mariadb/sql/sql_trigger.h
dlenev@brandersnatch.localdomain d201074611 Fix for bug #5888 "Triggers with nonexistent columns cause packets
out of order". (final version)

Now instead of binding Item_trigger_field to TABLE objects during
trigger definition parsing at table open, we perform pass through
special list of all such objects in trigger. This allows easily check
all references to fields in old/new version of row in trigger during
execution of CREATE TRIGGER statement (this is more courtesy for users
since we can't check everything anyway).
We also report that such reference is bad by returning error from
Item_trigger_field::fix_fields() method (instead of setup_field())
This means that if trigger is broken we will bark during trigger
execution instead of trigger definition parsing at table open.
(i.e. now we allow to open tables with broken triggers).
2004-11-24 12:24:02 +03:00

71 lines
1.9 KiB
C++

/*
This class holds all information about triggers of table.
QQ: Will it be merged into TABLE in future ?
*/
class Table_triggers_list: public Sql_alloc
{
/* Triggers as SPs grouped by event, action_time */
sp_head *bodies[3][2];
/*
Copy of TABLE::Field array with field pointers set to old version
of record, used for OLD values in trigger on UPDATE.
*/
Field **old_field;
/*
Names of triggers.
Should correspond to order of triggers on definitions_list,
used in CREATE/DROP TRIGGER for looking up trigger by name.
*/
List<LEX_STRING> names_list;
public:
/*
Field responsible for storing triggers definitions in file.
It have to be public because we are using it directly from parser.
*/
List<LEX_STRING> definitions_list;
Table_triggers_list():
old_field(0)
{
bzero((char *)bodies, sizeof(bodies));
}
~Table_triggers_list();
bool create_trigger(THD *thd, TABLE_LIST *table);
bool drop_trigger(THD *thd, TABLE_LIST *table);
bool process_triggers(THD *thd, trg_event_type event,
trg_action_time_type time_type)
{
int res= 0;
if (bodies[event][time_type])
{
/*
Similar to function invocation we don't need to surpress sending of
ok packets here because don't allow execute statements from trigger.
FIXME: We should juggle with security context here (because trigger
should be invoked with creator rights).
*/
res= bodies[event][time_type]->execute_function(thd, 0, 0, 0);
}
return res;
}
static bool check_n_load(THD *thd, const char *db, const char *table_name,
TABLE *table);
bool has_delete_triggers()
{
return (bodies[TRG_EVENT_DELETE][TRG_ACTION_BEFORE] ||
bodies[TRG_EVENT_DELETE][TRG_ACTION_AFTER]);
}
friend class Item_trigger_field;
private:
bool prepare_old_row_accessors(TABLE *table);
};