Re: BUG #18560: Inconsistent Behavior of PostgreSQL 'LIKE' Operator

Aleksander Alekseev <aleksander@timescale.com>

From: Aleksander Alekseev <aleksander@timescale.com>
To: pgsql-bugs@lists.postgresql.org
Cc: ammmkilo@163.com
Date: 2024-07-31T09:19:59Z
Lists: pgsql-bugs
Hi,

> In sql1, the result of the (" like ") query returns true. In sql2 (c1 like
> c1) the return value is false when c1 is ".
> I think this is contradictory and there may be some bug between the 'like'
> and the query column.

Actually the result is consistent:

```
SELECT c1, c1 = ' ' FROM t0;
 c1 | ?column?
----+----------
 1  | f
    | t
(2 rows)

select ' '::char(1) like ' '::char(1);
 ?column?
----------
 f
(1 row)
```

Although I find it puzzling too that LIKE operators for CHAR(1) and
TEXT work differently. Not 100% sure if this is intended.

Thoughts?

-- 
Best regards,
Aleksander Alekseev