InnoDB: ignore intra-database foreign key references between tables

when dropping database (Bug #3058)


innobase/dict/dict0crea.c:
  Add a parameter to row_drop_table_for_mysql()
innobase/dict/dict0dict.c:
  Make dict_tables_have_same_db() a global function
innobase/include/dict0dict.h:
  Make dict_tables_have_same_db() a global function
innobase/include/row0mysql.h:
  Add a parameter to row_drop_table_for_mysql()
innobase/row/row0mysql.c:
  Add a parameter "drop_db" to row_drop_table_for_mysql()
  to skip foreign constraint checks on tables in same database
innobase/trx/trx0roll.c:
  Add a parameter to row_drop_table_for_mysql()
sql/ha_innodb.cc:
  Add a parameter "drop_db" to row_drop_table_for_mysql()
  innobase_drop_database(): allocate namebuf dynamically

innobase/dict/dict0crea.c

@@ -999,13 +999,13 @@ dict_create_or_check_foreign_constraint_tables(void)
 	if (table1) {
 		fprintf(stderr,
 		"InnoDB: dropping incompletely created SYS_FOREIGN table\n");
-		row_drop_table_for_mysql((char *) "SYS_FOREIGN", trx);
+		row_drop_table_for_mysql((char*)"SYS_FOREIGN", trx, TRUE);
 	}
 
 	if (table2) {
 		fprintf(stderr,
 	"InnoDB: dropping incompletely created SYS_FOREIGN_COLS table\n");
-		row_drop_table_for_mysql((char *) "SYS_FOREIGN_COLS", trx);
+		row_drop_table_for_mysql((char*)"SYS_FOREIGN_COLS", trx, TRUE);
 	}
 
 	fprintf(stderr,
@@ -1054,8 +1054,8 @@ dict_create_or_check_foreign_constraint_tables(void)
 		fprintf(stderr,
 		"InnoDB: dropping incompletely created SYS_FOREIGN tables\n");
 
-		row_drop_table_for_mysql((char *) "SYS_FOREIGN", trx);
-		row_drop_table_for_mysql((char *) "SYS_FOREIGN_COLS", trx);
+		row_drop_table_for_mysql((char*)"SYS_FOREIGN", trx, TRUE);
+		row_drop_table_for_mysql((char*)"SYS_FOREIGN_COLS", trx, TRUE);
 
 		error = DB_MUST_GET_MORE_FILE_SPACE;
 	}

innobase/dict/dict0dict.c

@@ -177,7 +177,7 @@ mutex_t	dict_foreign_err_mutex; 	/* mutex protecting the foreign
 	
 /************************************************************************
 Checks if the database name in two table names is the same. */
-static
+
 ibool
 dict_tables_have_same_db(
 /*=====================*/

innobase/include/dict0dict.h

@@ -834,6 +834,17 @@ Releases the dictionary system mutex for MySQL. */
 void
 dict_mutex_exit_for_mysql(void);
 /*===========================*/
+/************************************************************************
+Checks if the database name in two table names is the same. */
+
+ibool
+dict_tables_have_same_db(
+/*=====================*/
+				/* out: TRUE if same db name */
+	const char*	name1,	/* in: table name in the form
+				dbname '/' tablename */
+	const char*	name2);	/* in: table name in the form
+				dbname '/' tablename */
 
 /* The following len must be at least 10000 bytes! */
 #define DICT_FOREIGN_ERR_BUF_LEN	10000

innobase/include/row0mysql.h

@@ -329,7 +329,8 @@ row_drop_table_for_mysql(
 /*=====================*/
 			/* out: error code or DB_SUCCESS */
 	char*	name,	/* in: table name */
-	trx_t*	trx);	/* in: transaction handle */
+	trx_t*	trx,	/* in: transaction handle */
+	ibool	drop_db);/* in: TRUE=dropping whole database */
 /*************************************************************************
 Drops a database for MySQL. */
 

innobase/row/row0mysql.c

@@ -1427,7 +1427,7 @@ row_create_table_for_mysql(
 			fprintf(stderr, 
      "InnoDB: Warning: cannot create table %s because tablespace full\n",
 				 table->name);
-		     	row_drop_table_for_mysql(table->name, trx);
+		     	row_drop_table_for_mysql(table->name, trx, FALSE);
 		} else {
 		       	ut_a(err == DB_DUPLICATE_KEY);
 
@@ -1542,7 +1542,7 @@ row_create_index_for_mysql(
 
 		trx_general_rollback_for_mysql(trx, FALSE, NULL);
 
