
-              We've succeeded in renaming table's .frm and in updating
-              corresponding handler data, but have failed to update table's
-              triggers appropriately. So let us revert operations on .frm
-              and handler's data and report about failure to rename table.
-            */
-            (void) mysql_rename_table(ha_resolve_by_legacy_type(thd,
-                                                                table_type),
-                                      new_db, new_alias,
-                                      ren_table->db, old_alias, 0);
-          }
         }
       }
-      break;
+    }
-    case FRMTYPE_VIEW:
+    else
+    {
       /* 
          change of schema is not allowed
          except of ALTER ...UPGRADE DATA DIRECTORY NAME command
@@ -314,22 +306,19 @@ do_rename(THD *thd, TABLE_LIST *ren_table, char *new_db, char *new_table_name,
       */
       if (thd->lex->sql_command != SQLCOM_ALTER_DB_UPGRADE &&
           strcmp(ren_table->db, new_db))
-        my_error(ER_FORBID_SCHEMA_CHANGE, MYF(0), ren_table->db, 
+        my_error(ER_FORBID_SCHEMA_CHANGE, MYF(0), ren_table->db, new_db);
-                 new_db);
       else
         rc= mysql_rename_view(thd, new_db, new_alias, ren_table);
-      break;
+    }
-    default:
+  }
-      DBUG_ASSERT(0); // should never happen
+  else
-    case FRMTYPE_ERROR:
+  {
-      my_error(ER_FILE_NOT_FOUND, MYF(0), name, my_errno);
+    my_error(ER_NO_SUCH_TABLE, MYF(0), ren_table->db, old_alias);
-      break;
   }
   if (rc && !skip_error)
     DBUG_RETURN(1);
 
   DBUG_RETURN(0);
-
 }
 /*
   Rename all tables in list; Return pointer to wrong entry if something goes

sql/sql_show.cc

@@ -57,7 +57,6 @@
 #include <my_dir.h>
 #include "lock.h"                           // MYSQL_OPEN_IGNORE_FLUSH
 #include "debug_sync.h"
-#include "datadict.h"   // dd_frm_type()
 #include "keycaches.h"
 
 #ifdef WITH_PARTITION_STORAGE_ENGINE
@@ -4072,26 +4071,18 @@ static int fill_schema_table_names(THD *thd, TABLE_LIST *tables,
   }
   else if (tables->table_open_method != SKIP_OPEN_TABLE)
   {
-    enum legacy_db_type not_used;
+    CHARSET_INFO *cs= system_charset_info;
-    char path[FN_REFLEN + 1];
+    handlerton *hton;
-    (void) build_table_filename(path, sizeof(path) - 1, db_name->str, 
+    if (ha_table_exists(thd, db_name->str, table_name->str, &hton))
-                                table_name->str, reg_ext, 0);
+    {
-    switch (dd_frm_type(thd, path, &not_used)) {
+      if (hton == view_pseudo_hton)
-    case FRMTYPE_ERROR:
+        table->field[3]->store(STRING_WITH_LEN("VIEW"), cs);
-      table->field[3]->store(STRING_WITH_LEN("ERROR"),
+      else
-                             system_charset_info);
+        table->field[3]->store(STRING_WITH_LEN("BASE TABLE"), cs);
-      break;
-    case FRMTYPE_TABLE:
-      table->field[3]->store(STRING_WITH_LEN("BASE TABLE"),
-                             system_charset_info);
-      break;
-    case FRMTYPE_VIEW:
-      table->field[3]->store(STRING_WITH_LEN("VIEW"),
-                             system_charset_info);
-      break;
-    default:
-      DBUG_ASSERT(0);
     }
+    else
+      table->field[3]->store(STRING_WITH_LEN("ERROR"), cs);
+
     if (thd->is_error() && thd->stmt_da->sql_errno() == ER_NO_SUCH_TABLE)
     {
       thd->clear_error();

sql/sql_table.cc

@@ -4637,9 +4637,13 @@ mysql_rename_table(handlerton *base, const char *old_db,
     if (!(flags & NO_FRM_RENAME) && rename_file_ext(from,to,reg_ext))
     {
       error=my_errno;
-      /* Restore old file name */
       if (file)
-        file->ha_rename_table(to_base, from_base);
+      {
+        if (error == ENOENT)
+          error= 0; // this is ok if file->ha_rename_table() succeeded
+        else
+          file->ha_rename_table(to_base, from_base); // Restore old file name
+      }
     }
   }
   delete file;

sql/sql_truncate.cc

@@ -341,9 +341,27 @@ bool Truncate_statement::lock_table(THD *thd, TABLE_LIST *table_ref,
                          MYSQL_OPEN_SKIP_TEMPORARY))
       DBUG_RETURN(TRUE);
 
