diff options
Diffstat (limited to 'sql/opt_range.cc')
| -rw-r--r-- | sql/opt_range.cc | 18 |
1 files changed, 12 insertions, 6 deletions
diff --git a/sql/opt_range.cc b/sql/opt_range.cc index f33a2d312b4..d1f99604959 100644 --- a/sql/opt_range.cc +++ b/sql/opt_range.cc @@ -936,8 +936,11 @@ get_mm_leaf(PARAM *param, Field *field, KEY_PART *key_part, if (!(res= value->val_str(&tmp))) DBUG_RETURN(&null_element); - // Check if this was a function. This should have be optimized away - // in the sql_select.cc + /* + TODO: + Check if this was a function. This should have be optimized away + in the sql_select.cc + */ if (res != &tmp) { tmp.copy(*res); // Get own copy @@ -1017,8 +1020,10 @@ get_mm_leaf(PARAM *param, Field *field, KEY_PART *key_part, type != Item_func::EQUAL_FUNC) DBUG_RETURN(0); // Can't optimize this - /* We can't always use indexes when comparing a string index to a number */ - /* cmp_type() is checked to allow compare of dates to numbers */ + /* + We can't always use indexes when comparing a string index to a number + cmp_type() is checked to allow compare of dates to numbers + */ if (field->result_type() == STRING_RESULT && value->result_type() != STRING_RESULT && field->cmp_type() != value->result_type()) @@ -1026,6 +1031,7 @@ get_mm_leaf(PARAM *param, Field *field, KEY_PART *key_part, if (value->save_in_field(field)) { + /* This happens when we try to insert a NULL field in a not null column */ // TODO; Check if we can we remove the following block. if (type == Item_func::EQUAL_FUNC) { @@ -1037,7 +1043,7 @@ get_mm_leaf(PARAM *param, Field *field, KEY_PART *key_part, *str = 1; DBUG_RETURN(new SEL_ARG(field,str,str)); } - DBUG_RETURN(&null_element); // NULL is never true + DBUG_RETURN(&null_element); // cmp with NULL is never true } // Get local copy of key char *str= (char*) alloc_root(param->mem_root, @@ -1045,7 +1051,7 @@ get_mm_leaf(PARAM *param, Field *field, KEY_PART *key_part, if (!str) DBUG_RETURN(0); if (maybe_null) - *str=0; // Not NULL + *str= (char) field->is_real_null(); // Set to 1 if null field->get_key_image(str+maybe_null,key_part->part_length); if (!(tree=new SEL_ARG(field,str,str))) DBUG_RETURN(0); |