-		row_drop_table_for_mysql(index->table_name, trx);
+		row_drop_table_for_mysql(index->table_name, trx, FALSE);
 
 		trx->error_state = DB_SUCCESS;
 	}
@@ -1607,7 +1607,7 @@ row_table_add_foreign_constraints(
 
 		trx_general_rollback_for_mysql(trx, FALSE, NULL);
 
-		row_drop_table_for_mysql(name, trx);
+		row_drop_table_for_mysql(name, trx, FALSE);
 
 		trx->error_state = DB_SUCCESS;
 	}
@@ -1638,7 +1638,7 @@ row_drop_table_for_mysql_in_background(
 							name); */
   	/* Drop the table in InnoDB */
 
-  	error = row_drop_table_for_mysql(name, trx);
+  	error = row_drop_table_for_mysql(name, trx, FALSE);
 
 	if (error != DB_SUCCESS) {
 		fprintf(stderr,
@@ -1795,9 +1795,10 @@ output by the master thread. */
 int
 row_drop_table_for_mysql(
 /*=====================*/
-				/* out: error code or DB_SUCCESS */
-	char*	name,		/* in: table name */
-	trx_t*	trx)		/* in: transaction handle */
+			/* out: error code or DB_SUCCESS */
+	char*	name,	/* in: table name */
+	trx_t*	trx,	/* in: transaction handle */
+	ibool	drop_db)/* in: TRUE=dropping whole database */
 {
 	dict_foreign_t*	foreign;
 	dict_table_t*	table;
@@ -1981,7 +1982,9 @@ row_drop_table_for_mysql(
 		foreign = UT_LIST_GET_NEXT(referenced_list, foreign);
 	}
 
-	if (foreign && trx->check_foreigns) {
+	if (foreign && trx->check_foreigns &&
+		!(drop_db && dict_tables_have_same_db(
+			name, foreign->foreign_table_name))) {
 		char*	buf	= dict_foreign_err_buf;
 
 		/* We only allow dropping a referenced table if
@@ -2112,7 +2115,6 @@ row_drop_database_for_mysql(
 		ut_a(strcmp(table_name, name) == 0);
 
 		table = dict_table_get_low(table_name);
-fprintf(stderr, "drop %p:%s\n", table, table_name);
 
 		ut_a(table);
 
@@ -2135,7 +2137,7 @@ fprintf(stderr, "drop %p:%s\n", table, table_name);
 		        goto loop;
 		}
 
-		err = row_drop_table_for_mysql(table_name, trx);
+		err = row_drop_table_for_mysql(table_name, trx, TRUE);
 
 		mem_free(table_name);
 

innobase/trx/trx0roll.c

@@ -469,7 +469,7 @@ trx_rollback_or_clean_all_without_sess(void)
 			fprintf(stderr,
 "InnoDB: Table found: dropping table %s in recovery\n", table->name);
 
-			err = row_drop_table_for_mysql(table->name, trx);
+			err = row_drop_table_for_mysql(table->name, trx, TRUE);
 
 			ut_a(err == (int) DB_SUCCESS);
 		}

sql/ha_innodb.cc

@@ -3631,7 +3631,8 @@ ha_innobase::delete_table(
 
   	/* Drop the table in InnoDB */
 
-  	error = row_drop_table_for_mysql(norm_name, trx);
+	error = row_drop_table_for_mysql(norm_name, trx,
+		thd->lex.sql_command == SQLCOM_DROP_DB);
 
 	/* Flush the log to reduce probability that the .frm files and
 	the InnoDB data dictionary get out-of-sync if the user runs
@@ -3670,7 +3671,7 @@ innobase_drop_database(
 	trx_t*	trx;
 	char*	ptr;
 	int	error;
-	char	namebuf[10000];
+	char*	namebuf;
 
 	/* Get the transaction associated with the current thd, or create one
 	if not yet created */
@@ -3690,6 +3691,7 @@ innobase_drop_database(
 	}
 
 	ptr++;
+	namebuf = my_malloc(len + 2, MYF(0));
 
 	memcpy(namebuf, ptr, len);
 	namebuf[len] = '/';
@@ -3706,6 +3708,7 @@ innobase_drop_database(
 	}
 
   	error = row_drop_database_for_mysql(namebuf, trx);
+	my_free(namebuf, MYF(0));
 
 	/* Flush the log to reduce probability that the .frm files and
 	the InnoDB data dictionary get out-of-sync if the user runs