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@cxxr
Created February 17, 2016 22:01
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PostgreSQL Inconsistent Lexicographic Sort
Run this SQL:
CREATE TEMPORARY TABLE SORTER ( name VARCHAR );
INSERT INTO SORTER (name) VALUES ('A B');
INSERT INTO SORTER (name) VALUES ('AB');
INSERT INTO SORTER (name) VALUES ('A C');
INSERT INTO SORTER (name) VALUES ('AC');
SELECT * FROM SORTER ORDER BY name;
SELECT * FROM SORTER ORDER BY name DESC;
On OSX PostgreSQL 9.4.1:
name
------
A B
A C
AB
AC
(4 rows)
name
------
AC
AB
A C
A B
(4 rows)
On Linux PostgreSQL 9.4.4:
name
------
AB
A B
AC
A C
(4 rows)
name
------
A C
AC
A B
AB
(4 rows)
@decibel
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decibel commented Feb 17, 2016

Confirmed with 9.5.0 on both and client_encoding=SQL_ASCII

I suspect this is due to an underlying library difference, although the OS level sort command seems to do the same thing on both platform.

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