Added IF EXISTS to RENAME TABLE and ALTER TABLE

mysql-test/main/alter_table.result

@@ -3244,3 +3244,22 @@ drop table t1;
 #
 # End of 10.5 tests
 #
+#
+# ALTER TABLE IF EXISTS
+#
+create table t1 (a int);
+alter table if exists t1 add column b int;
+alter table if exists t2 add column c int;
+Warnings:
+Error	1146	Table 'test.t2' doesn't exist
+alter table if exists t9 rename t1;
+Warnings:
+Error	1146	Table 'test.t9' doesn't exist
+alter table if exists t1 rename t2;
+show create table t2;
+Table	Create Table
+t2	CREATE TABLE `t2` (
+  `a` int(11) DEFAULT NULL,
+  `b` int(11) DEFAULT NULL
+) ENGINE=MyISAM DEFAULT CHARSET=latin1
+drop table t2;

mysql-test/main/alter_table.test

@@ -2456,3 +2456,15 @@ drop table t1;
 --echo #
 --echo # End of 10.5 tests
 --echo #
+
+--echo #
+--echo # ALTER TABLE IF EXISTS
+--echo #
+
+create table t1 (a int);
+alter table if exists t1 add column b int;
+alter table if exists t2 add column c int;
+alter table if exists t9 rename t1;
+alter table if exists t1 rename t2;
+show create table t2;
+drop table t2;

mysql-test/main/ps_1general.result

@@ -528,9 +528,11 @@ drop table if exists new_t2;
 prepare stmt3 from ' rename table t2 to new_t2 ';
 execute stmt3;
 execute stmt3;
+ERROR 42S02: Table 'test.t2' doesn't exist
+create table t2 like new_t2;
+execute stmt3;
 ERROR 42S01: Table 'new_t2' already exists
-rename table new_t2 to t2;
+drop table new_t2,t2;
-drop table t2;
 prepare stmt1 from ' rename table t5 to t6, t7 to t8 ' ;
 create table t5 (a int) ;
 execute stmt1 ;
@@ -538,7 +540,7 @@ ERROR 42S02: Table 'test.t7' doesn't exist
 create table t7 (a int) ;
 execute stmt1 ;
 execute stmt1 ;
-ERROR 42S01: Table 't6' already exists
+ERROR 42S02: Table 'test.t5' doesn't exist
 rename table t6 to t5, t8 to t7 ;
 execute stmt1 ;
 drop table t6, t8 ;

mysql-test/main/ps_1general.test

@@ -576,10 +576,12 @@ drop table if exists new_t2;
 --enable_warnings
 prepare stmt3 from ' rename table t2 to new_t2 ';
 execute stmt3;
+--error ER_NO_SUCH_TABLE
+execute stmt3;
+create table t2 like new_t2;
 --error ER_TABLE_EXISTS_ERROR
 execute stmt3;
-rename table new_t2 to t2;
+drop table new_t2,t2;
-drop table t2;
 ## RENAME more than on TABLE within one statement
 # cases derived from client_test.c: test_rename()
 prepare stmt1 from ' rename table t5 to t6, t7 to t8 ' ;
@@ -590,7 +592,7 @@ create table t7 (a int) ;
 # rename, t5 -> t6 and t7 -> t8
 execute stmt1 ;
 # rename must fail, t5 and t7 does not exist t6 and t8 already exist
---error ER_TABLE_EXISTS_ERROR
+--error ER_NO_SUCH_TABLE
 execute stmt1 ;
 rename table t6 to t5, t8 to t7 ;
 # rename, t5 -> t6 and t7 -> t8

mysql-test/main/rename.result

@@ -148,3 +148,28 @@ create table t1 (a int) engine=memory;
 rename table t1 to non_existent.t2;
 ERROR 42000: Unknown database 'non_existent'
 drop table t1;
+#
+# Test rename IF EXISTS
+#
+rename table if exists t1 to t2;
+Warnings:
+Note	1146	Table 'test.t1' doesn't exist
+alter table if exists t1 rename to t2;
+Warnings:
+Error	1146	Table 'test.t1' doesn't exist
+create table t2 (a int);
+alter table if exists t1 rename to t2;
+Warnings:
+Error	1146	Table 'test.t1' doesn't exist
+rename table if exists t1 to t2;
+Warnings:
+Note	1146	Table 'test.t1' doesn't exist
+create table t1 (a int);
+rename table if exists t1 to t2;
+ERROR 42S01: Table 't2' already exists
+alter table if exists t1 rename to t2;
+ERROR 42S01: Table 't2' already exists
+drop table t2;
+rename table if exists t1 to t2;
+alter table if exists t2 rename to t1;
+drop table t1;

