branches/zip: Preserve FOREIGN KEY constraints when creating a PRIMARY KEY.

innodb-index.test: Add some test cases for FOREIGN KEY constraints.

row_merge_rename_tables(): New function,
adapted from row_rename_table_for_mysql().

ha_innobase::add_index(): Use row_merge_rename_tables().

handler/ha_innodb.cc

@@ -8513,10 +8513,11 @@ ha_innobase::add_index(
 	table as a old table and drop the old table. */
 
 	if (new_primary) {
-		char*	old_name	= mem_heap_strdup(
-			heap, innodb_table->name);
-		char*	tmp_table_name	= innobase_create_temporary_tablename(
-			heap, '2', innodb_table->name);
+		const char*	old_name
+			= innodb_table->name;
+		const char*	tmp_name
+			= innobase_create_temporary_tablename(heap, '2',
+							      old_name);
 
 		trx_start_if_not_started(trx);
 
@@ -8527,7 +8528,7 @@ ha_innobase::add_index(
 
 		/* Write entry for UNDO */
 		error = row_undo_report_rename_table_dict_operation(
-			trx, old_name, indexed_table->name, tmp_table_name);
+			trx, old_name, indexed_table->name, tmp_name);
 
 		if (error != DB_SUCCESS) {
 
@@ -8538,15 +8539,10 @@ ha_innobase::add_index(
 
 		/* Set the commit flag to FALSE, we will commit the
 		transaction ourselves, required for UNDO */
-		error = innobase_rename_table(trx, innodb_table->name,
-					      tmp_table_name, FALSE);
-		if (error != DB_SUCCESS) {
 
-			goto func_exit;
-		}
+		error = row_merge_rename_tables(innodb_table, indexed_table,
+						tmp_name, trx);
 
-		error = innobase_rename_table(trx, indexed_table->name,
-					      old_name, FALSE);
 		if (error != DB_SUCCESS) {
 
 			goto func_exit;

include/row0merge.h

@@ -63,6 +63,20 @@ row_merge_drop_indexes(
 	dict_index_t**	index,		/* in: indexes to drop */
 	ulint		num_created);	/* in: number of elements in index[] */
 
+/*************************************************************************
+Rename the tables in the data dictionary. */
+
+ulint
+row_merge_rename_tables(
+/*====================*/
+					/* out: error code or DB_SUCCESS */
+	dict_table_t*	old_table,	/* in/out: old table, renamed to
+					tmp_name */
+	dict_table_t*	new_table,	/* in/out: new table, renamed to
+					old_table->name */
+	const char*	tmp_name,	/* in: new name for old_table */
+	trx_t*		trx);		/* in: transaction handle */
+
 /*************************************************************************
 Create a temporary table for creating a primary key, using the definition
 of an existing table. */

mysql-test/innodb-index.result

@@ -469,8 +469,9 @@ create table t1(a int not null, b int not null, c int, primary key (a), key (b))
 create table t3(a int not null, c int not null, d int, primary key (a), key (c)) engine = innodb;
 create table t4(a int not null, d int not null, e int, primary key (a), key (d)) engine = innodb;
 create table t2(a int not null, b int not null, c int not null, d int not null, e int,
-primary key (a), foreign key (b) references t1(b), foreign key (c) references t3(c),
-foreign key (d) references t4(d)) engine = innodb;
+foreign key (b) references t1(b) on delete cascade,
+foreign key (c) references t3(c), foreign key (d) references t4(d))
+engine = innodb;
 alter table t1 drop index b;
 ERROR HY000: Cannot drop index 'b': needed in a foreign key constraint
 alter table t3 drop index c;
@@ -481,7 +482,8 @@ alter table t2 drop index b;
 ERROR HY000: Cannot drop index 'b': needed in a foreign key constraint
 alter table t2 drop index b, drop index c, drop index d;
 ERROR HY000: Cannot drop index 'b': needed in a foreign key constraint
-set foreign_key_checks=0;
+create unique index dc on t2 (d,c);
+alter table t2 add primary key (a);
 insert into t1 values (1,1,1);
 insert into t3 values (1,1,1);
 insert into t4 values (1,1,1);
@@ -497,17 +499,17 @@ t2	CREATE TABLE `t2` (
   `d` int(11) NOT NULL,
   `e` int(11) DEFAULT NULL,
   PRIMARY KEY (`a`),
+  UNIQUE KEY `dc` (`d`,`c`),
   KEY `c` (`c`),
-  KEY `d` (`d`),
   KEY `b` (`b`),
-  CONSTRAINT `t2_ibfk_1` FOREIGN KEY (`b`) REFERENCES `t1` (`b`),
+  CONSTRAINT `t2_ibfk_1` FOREIGN KEY (`b`) REFERENCES `t1` (`b`) ON DELETE CASCADE,
   CONSTRAINT `t2_ibfk_2` FOREIGN KEY (`c`) REFERENCES `t3` (`c`),
   CONSTRAINT `t2_ibfk_3` FOREIGN KEY (`d`) REFERENCES `t4` (`d`)
 ) ENGINE=InnoDB DEFAULT CHARSET=latin1
-set foreign_key_checks=1;
-set foreign_key_checks=0;
-drop table if exists t1,t2,t3,t4;
-set foreign_key_checks=1;
+delete from t1;
+select * from t2;
+a	b	c	d	e
+drop table if exists t2,t1,t3,t4;
 create table t1(a int not null, b int, c char(10), d varchar(20), primary key (a)) 
 engine = innodb default charset=utf8;
 insert into t1 values (1,1,'ab','ab'),(2,2,'ac','ac'),(3,2,'ad','ad'),(4,4,'afe','afe');

