Comments on: Natural Order Numerical Sorting

By: Robbie

Robbie — Fri, 18 Jul 2008 11:18:57 +0000

The right maximum level query is:

“SELECT max(level) FROM test”

Where:

1 -> level = 0
1.1 -> level = 1
1.1.1 -> level = 2

and so on

By: Robbie

Robbie — Fri, 18 Jul 2008 10:37:39 +0000

The previous doesn’t work, sorry.

I tested this, and it is work fine:

$c = ($m + 1); //$m = max of level -> $query = “SELECT max(version) FROM test”

$queryStr = “Round(SUBSTRING_INDEX(version,’.',1))”;

for ($i = 2; $i < ($c + 1); $i++) {
$queryStr .= “, Round(RIGHT(SUBSTRING_INDEX(version,’.',”.$i.”),((LENGTH(SUBSTRING_INDEX(version,’.',”.$i.”))-1)-LENGTH(SUBSTRING_INDEX(version,’.',”.($i-1).”)))))”;
}

$query = “SELECT version FROM test ORDER BY $queryStr ASC”;

By: Robbie

Robbie — Fri, 18 Jul 2008 07:33:45 +0000

Try this:

SELECT version FROM test ORDER BY (REPLACE(version , ‘.’, ”) ASC

By: Tony

Tony — Thu, 03 Jul 2008 04:27:48 +0000

Thank you.

By: Sean Murphy

Sean Murphy — Fri, 27 Jun 2008 22:11:10 +0000

Robert, unfortunately the technique I outlined only works for two decimals. For each decimal you add the ORDER BY clause must get more and more complex.

By: Robert

Robert — Fri, 27 Jun 2008 18:58:27 +0000

Its very interesting but it didnt work for me. | 2.1.0.135 | 2.1 | | 2.1.0.134 | 2.1 | | 2.1.0.133 | 2.1 | | 2.1.0.132 | 2.1 | | 2.1.0.131 | 2.1 | | 2.1.0.130 | 2.1 | | 2.1.0.13 | 2.1 | <<<<<<< | 2.1.0.129 | 2.1 | | 2.1.0.128 | 2.1 | | 2.1.0.127 | 2.1 | | 2.1.0.126 | 2.1 | | 2.1.0.126 | 2.1 | | 2.1.0.126 | 2.1 | | 2.1.0.126 | 2.1 |

By: Ben Van Aerde

Ben Van Aerde — Thu, 15 May 2008 08:23:24 +0000

Many thanks for this tip!
In addition to the howto: it also works when using other characters than a dot. For example: I used dashes, and it still sorted correctly.