mysql-test/main/rename.test

@@ -148,3 +148,21 @@ create table t1 (a int) engine=memory;
 --error ER_BAD_DB_ERROR
 rename table t1 to non_existent.t2;
 drop table t1;
+
+--echo #
+--echo # Test rename IF EXISTS
+--echo #
+rename table if exists t1 to t2;
+alter table if exists t1 rename to t2;
+create table t2 (a int);
+alter table if exists t1 rename to t2;
+rename table if exists t1 to t2;
+create table t1 (a int);
+--error ER_TABLE_EXISTS_ERROR
+rename table if exists t1 to t2;
+--error ER_TABLE_EXISTS_ERROR
+alter table if exists t1 rename to t2;
+drop table t2;
+rename table if exists t1 to t2;
+alter table if exists t2 rename to t1;
+drop table t1;

mysql-test/suite/engines/funcs/r/tc_rename_error.result

@@ -13,7 +13,7 @@ t1	CREATE TABLE `t1` (
 RENAME TABLE t2 TO t1;
 ERROR 42S01: Table 't1' already exists
 RENAME TABLE t3 TO t1;
-ERROR 42S01: Table 't1' already exists
+ERROR 42S02: Table 'test.t3' doesn't exist
 RENAME TABLE t3 TO doesnotexist.t1;
 ERROR 42S02: Table 'test.t3' doesn't exist
 SHOW TABLES;

mysql-test/suite/engines/funcs/t/tc_rename_error.test

@@ -7,9 +7,9 @@ SHOW TABLES;
 let $ENGINE=`select variable_value from information_schema.global_variables where variable_name='STORAGE_ENGINE'`; 
 --replace_result $ENGINE ENGINE " PAGE_CHECKSUM=0" "" " PAGE_CHECKSUM=1" ""
  SHOW CREATE TABLE t1; 
---error 1050
+--error ER_TABLE_EXISTS_ERROR
 RENAME TABLE t2 TO t1;
---error 1050
+--error ER_NO_SUCH_TABLE
 RENAME TABLE t3 TO t1;
 --error 1146
 RENAME TABLE t3 TO doesnotexist.t1;

sql/handler.cc

@@ -5624,7 +5624,8 @@ private:
         *hton will be NULL.
 */
 
-bool ha_table_exists(THD *thd, const LEX_CSTRING *db, const LEX_CSTRING *table_name,
+bool ha_table_exists(THD *thd, const LEX_CSTRING *db,
+                     const LEX_CSTRING *table_name,
                      handlerton **hton, bool *is_sequence)
 {
   handlerton *dummy;

sql/sql_alter.cc

@@ -522,7 +522,7 @@ bool Sql_cmd_alter_table::execute(THD *thd)
                             &alter_info,
                             select_lex->order_list.elements,
                             select_lex->order_list.first,
-                            lex->ignore);
+                            lex->ignore, lex->if_exists());
 
   DBUG_RETURN(result);
 #ifdef WITH_WSREP

sql/sql_db.cc

@@ -1805,7 +1805,7 @@ bool mysql_upgrade_db(THD *thd, const LEX_CSTRING *old_db)
   }
 
   if ((table_list= thd->lex->query_tables) &&
-      (error= mysql_rename_tables(thd, table_list, 1)))
+      (error= mysql_rename_tables(thd, table_list, 1, 0)))
   {
     /*
       Failed to move all tables from the old database to the new one.

sql/sql_parse.cc

@@ -4160,7 +4160,7 @@ mysql_execute_command(THD *thd)
 
     res= mysql_alter_table(thd, &first_table->db, &first_table->table_name,
                            &create_info, first_table, &alter_info,
-                           0, (ORDER*) 0, 0);
+                           0, (ORDER*) 0, 0, lex->if_exists());
     break;
   }
 #ifdef HAVE_REPLICATION
@@ -4272,7 +4272,7 @@ mysql_execute_command(THD *thd)
 
