diff options
Diffstat (limited to 'sql/item_buff.cc')
-rw-r--r-- | sql/item_buff.cc | 14 |
1 files changed, 10 insertions, 4 deletions
diff --git a/sql/item_buff.cc b/sql/item_buff.cc index b0dbadcfda2..8c4224404d0 100644 --- a/sql/item_buff.cc +++ b/sql/item_buff.cc @@ -128,14 +128,20 @@ bool Cached_item_int::cmp(void) bool Cached_item_field::cmp(void) { - bool tmp= field->cmp(buff) != 0; // This is not a blob! - if (tmp) - field->get_image(buff,length,field->charset()); + bool tmp= FALSE; // Value is identical + /* Note that field can't be a blob here ! */ if (null_value != field->is_null()) { null_value= !null_value; - tmp=TRUE; + tmp= TRUE; // Value has changed } + + /* + If value is not null and value changed (from null to not null or + becasue of value change), then copy the new value to buffer. + */ + if (! null_value && (tmp || (tmp= (field->cmp(buff) != 0)))) + field->get_image(buff,length,field->charset()); return tmp; } |