Merge rurik.mysql.com:/home/igor/mysql-4.1-opt

into  rurik.mysql.com:/home/igor/mysql-5.0-opt


sql/opt_sum.cc:
  Auto merged
sql/sql_select.cc:
  Auto merged
sql/sql_select.h:
  Auto merged
mysql-test/r/func_group.result:
  SCCS merged
mysql-test/t/func_group.test:
  SCCS merged

1 files changed, 14 insertions, 3 deletions

diff --git a/sql/opt_sum.cc b/sql/opt_sum.cc
index 373753a7b80..4a7ec0c5928 100644
--- a/sql/opt_sum.cc
+++ b/sql/opt_sum.cc
@@ -569,6 +569,10 @@ static bool matching_cond(bool max_fl, TABLE_REF *ref, KEY *keyinfo,
       break;                        // Found a part od the key for the field
   }
 
+#if 0
+  if (part->length != (((Item_field*) args[0])->field)->field_length)
+    return 0;
+#endif
   bool is_field_part= part == field_part;
   if (!(is_field_part || eq_type))
     return 0;
@@ -608,7 +612,8 @@ static bool matching_cond(bool max_fl, TABLE_REF *ref, KEY *keyinfo,
     }
     else
     {
-      store_val_in_field(part->field, args[between && max_fl ? 2 : 1]);
+      store_val_in_field(part->field, args[between && max_fl ? 2 : 1],
+                         CHECK_FIELD_IGNORE);
       if (part->null_bit) 
         *key_ptr++= (byte) test(part->field->is_null());
       part->field->get_key_image((char*) key_ptr, part->length, Field::itRAW);
@@ -663,6 +668,8 @@ static bool matching_cond(bool max_fl, TABLE_REF *ref, KEY *keyinfo,
         field BETWEEN const1 AND const2
      3. all references to the columns from the same table as column field
         occur only in conjucts mentioned above.
+     4. each of k first components the index is not partial, i.e. is not
+        defined on a fixed length proper prefix of the field.
 
      If such an index exists the function through the ref parameter
      returns the key value to find max/min for the field using the index,
@@ -672,8 +679,8 @@ static bool matching_cond(bool max_fl, TABLE_REF *ref, KEY *keyinfo,
       of the whole search key)
 
   NOTE
-   This function may set table->key_read to 1, which must be reset after
-   index is used! (This can only happen when function returns 1)
+    This function may set table->key_read to 1, which must be reset after
+    index is used! (This can only happen when function returns 1)
 
   RETURN
     0   Index can not be used to optimize MIN(field)/MAX(field)
@@ -707,6 +714,10 @@ static bool find_key_for_maxmin(bool max_fl, TABLE_REF *ref,
       if (!(table->file->index_flags(idx, jdx, 0) & HA_READ_ORDER))
         return 0;
 
+        /* Check whether the index component is partial */
+      if (part->length < table->field[part->fieldnr-1]->pack_length())
+        break;
+
       if (field->eq(part->field))
       {
         ref->key= idx;