     WSREP_TO_ISOLATION_BEGIN(0, 0, first_table);
 
-    if (mysql_rename_tables(thd, first_table, 0))
+    if (mysql_rename_tables(thd, first_table, 0, lex->if_exists()))
       goto error;
     break;
   }

sql/sql_rename.cc

@@ -32,10 +32,13 @@
 #include "sql_statistics.h" 
 
 static TABLE_LIST *rename_tables(THD *thd, TABLE_LIST *table_list,
-				 bool skip_error);
+                                 bool skip_error, bool if_exits,
-static bool do_rename(THD *thd, TABLE_LIST *ren_table, const LEX_CSTRING *new_db,
+                                 bool *force_if_exists);
-                      const LEX_CSTRING *new_table_name, const LEX_CSTRING *new_table_alias,
+static bool do_rename(THD *thd, TABLE_LIST *ren_table,
-                      bool skip_error);
+                      const LEX_CSTRING *new_db,
+                      const LEX_CSTRING *new_table_name,
+                      const LEX_CSTRING *new_table_alias,
+                      bool skip_error, bool if_exists, bool *force_if_exists);
 
 static TABLE_LIST *reverse_table_list(TABLE_LIST *table_list);
 
@@ -44,10 +47,11 @@ static TABLE_LIST *reverse_table_list(TABLE_LIST *table_list);
   the new name.
 */
 
-bool mysql_rename_tables(THD *thd, TABLE_LIST *table_list, bool silent)
+bool mysql_rename_tables(THD *thd, TABLE_LIST *table_list, bool silent,
+                          bool if_exists)
 {
   bool error= 1;
-  bool binlog_error= 0;
+  bool binlog_error= 0, force_if_exists;
   TABLE_LIST *ren_table= 0;
   int to_table;
   const char *rename_log_table[2]= {NULL, NULL};
@@ -151,7 +155,8 @@ bool mysql_rename_tables(THD *thd, TABLE_LIST *table_list, bool silent)
     An exclusive lock on table names is satisfactory to ensure
     no other thread accesses this table.
   */
-  if ((ren_table=rename_tables(thd,table_list,0)))
+  if ((ren_table= rename_tables(thd, table_list, 0, if_exists,
+                                &force_if_exists)))
   {
     /* Rename didn't succeed;  rename back the tables in reverse order */
     TABLE_LIST *table;
@@ -165,7 +170,7 @@ bool mysql_rename_tables(THD *thd, TABLE_LIST *table_list, bool silent)
 	 table= table->next_local->next_local) ;
     table= table->next_local->next_local;		// Skip error table
     /* Revert to old names */
-    rename_tables(thd, table, 1);
+    rename_tables(thd, table, 1, if_exists, &force_if_exists);
 
     /* Revert the table list (for prepared statements) */
     table_list= reverse_table_list(table_list);
@@ -246,6 +251,9 @@ do_rename_temporary(THD *thd, TABLE_LIST *ren_table, TABLE_LIST *new_table,
       new_table_name    The new table/view name
       new_table_alias   The new table/view alias
       skip_error        Whether to skip error
+      if_exists         Skip error, but only if the table didn't exists
+      force_if_exists   Set to 1 if we have to log the query with 'IF EXISTS'
+                        Otherwise don't touch the value
 
   DESCRIPTION
     Rename a single table or a view.
@@ -257,13 +265,16 @@ do_rename_temporary(THD *thd, TABLE_LIST *ren_table, TABLE_LIST *new_table,
 
 static bool
 do_rename(THD *thd, TABLE_LIST *ren_table, const LEX_CSTRING *new_db,
-          const LEX_CSTRING *new_table_name, const LEX_CSTRING *new_table_alias,
+          const LEX_CSTRING *new_table_name,
-          bool skip_error)
+          const LEX_CSTRING *new_table_alias,
+          bool skip_error, bool if_exists, bool *force_if_exists)
 {
   int rc= 1;
-  handlerton *hton;
+  handlerton *hton, *new_hton;
   LEX_CSTRING old_alias, new_alias;
   DBUG_ENTER("do_rename");
+  DBUG_PRINT("enter", ("skip_error: %d  if_exists: %d", (int) skip_error,
+                       (int) if_exists));
 
   if (lower_case_table_names == 2)
   {
@@ -277,13 +288,19 @@ do_rename(THD *thd, TABLE_LIST *ren_table, const LEX_CSTRING *new_db,
   }
   DBUG_ASSERT(new_alias.str);
 
-  if (ha_table_exists(thd, new_db, &new_alias))
+  if (!ha_table_exists(thd, &ren_table->db, &old_alias, &hton) || !hton)
+  {
+    my_error(ER_NO_SUCH_TABLE, MYF((skip_error | if_exists) ? ME_NOTE : 0),
+             ren_table->db.str, old_alias.str);
+    DBUG_RETURN(skip_error || if_exists ? 0 : 1);
+  }
+
+  if (ha_table_exists(thd, new_db, &new_alias, &new_hton))
   {
     my_error(ER_TABLE_EXISTS_ERROR, MYF(0), new_alias.str);
     DBUG_RETURN(1);                     // This can't be skipped
   }
 
-  if (ha_table_exists(thd, &ren_table->db, &old_alias, &hton) && hton)
   {
     DBUG_ASSERT(!thd->locked_tables_mode);
 
@@ -335,14 +352,7 @@ do_rename(THD *thd, TABLE_LIST *ren_table, const LEX_CSTRING *new_db,
         rc= mysql_rename_view(thd, new_db, &new_alias, ren_table);
     }
   }
-  else
+  DBUG_RETURN(rc && !skip_error ? 1 : 0);
-  {
-    my_error(ER_NO_SUCH_TABLE, MYF(0), ren_table->db.str, old_alias.str);
-  }
-  if (unlikely(rc && !skip_error))
-    DBUG_RETURN(1);
-
-  DBUG_RETURN(0);
 }
 
 
@@ -359,6 +369,9 @@ do_rename(THD *thd, TABLE_LIST *ren_table, const LEX_CSTRING *new_db,
       thd               Thread handle
       table_list        List of tables to rename
       skip_error        Whether to skip errors
+      if_exists         Don't give an error if table doesn't exists
+      force_if_exists   Set to 1 if we have to log the query with 'IF EXISTS'
+                        Otherwise set it to 0
 
   DESCRIPTION
     Take a table/view name from and odd list element and rename it to a
@@ -371,12 +384,14 @@ do_rename(THD *thd, TABLE_LIST *ren_table, const LEX_CSTRING *new_db,
 */
 
 static TABLE_LIST *
-rename_tables(THD *thd, TABLE_LIST *table_list, bool skip_error)
+rename_tables(THD *thd, TABLE_LIST *table_list, bool skip_error,
+              bool if_exists, bool *force_if_exists)
 {
   TABLE_LIST *ren_table, *new_table;
-
   DBUG_ENTER("rename_tables");
 
+  *force_if_exists= 0;
+
   for (ren_table= table_list; ren_table; ren_table= new_table->next_local)
   {
     new_table= ren_table->next_local;
@@ -384,7 +399,7 @@ rename_tables(THD *thd, TABLE_LIST *table_list, bool skip_error)
     if (is_temporary_table(ren_table) ?
           do_rename_temporary(thd, ren_table, new_table, skip_error) :
           do_rename(thd, ren_table, &new_table->db, &new_table->table_name,
-                    &new_table->alias, skip_error))
+                    &new_table->alias, skip_error, if_exists, force_if_exists))
       DBUG_RETURN(ren_table);
   }
   DBUG_RETURN(0);

sql/sql_rename.h

@@ -19,6 +19,7 @@
 class THD;
 struct TABLE_LIST;
 
-bool mysql_rename_tables(THD *thd, TABLE_LIST *table_list, bool silent);
+bool mysql_rename_tables(THD *thd, TABLE_LIST *table_list, bool silent,
+                         bool if_exists);
 