mysql-test/innodb-index.test

@@ -111,8 +111,9 @@ create table t1(a int not null, b int not null, c int, primary key (a), key (b))
 create table t3(a int not null, c int not null, d int, primary key (a), key (c)) engine = innodb;
 create table t4(a int not null, d int not null, e int, primary key (a), key (d)) engine = innodb;
 create table t2(a int not null, b int not null, c int not null, d int not null, e int,
-primary key (a), foreign key (b) references t1(b), foreign key (c) references t3(c),
-foreign key (d) references t4(d)) engine = innodb;
+foreign key (b) references t1(b) on delete cascade,
+foreign key (c) references t3(c), foreign key (d) references t4(d))
+engine = innodb;
 --error ER_DROP_INDEX_FK
 alter table t1 drop index b;
 --error ER_DROP_INDEX_FK
@@ -123,7 +124,10 @@ alter table t4 drop index d;
 alter table t2 drop index b;
 --error ER_DROP_INDEX_FK
 alter table t2 drop index b, drop index c, drop index d;
-set foreign_key_checks=0;
+-- Apparently, the following makes mysql_alter_table() drop index d.
+create unique index dc on t2 (d,c);
+-- This should preserve the foreign key constraints.
+alter table t2 add primary key (a);
 insert into t1 values (1,1,1);
 insert into t3 values (1,1,1);
 insert into t4 values (1,1,1);
@@ -131,13 +135,10 @@ insert into t2 values (1,1,1,1,1);
 commit;
 alter table t2 drop index b, add index (b);
 show create table t2;
-set foreign_key_checks=1;
+delete from t1;
+select * from t2;
 
-set foreign_key_checks=0;
---disable_warnings
-drop table if exists t1,t2,t3,t4;
---enable_warnings
-set foreign_key_checks=1;
+drop table if exists t2,t1,t3,t4;
 
 create table t1(a int not null, b int, c char(10), d varchar(20), primary key (a)) 
 engine = innodb default charset=utf8;

row/row0merge.c

@@ -1657,6 +1657,77 @@ row_merge_rename_index(
 	return(err);
 }
 
+/*************************************************************************
+Rename the tables in the data dictionary. */
+
+ulint
+row_merge_rename_tables(
+/*====================*/
+					/* out: error code or DB_SUCCESS */
+	dict_table_t*	old_table,	/* in/out: old table, renamed to
+					tmp_name */
+	dict_table_t*	new_table,	/* in/out: new table, renamed to
+					old_table->name */
+	const char*	tmp_name,	/* in: new name for old_table */
+	trx_t*		trx)		/* in: transaction handle */
+{
+	ulint		err	= DB_ERROR;
+	pars_info_t*	info;
+	const char*	old_name= old_table->name;
+
+	ut_ad(trx->mysql_thread_id == os_thread_get_curr_id());
+	ut_ad(old_table != new_table);
+
+	trx->op_info = "renaming tables";
+	trx_start_if_not_started(trx);
+
+	/* We use the private SQL parser of Innobase to generate the query
+	graphs needed in updating the dictionary data in system tables. */
+
+	info = pars_info_create();
+
+	pars_info_add_str_literal(info, "new_name", new_table->name);
+	pars_info_add_str_literal(info, "old_name", old_name);
+	pars_info_add_str_literal(info, "tmp_name", tmp_name);
+
+	err = que_eval_sql(info,
+			   "PROCEDURE RENAME_TABLES () IS\n"
+			   "BEGIN\n"
+			   "UPDATE SYS_TABLES SET NAME = :tmp_name\n"
+			   " WHERE NAME = :old_name;\n"
+			   "UPDATE SYS_TABLES SET NAME = :old_name\n"
+			   " WHERE NAME = :new_name;\n"
+			   "END;\n", FALSE, trx);
+
+	if (err != DB_SUCCESS) {
+
+		goto err_exit;
+	}
+
+	/* The following calls will also rename the .ibd data files if
+	the tables are stored in a single-table tablespace */
+
+	if (!dict_table_rename_in_cache(old_table, tmp_name, FALSE)
+	    || !dict_table_rename_in_cache(new_table, old_name, FALSE)) {
+
+		err = DB_ERROR;
+		goto err_exit;
+	}
+
+	err = dict_load_foreigns(old_name, TRUE);
+
+	if (err != DB_SUCCESS) {
+err_exit:
+		trx->error_state = DB_SUCCESS;
+		trx_general_rollback_for_mysql(trx, FALSE, NULL);
+		trx->error_state = DB_SUCCESS;
+	}
+
+	trx->op_info = "";
+
+	return(err);
+}
+
 /*************************************************************************
 Create the index and load in to the dictionary. */