Bug #41703 Falcon: dagger duplicates space

• Submitted: 23 Dec 2008 0:56
• Modified: 23 Dec 2008 15:31
• Reporter: Peter Gulutzan
• Status: Duplicate
• Category: MySQL Server: Falcon storage engine
• Severity: S2 (Serious)
• Version: 6.0.10-alpha-debug
• OS: Any
• Assigned to: Assigned Account
• CPU Architecture: Any
• Tags: F_ENCODING

[23 Dec 2008 0:56] Peter Gulutzan

Description:
I create a Falcon table with a CHAR() primary key.
I insert a dagger.
I insert a space.
I see a 'duplicate primary key' message.

I'm sure I've seen it before, but can't find an earlier bug report.

How to repeat:
create table t1 (s1 char(4) character set ucs2 primary key) engine=falcon;
insert into t1 values (0x2020);
insert into t1 values ('');
/* Result: ERROR 1062 (23000): Duplicate entry '' for key 'PRIMARY' */

[23 Dec 2008 1:00] Hakan Küçükyılmaz

Peter, your example looks like an empty string. Do you mean space (0x20) or an empty character?

[23 Dec 2008 1:02] Hakan Küçükyılmaz

[02:01] root@test>create table t1 (s1 char(4) character set ucs2 primary key) engine=falcon;
Query OK, 0 rows affected (0.00 sec)

[02:01] root@test>insert into t1 values (0x2020);
Query OK, 1 row affected (0.00 sec)

[02:01] root@test>insert into t1 values ('');
ERROR 1062 (23000): Duplicate entry '' for key 'PRIMARY'

[02:01] root@test>insert into t1 values (' ');
ERROR 1062 (23000): Duplicate entry '' for key 'PRIMARY'

[23 Dec 2008 15:31] Ann Harrison

This is a duplicate of 34479

Note that this is UCS2.  We've got an untamed tendency to chop off
dangling 0x20 bytes from strings that needs to be adjusted for fixed
size multi-byte characters.  

create table t1 (s1 char(4) 
                 character set ucs2 primary key)
                 engine=falcon;
insert into t1 values (0x2020);
insert into t1 values ('');

When using UCS2 we can truncate trailing blanks which are two bytes, not
trailing 0x20 bytes.