Fixed BUG#3117: LAST_INSERT_ID() works incorrectly inside stored procedure.

This turned out to be a problem for prepared statements as well; the id was
evaluated once, at parse time.


mysql-test/r/auto_increment.result:
  Updated results after bugfix in last_insert_id().
mysql-test/r/query_cache.result:
  Updated results after bugfix in last_insert_id().
mysql-test/r/variables.result:
  Updated results after bugfix in last_insert_id().
sql/item_func.cc:
  Fixed bug in last_insert_id(); get id at each evaluation (and not in the parser).
  Renamed the class Item_func_set_last_insert_id too, since it's not only for setting.
sql/item_func.h:
  Fixed bug in last_insert_id(); get id at each evaluation (and not in the parser).
  Renamed the class Item_func_set_last_insert_id too, since it's not only for setting.
sql/sql_yacc.yy:
  Fixed bug in last_insert_id(); get id at each evaluation (and not in the parser).
  Renamed the class Item_func_set_last_insert_id too, since it's not only for setting.
tests/client_test.c:
  Test case for last_insert_id() in prepared statements.

3 files changed, 20 insertions, 11 deletions

diff --git a/sql/item_func.cc b/sql/item_func.cc
index 5151fb2876d..9f80686e72c 100644
--- a/sql/item_func.cc
+++ b/sql/item_func.cc
@@ -2139,13 +2139,22 @@ longlong Item_func_release_lock::val_int()
 }
 
 
-longlong Item_func_set_last_insert_id::val_int()
+longlong Item_func_last_insert_id::val_int()
 {
   DBUG_ASSERT(fixed == 1);
-  longlong value=args[0]->val_int();
-  current_thd->insert_id(value);
-  null_value=args[0]->null_value;
-  return value;
+  if (arg_count)
+  {
+    longlong value=args[0]->val_int();
+    current_thd->insert_id(value);
+    null_value=args[0]->null_value;
+    return value;
+  }
+  else
+  {
+    Item *it= get_system_var(current_thd, OPT_SESSION, "last_insert_id", 14,
+			     "last_insert_id()");
+    return it->val_int();
+  }
 }
 
 /* This function is just used to test speed of different functions */
diff --git a/sql/item_func.h b/sql/item_func.h
index 4558c1c6f62..4142498af6c 100644
--- a/sql/item_func.h
+++ b/sql/item_func.h
@@ -729,13 +729,14 @@ public:
 };
 
 
-class Item_func_set_last_insert_id :public Item_int_func
+class Item_func_last_insert_id :public Item_int_func
 {
 public:
-  Item_func_set_last_insert_id(Item *a) :Item_int_func(a) {}
+  Item_func_last_insert_id() :Item_int_func() {}
+  Item_func_last_insert_id(Item *a) :Item_int_func(a) {}
   longlong val_int();
   const char *func_name() const { return "last_insert_id"; }
-  void fix_length_and_dec() { max_length=args[0]->max_length; }
+  void fix_length_and_dec() { if (arg_count) max_length= args[0]->max_length; }
 };
 
 class Item_func_benchmark :public Item_int_func
diff --git a/sql/sql_yacc.yy b/sql/sql_yacc.yy
index 5987a69819e..1d30bb210d4 100644
--- a/sql/sql_yacc.yy
+++ b/sql/sql_yacc.yy
@@ -2750,13 +2750,12 @@ simple_expr:
           }
 	| LAST_INSERT_ID '(' ')'
 	  {
-	    $$= get_system_var(YYTHD, OPT_SESSION, "last_insert_id", 14,
-			      "last_insert_id()");
+	    $$= new Item_func_last_insert_id();
 	    Lex->safe_to_cache_query= 0;
 	  }
 	| LAST_INSERT_ID '(' expr ')'
 	  {
-	    $$= new Item_func_set_last_insert_id($3);
+	    $$= new Item_func_last_insert_id($3);
 	    Lex->safe_to_cache_query= 0;
 	  }
 	| LEFT '(' expr ',' expr ')'