 #endif /* SQL_RENAME_INCLUDED */

sql/sql_table.cc

@@ -2777,7 +2777,7 @@ bool quick_rm_table(THD *thd, handlerton *base, const LEX_CSTRING *db,
     delete file;
   }
   if (!(flags & (FRM_ONLY|NO_HA_TABLE)))
-    error|= ha_delete_table(current_thd, base, path, db, table_name, 0);
+    error|= ha_delete_table(thd, base, path, db, table_name, 0);
 
   if (likely(error == 0))
   {
@@ -4392,8 +4392,8 @@ mysql_prepare_create_table(THD *thd, HA_CREATE_INFO *create_info,
 /**
   check comment length of table, column, index and partition
 
-  If comment lenght is more than the standard length
+  If comment length is more than the standard length
-  truncate it and store the comment lenght upto the standard
+  truncate it and store the comment length upto the standard
   comment length size
 
   @param          thd             Thread handle
@@ -9467,9 +9467,40 @@ bool mysql_alter_table(THD *thd, const LEX_CSTRING *new_db,
                        HA_CREATE_INFO *create_info,
                        TABLE_LIST *table_list,
                        Alter_info *alter_info,
-                       uint order_num, ORDER *order, bool ignore)
+                       uint order_num, ORDER *order, bool ignore,
+                       bool if_exists)
 {
-  bool engine_changed;
+  bool engine_changed, error;
+  bool no_ha_table= true;  /* We have not created table in storage engine yet */
+  TABLE *table, *new_table;
+#ifdef WITH_PARTITION_STORAGE_ENGINE
+  bool partition_changed= false;
+  bool fast_alter_partition= false;
+#endif
+  /*
+    Create .FRM for new version of table with a temporary name.
+    We don't log the statement, it will be logged later.
+
+    Keep information about keys in newly created table as it
+    will be used later to construct Alter_inplace_info object
+    and by fill_alter_inplace_info() call.
+  */
+  KEY *key_info;
+  uint key_count;
+  /*
+    Remember if the new definition has new VARCHAR column;
+    create_info->varchar will be reset in create_table_impl()/
+    mysql_prepare_create_table().
+  */
+  bool varchar= create_info->varchar, table_creation_was_logged= 0;
+  uint tables_opened;
+  handlerton *new_db_type, *old_db_type;
+  ha_rows copied=0, deleted=0;
+  LEX_CUSTRING frm= {0,0};
+  char index_file[FN_REFLEN], data_file[FN_REFLEN];
+  MDL_request target_mdl_request;
+  MDL_ticket *mdl_ticket= 0;
+  Alter_table_prelocking_strategy alter_prelocking_strategy;
   DBUG_ENTER("mysql_alter_table");
 
   /*
@@ -9517,17 +9548,38 @@ bool mysql_alter_table(THD *thd, const LEX_CSTRING *new_db,
   */
   table_list->required_type= TABLE_TYPE_NORMAL;
 
-  Alter_table_prelocking_strategy alter_prelocking_strategy;
-
   DEBUG_SYNC(thd, "alter_table_before_open_tables");
-  uint tables_opened;
 
   thd->open_options|= HA_OPEN_FOR_ALTER;
   thd->mdl_backup_ticket= 0;
-  bool error= open_tables(thd, &table_list, &tables_opened, 0,
+  error= open_tables(thd, &table_list, &tables_opened, 0,
-                          &alter_prelocking_strategy);
+                     &alter_prelocking_strategy);
   thd->open_options&= ~HA_OPEN_FOR_ALTER;
 
+  if (unlikely(error))
+  {
+    if (if_exists)
+    {
+      int tmp_errno= thd->get_stmt_da()->sql_errno();
+      if (tmp_errno == ER_NO_SUCH_TABLE)
+      {
+        /*
+          ALTER TABLE IF EXISTS was used on not existing table
+          We have to log the query on a slave as the table may be a shared one
+          from the master and we need to ensure that the next slave can see
+          the statement as this slave may not have the table shared
+        */
+        thd->clear_error();
+        if (thd->slave_thread &&
+            write_bin_log(thd, true, thd->query(), thd->query_length()))
+          DBUG_RETURN(true);
+        my_ok(thd);
+        DBUG_RETURN(0);
+      }
+    }
+    DBUG_RETURN(true);
+  }
+
 #ifdef WITH_WSREP
   if (WSREP(thd) &&
       (thd->lex->sql_command == SQLCOM_ALTER_TABLE ||
@@ -9539,10 +9591,8 @@ bool mysql_alter_table(THD *thd, const LEX_CSTRING *new_db,
 
