database/mariadb
1
0
Fork 0
mirror of https://github.com/MariaDB/server.git synced 2026-01-06 05:22:24 +03:00
Code Activity

InnoDB: limit the recursion depth for ON (UPDATE|DELETE) CASCADE

Browse Source 
(Bug #4446)
This commit is contained in:
marko@hundin.mysql.fi
2004-07-15 15:46:22 +03:00
parent 0614f8c718
commit 20b60510e9
3 changed files with 91 additions and 13 deletions
Download Patch File Download Diff File Expand all files Collapse all files

78
innobase/row/row0ins.c
View File

@@ -370,6 +370,32 @@ row_ins_cascade_ancestor_updates_table(
return(FALSE);
}
/*************************************************************************
Returns the number of ancestor UPDATE or DELETE nodes of a
cascaded update/delete node. */
static
ulint
row_ins_cascade_n_ancestors(
/*========================*/
/* out: number of ancestors */
que_node_t* node) /* in: node in a query graph */
{
que_node_t* parent;
ulint n_ancestors = 0;
parent = que_node_get_parent(node);
while (que_node_get_type(parent) == QUE_NODE_UPDATE) {
n_ancestors++;
parent = que_node_get_parent(parent);
ut_a(parent);
}
return(n_ancestors);
}
/**********************************************************************
Calculates the update vector node->cascade->update for a child table in
a cascaded update. */
@@ -615,6 +641,34 @@ row_ins_foreign_report_add_err(
mutex_exit(&dict_foreign_err_mutex);
}
/*************************************************************************
Invalidate the query cache for the given table. */
static
void
row_ins_invalidate_query_cache(
/*===========================*/
que_thr_t* thr, /* in: query thread whose run_node
is an update node */
const char* name) /* in: table name prefixed with
database name and a '/' character */
{
char* buf;
char* ptr;
ulint len = strlen(name) + 1;
buf = mem_strdupl(name, len);
ptr = strchr(buf, '/');
ut_a(ptr);
*ptr = '\0';
/* We call a function in ha_innodb.cc */
#ifndef UNIV_HOTBACKUP
innobase_invalidate_query_cache(thr_get_trx(thr), buf, len);
#endif
mem_free(buf);
}
/*************************************************************************
Perform referential actions or checks when a parent row is deleted or updated
and the constraint had an ON DELETE or ON UPDATE condition which was not
@@ -650,26 +704,14 @@ row_ins_foreign_check_on_constraint(
ulint n_to_update;
ulint err;
ulint i;
char* ptr;
char table_name_buf[1000];
ut_a(thr && foreign && pcur && mtr);
/* Since we are going to delete or update a row, we have to invalidate
the MySQL query cache for table */
ut_a(ut_strlen(table->name) < 998);
strcpy(table_name_buf, table->name);
row_ins_invalidate_query_cache(thr, table->name);
ptr = strchr(table_name_buf, '/');
ut_a(ptr);
*ptr = '\0';
/* We call a function in ha_innodb.cc */
#ifndef UNIV_HOTBACKUP
innobase_invalidate_query_cache(thr_get_trx(thr), table_name_buf,
ut_strlen(table->name) + 1);
#endif
node = thr->run_node;
if (node->is_delete && 0 == (foreign->type &
@@ -756,6 +798,16 @@ row_ins_foreign_check_on_constraint(
goto nonstandard_exit_func;
}
if (row_ins_cascade_n_ancestors(cascade) >= 15) {
err = DB_ROW_IS_REFERENCED;
row_ins_foreign_report_err(
(char*)"Trying a too deep cascaded delete or update\n",
thr, foreign, btr_pcur_get_rec(pcur), entry);
goto nonstandard_exit_func;
}
index = btr_pcur_get_btr_cur(pcur)->index;
ut_a(index == foreign->foreign_index);

12
mysql-test/r/innodb.result
View File

@@ -1259,3 +1259,15 @@ Cannot delete or update a parent row: a foreign key constraint fails
update t3 set t3.id=7 where t1.id =1 and t2.id = t1.id and t3.id = t2.id;
Unknown table 't1' in where clause
drop table t3,t2,t1;
create table t1(
id int primary key,
pid int,
index(pid),
foreign key(pid) references t1(id) on delete cascade) type=innodb;
insert into t1 values(0,0),(1,0),(2,1),(3,2),(4,3),(5,4),(6,5),(7,6),
(8,7),(9,8),(10,9),(11,10),(12,11),(13,12),(14,13),(15,14);
delete from t1 where id=0;
Cannot delete or update a parent row: a foreign key constraint fails
delete from t1 where id=15;
delete from t1 where id=0;
drop table t1;

14
mysql-test/t/innodb.test
View File

@@ -896,3 +896,17 @@ update t1,t2,t3 set t3.id=5, t2.id=6, t1.id=7 where t1.id =1 and t2.id = t1.id
--error 1109
update t3 set t3.id=7 where t1.id =1 and t2.id = t1.id and t3.id = t2.id;
drop table t3,t2,t1;
create table t1(
id int primary key,
pid int,
index(pid),
foreign key(pid) references t1(id) on delete cascade) type=innodb;
insert into t1 values(0,0),(1,0),(2,1),(3,2),(4,3),(5,4),(6,5),(7,6),
(8,7),(9,8),(10,9),(11,10),(12,11),(13,12),(14,13),(15,14);
-- error 1217
delete from t1 where id=0;
delete from t1 where id=15;
delete from t1 where id=0;
drop table t1;