-    if (dd_check_storage_engine_flag(thd, table_ref->db, table_ref->table_name,
+    handlerton *hton;
-                                     HTON_CAN_RECREATE, hton_can_recreate))
+    if (!ha_table_exists(thd, table_ref->db, table_ref->table_name, &hton) ||
+        hton == view_pseudo_hton)
+    {
+      my_error(ER_NO_SUCH_TABLE, MYF(0), table_ref->db, table_ref->table_name);
       DBUG_RETURN(TRUE);
+    }
+
+    if (!hton)
+    {
+      /*
+        The table exists, but its storage engine is unknown, perhaps not
+        loaded at the moment. We need to open and parse the frm to know the
+        storage engine in question, so let's proceed with the truncation and
+        try to open the table. This will produce the correct error message
+        about unknown engine.
+      */
+      *hton_can_recreate= false;
+    }
+    else
+      *hton_can_recreate= hton->flags & HTON_CAN_RECREATE;
   }
 
   /*

sql/sql_view.cc

@@ -33,7 +33,7 @@
 #include "sp_head.h"
 #include "sp.h"
 #include "sp_cache.h"
-#include "datadict.h"   // dd_frm_type()
+#include "datadict.h"   // dd_frm_is_view()
 
 #define MD5_BUFF_LENGTH 33
 
@@ -1642,7 +1642,6 @@ bool mysql_drop_view(THD *thd, TABLE_LIST *views, enum_drop_mode drop_mode)
   String non_existant_views;
   char *wrong_object_db= NULL, *wrong_object_name= NULL;
   bool error= FALSE;
-  enum legacy_db_type not_used;
   bool some_views_deleted= FALSE;
   bool something_wrong= FALSE;
   DBUG_ENTER("mysql_drop_view");
@@ -1665,12 +1664,11 @@ bool mysql_drop_view(THD *thd, TABLE_LIST *views, enum_drop_mode drop_mode)
 
   for (view= views; view; view= view->next_local)
   {
-    frm_type_enum type= FRMTYPE_ERROR;
+    bool not_exist;
     build_table_filename(path, sizeof(path) - 1,
                          view->db, view->table_name, reg_ext, 0);
 
-    if (access(path, F_OK) || 
+    if ((not_exist= my_access(path, F_OK)) || !dd_frm_is_view(thd, path))
-        FRMTYPE_VIEW != (type= dd_frm_type(thd, path, &not_used)))
     {
       char name[FN_REFLEN];
       my_snprintf(name, sizeof(name), "%s.%s", view->db, view->table_name);
@@ -1681,7 +1679,13 @@ bool mysql_drop_view(THD *thd, TABLE_LIST *views, enum_drop_mode drop_mode)
 			    name);
 	continue;
       }
-      if (type == FRMTYPE_TABLE)
+      if (not_exist)
+      {
+        if (non_existant_views.length())
+          non_existant_views.append(',');
+        non_existant_views.append(String(view->table_name,system_charset_info));
+      }
+      else
       {
         if (!wrong_object_name)
         {
@@ -1689,12 +1693,6 @@ bool mysql_drop_view(THD *thd, TABLE_LIST *views, enum_drop_mode drop_mode)
           wrong_object_name= view->table_name;
         }
       }
-      else
-      {
-        if (non_existant_views.length())
-          non_existant_views.append(',');
-        non_existant_views.append(String(view->table_name,system_charset_info));
-      }
       continue;
     }
     if (mysql_file_delete(key_file_frm, path, MYF(MY_WME)))

sql/table.cc

@@ -572,24 +572,6 @@ inline bool is_system_table_name(const char *name, uint length)
 }
 
 
-/*
-  We don't try to open 5.0 unencoded name, if
-  - non-encoded name contains '@' signs, 
-    because '@' can be misinterpreted.
-    It is not clear if '@' is escape character in 5.1,
-    or a normal character in 5.0.
-    
-  - non-encoded db or table name contain "#mysql50#" prefix.
-    This kind of tables must have been opened only by the
-    mysql_file_open() above.
-*/
-static bool has_disabled_path_chars(const char *str)
-{
-  return strpbrk(str, "/\\~@.") != 0 ||
-         strncmp(str, STRING_WITH_LEN(MYSQL50_TABLE_NAME_PREFIX)) == 0;
-}
-
-
 /*
   Read table definition from a binary / text based .frm file
   
@@ -3176,7 +3158,7 @@ rename_file_ext(const char * from,const char * to,const char * ext)
   char from_b[FN_REFLEN],to_b[FN_REFLEN];
   (void) strxmov(from_b,from,ext,NullS);
   (void) strxmov(to_b,to,ext,NullS);
-  return (mysql_file_rename(key_file_frm, from_b, to_b, MYF(MY_WME)));
+  return (mysql_file_rename(key_file_frm, from_b, to_b, MYF(0)));
 }