   DEBUG_SYNC(thd, "alter_table_after_open_tables");
 
-  TABLE *table= table_list->table;
+  table= table_list->table;
-  bool versioned= table && table->versioned();
+  if (table->versioned())
-
-  if (versioned)
   {
     if (handlerton *hton1= create_info->db_type)
     {
@@ -9577,11 +9627,12 @@ bool mysql_alter_table(THD *thd, const LEX_CSTRING *new_db,
                   };);
 #endif // WITH_WSREP
 
-  if (unlikely(error))
+  Alter_table_ctx alter_ctx(thd, table_list, tables_opened, new_db, new_name);
-    DBUG_RETURN(true);
+  mdl_ticket= table->mdl_ticket;
+
+  table_creation_was_logged= table->s->table_creation_was_logged;
 
   table->use_all_columns();
-  MDL_ticket *mdl_ticket= table->mdl_ticket;
 
   /*
     Prohibit changing of the UNION list of a non-temporary MERGE table
@@ -9598,10 +9649,6 @@ bool mysql_alter_table(THD *thd, const LEX_CSTRING *new_db,
     DBUG_RETURN(true);
   }
 
-  Alter_table_ctx alter_ctx(thd, table_list, tables_opened, new_db, new_name);
-
-  MDL_request target_mdl_request;
-
   /* Check that we are not trying to rename to an existing table */
   if (alter_ctx.is_table_renamed())
   {
@@ -9833,8 +9880,7 @@ do_continue:;
     my_ok(thd, 0L, 0L, alter_ctx.tmp_buff);
 
     /* We don't replicate alter table statement on temporary tables */
-    if (table->s->tmp_table == NO_TMP_TABLE ||
+    if (table_creation_was_logged)
-        !thd->is_current_stmt_binlog_format_row())
     {
       if (write_bin_log(thd, true, thd->query(), thd->query_length()))
         DBUG_RETURN(true);
@@ -9880,8 +9926,6 @@ do_continue:;
   /* We have to do full alter table. */
 
 #ifdef WITH_PARTITION_STORAGE_ENGINE
-  bool partition_changed= false;
-  bool fast_alter_partition= false;
   {
     if (prep_alter_part_table(thd, table, alter_info, create_info,
                               &partition_changed, &fast_alter_partition))
@@ -10000,10 +10044,9 @@ do_continue:;
     It's therefore important that the assignment below is done
     after prep_alter_part_table.
   */
-  handlerton *new_db_type= create_info->db_type;
+  new_db_type= create_info->db_type;
-  handlerton *old_db_type= table->s->db_type();
+  old_db_type= table->s->db_type();
-  TABLE *new_table= NULL;
+  new_table= NULL;
-  ha_rows copied=0,deleted=0;
 
   /*
     Handling of symlinked tables:
@@ -10029,8 +10072,6 @@ do_continue:;
       Copy data.
       Remove old table and symlinks.
   */
-  char index_file[FN_REFLEN], data_file[FN_REFLEN];
-
   if (!alter_ctx.is_database_changed())
   {
     if (create_info->index_file_name)
@@ -10058,24 +10099,6 @@ do_continue:;
 
   DEBUG_SYNC(thd, "alter_table_before_create_table_no_lock");
 
-  /*
-    Create .FRM for new version of table with a temporary name.
-    We don't log the statement, it will be logged later.
-
-    Keep information about keys in newly created table as it
-    will be used later to construct Alter_inplace_info object
-    and by fill_alter_inplace_info() call.
-  */
-  KEY *key_info;
-  uint key_count;
-  /*
-    Remember if the new definition has new VARCHAR column;
-    create_info->varchar will be reset in create_table_impl()/
-    mysql_prepare_create_table().
-  */
-  bool varchar= create_info->varchar;
-  LEX_CUSTRING frm= {0,0};
-
   tmp_disable_binlog(thd);
   create_info->options|=HA_CREATE_TMP_ALTER;
   error= create_table_impl(thd, alter_ctx.db, alter_ctx.table_name,
@@ -10091,9 +10114,6 @@ do_continue:;
     DBUG_RETURN(true);
   }
 
