diff options
Diffstat (limited to 'sql/ha_federated.cc')
| -rw-r--r-- | sql/ha_federated.cc | 22 |
1 files changed, 19 insertions, 3 deletions
diff --git a/sql/ha_federated.cc b/sql/ha_federated.cc index ac1e0962ffb..c0743bd6c9a 100644 --- a/sql/ha_federated.cc +++ b/sql/ha_federated.cc @@ -1094,10 +1094,20 @@ bool ha_federated::create_where_from_key(String *to, { if (*ptr++) { + /* + We got "IS [NOT] NULL" condition against nullable column. We + distinguish between "IS NOT NULL" and "IS NULL" by flag. For + "IS NULL", flag is set to HA_READ_KEY_EXACT. + */ if (emit_key_part_name(&tmp, key_part) || - tmp.append(FEDERATED_ISNULL)) + tmp.append(ranges[i]->flag == HA_READ_KEY_EXACT ? + FEDERATED_ISNULL : " IS NOT NULL ")) DBUG_RETURN(1); - continue; + /* + We need to adjust pointer and length to be prepared for next + key part. As well as check if this was last key part. + */ + goto prepare_for_next_key_part; } } @@ -1199,12 +1209,18 @@ bool ha_federated::create_where_from_key(String *to, if (tmp.append(FEDERATED_CLOSEPAREN)) DBUG_RETURN(1); +prepare_for_next_key_part: if (store_length >= length) break; DBUG_PRINT("info", ("remainder %d", remainder)); DBUG_ASSERT(remainder > 1); length-= store_length; - ptr+= store_length; + /* + For nullable columns, null-byte is already skipped before, that is + ptr was incremented by 1. Since store_length still counts null-byte, + we need to subtract 1 from store_length. + */ + ptr+= store_length - test(key_part->null_bit); if (tmp.append(FEDERATED_AND)) DBUG_RETURN(1); |