[SOLVED] use subtring on a table field in the order by clause

[tpra21]

I am trying to reformat a table field of text type from mm-dd-yyyy to yyyy-mm-dd, and then use that field in the ORDER BY clause. The following is what I have got, but the subtring is using the table field's name, not the contents of the field.

 

$query.='ORDER BY '.substr(ad_start,6,4).substr(ad_start,0,2).substr(ad_start,3,2).' ';

 

ad_start is the name of the text field. This ORDER BY clause is resulting in "rtadst"

[tpra21]

Figured it out:

 

$query.='ORDER BY concat(substring(ad_start,7,4),substring(ad_start,0,2),substring(ad_start,3,2)) DESC ';