-  /* Remember that we have not created table in storage engine yet. */
-  bool no_ha_table= true;
-
   if (alter_info->requested_algorithm != Alter_info::ALTER_TABLE_ALGORITHM_COPY)
   {
     Alter_inplace_info ha_alter_info(create_info, alter_info,
@@ -10313,9 +10333,7 @@ do_continue:;
                                  order_num, order, &copied, &deleted,
                                  alter_info->keys_onoff,
                                  &alter_ctx))
-    {
       goto err_new_table_cleanup;
-    }
   }
   else
   {
@@ -11088,8 +11106,8 @@ bool mysql_recreate_table(THD *thd, TABLE_LIST *table_list, bool table_copy)
     alter_info.requested_algorithm= Alter_info::ALTER_TABLE_ALGORITHM_COPY;
 
   bool res= mysql_alter_table(thd, &null_clex_str, &null_clex_str, &create_info,
-                                table_list, &alter_info, 0,
+                              table_list, &alter_info, 0,
-                                (ORDER *) 0, 0);
+                              (ORDER *) 0, 0, 0);
   table_list->next_global= next_table;
   DBUG_RETURN(res);
 }
@@ -11241,6 +11259,7 @@ err:
   @retval true  Engine not available/supported, error has been reported.
   @retval false Engine available/supported.
 */
+
 bool check_engine(THD *thd, const char *db_name,
                   const char *table_name, HA_CREATE_INFO *create_info)
 {

sql/sql_table.h

@@ -217,11 +217,13 @@ bool mysql_prepare_alter_table(THD *thd, TABLE *table,
                                Alter_table_ctx *alter_ctx);
 bool mysql_trans_prepare_alter_copy_data(THD *thd);
 bool mysql_trans_commit_alter_copy_data(THD *thd);
-bool mysql_alter_table(THD *thd, const LEX_CSTRING *new_db, const LEX_CSTRING *new_name,
+bool mysql_alter_table(THD *thd, const LEX_CSTRING *new_db,
+                       const LEX_CSTRING *new_name,
                        HA_CREATE_INFO *create_info,
                        TABLE_LIST *table_list,
                        Alter_info *alter_info,
-                       uint order_num, ORDER *order, bool ignore);
+                       uint order_num, ORDER *order, bool ignore,
+                       bool if_exists);
 bool mysql_compare_tables(TABLE *table,
                           Alter_info *alter_info,
                           HA_CREATE_INFO *create_info,
@@ -244,7 +246,7 @@ bool mysql_rm_table(THD *thd,TABLE_LIST *tables, bool if_exists,
 int mysql_rm_table_no_locks(THD *thd, TABLE_LIST *tables, bool if_exists,
                             bool drop_temporary, bool drop_view,
                             bool drop_sequence,
-                            bool log_query, bool dont_free_locks);
+                            bool dont_log_query, bool dont_free_locks);
 bool log_drop_table(THD *thd, const LEX_CSTRING *db_name,
                     const LEX_CSTRING *table_name, bool temporary_table);
 bool quick_rm_table(THD *thd, handlerton *base, const LEX_CSTRING *db,

sql/sql_yacc.yy

@@ -7098,10 +7098,11 @@ alter:
               MYSQL_YYABORT;
             DBUG_ASSERT(!Lex->m_sql_cmd);
           }
-          alter_options TABLE_SYM table_ident opt_lock_wait_timeout
+          alter_options TABLE_SYM opt_if_exists table_ident opt_lock_wait_timeout
           {
+            Lex->create_info.set($5);
             if (!Lex->first_select_lex()->
-                 add_table_to_list(thd, $5, NULL, TL_OPTION_UPDATING,
+                 add_table_to_list(thd, $6, NULL, TL_OPTION_UPDATING,
                                    TL_READ_NO_INSERT, MDL_SHARED_UPGRADABLE))
               MYSQL_YYABORT;
             Lex->first_select_lex()->db=
@@ -8298,9 +8299,10 @@ opt_no_write_to_binlog:
         ;
 
 rename:
-          RENAME table_or_tables
+          RENAME table_or_tables opt_if_exists
           {
             Lex->sql_command= SQLCOM_RENAME_TABLE;
+            Lex->create_info.set($3);
             if (Lex->main_select_push())
               MYSQL_YYABORT;
           }