Bug#16461: connection_id() does not work properly inside trigger

CONNECTION_ID() was implemented as a constant Item, i.e. an instance of
Item_static_int_func class holding value computed at creation time.
Since Items are created on parsing, and trigger statements are parsed
on table open, the first connection to open a particular table would
effectively set its own CONNECTION_ID() inside trigger statements for
that table.

Re-implement CONNECTION_ID() as a class derived from Item_int_func, and
compute connection_id on every call to fix_fields().


mysql-test/r/trigger.result:
  Add result for bug#16461.
mysql-test/t/trigger.test:
  Add test case for bug#16461.
sql/item.cc:
  Remove now unused class Item_static_int_func.
sql/item.h:
  Remove now unused class Item_static_int_func.
sql/item_create.cc:
  Use new implementation of CONNECTION_ID().
sql/item_func.cc:
  Re-implement CONNECTION_ID() as Item_func_connection_id
  (was Item_static_int_func).  Set max_length to 10, as it was before.
  Compute connection_id dynamically on every call to fix_fields().
sql/item_func.h:
  Re-implement CONNECTION_ID() as Item_func_connection_id
  (was Item_static_int_func).

1 files changed, 0 insertions, 12 deletions

diff --git a/sql/item.h b/sql/item.h
index 3b96091af38..d33e0ae34be 100644
--- a/sql/item.h
+++ b/sql/item.h
@@ -1387,18 +1387,6 @@ public:
 };
 
 
-class Item_static_int_func :public Item_int
-{
-  const char *func_name;
-public:
-  Item_static_int_func(const char *str_arg, longlong i, uint length)
-    :Item_int(NullS, i, length), func_name(str_arg)
-  {}
-  Item *safe_charset_converter(CHARSET_INFO *tocs);
-  void print(String *str) { str->append(func_name); }
-};
-
-
 class Item_uint :public Item_int
 {
 public: