row0mysql.h, ha_innodb.cc:

  Sergey Petrunia's ROR code fails to tell handlers that they should retrieve the primary key columns; let InnoDB ALWAYS retrieve them, to fix many bugs and potential bugs

innobase/include/row0mysql.h

@@ -547,7 +547,10 @@ struct row_prebuilt_struct {
 					format */
 	ulint		hint_need_to_fetch_extra_cols;
 					/* normally this is set to 0; if this
-					is set to ROW_RETRIEVE_PRIMARY_KEY,
+					is set to ROW_RETRIEVE_PRIMARY_KEY
+					(that value is obsolete starting from
+					5.0.2, because we always fetch the
+					primary key cols),
 					then we should at least retrieve all
 					columns in the primary key; if this
 					is set to ROW_RETRIEVE_ALL_COLS, then
@@ -620,6 +623,9 @@ struct row_prebuilt_struct {
 
 /* Values for hint_need_to_fetch_extra_cols */
 #define ROW_RETRIEVE_PRIMARY_KEY	1
+					/* value 1 is obsolete starting from
+					5.0.2, because we always fetch the
+					primary key cols */
 #define ROW_RETRIEVE_ALL_COLS		2
 
 

sql/ha_innodb.cc

@@ -2208,7 +2208,13 @@ build_template(
 	ulint		n_fields;
 	ulint		n_requested_fields	= 0;
 	ibool		fetch_all_in_key	= FALSE;
-	ibool		fetch_primary_key_cols	= FALSE;
+	ibool		fetch_primary_key_cols	= TRUE; /* The ROR code in
+						opt_range.cc assumes that the
+						primary key cols are always
+						retrieved. Starting from
+						MySQL-5.0.2, let us always
+						fetch them, even though it
+						wastes some CPU. */ 
 	ulint		i;
 
 	if (prebuilt->select_lock_type == LOCK_X) {