Fixed a bug no error message for ALTER with InnoDB and AUTO_INCREMENT (Bug #7061).

sql/ha_innodb.cc

@@ -1326,7 +1326,13 @@ innobase_commit(
 			&innodb_dummy_stmt_trx_handle: the latter means
 			that the current SQL statement ended */
 {
-	trx_t*	trx;
+	trx_t*		trx;
+	dict_table_t*	table;
+	ib_longlong	auto_inc_value;
+        ib_longlong	aic_new;
+	char 		table_name[1000];
+	ulint		db_name_len;
+	ulint		table_name_len;
 
   	DBUG_ENTER("innobase_commit");
   	DBUG_PRINT("trans", ("ending transaction"));
@@ -1361,6 +1367,41 @@ innobase_commit(
 "InnoDB: but trx->conc_state != TRX_NOT_STARTED\n");
 	}
 
+	if (thd->lex->sql_command == SQLCOM_ALTER_TABLE &&
+	   (thd->lex->create_info.used_fields & HA_CREATE_USED_AUTO) &&
+	   (thd->lex->create_info.auto_increment_value != 0)) {
+
+		/* Query was ALTER TABLE...AUTO_INC = x; Find out a table
+		definition from the dictionary and get the current value
+		of the auto increment field. Set a new value to the
+		auto increment field if the new value is creater than 
+		the current value. */
+
+		aic_new = thd->lex->create_info.auto_increment_value;
+		db_name_len = strlen(thd->lex->query_tables->db);
+		table_name_len = strlen(thd->lex->query_tables->real_name);
+
+		ut_ad((db_name_len + 1 + table_name_len) < 999);
+		strcpy(table_name, thd->lex->query_tables->db);
+		strcat(table_name, "/");
+		strcat(table_name, thd->lex->query_tables->real_name);
+
+		table = dict_table_get(table_name, trx);
+
+		if (table) {
+			auto_inc_value = dict_table_autoinc_peek(table);
+
+			if( auto_inc_value < aic_new) {
+
+				/* We have to decrease the new auto increment
+				value by one because this function will increase
+				the value given by one. */
+
+				dict_table_autoinc_update(table, aic_new - 1);
+			}
+		}
+	}
+
 	if (trx_handle != (void*)&innodb_dummy_stmt_trx_handle
 	    || (!(thd->options & (OPTION_NOT_AUTOCOMMIT | OPTION_BEGIN)))) {