postgres sql help

<div dir="ltr"> hi, i am fairly new in postgresql, so if anyone can help me would be great<br /><br /> if i simply
do:<br/><br /> select ver_no<br /> from version<br /> order by ver_no<br /><br /> the result will be something like
this:<br/><br /> .1.3.1<br /> .1.3.2.5.<br /> .1.4.1.7.12<br /> .1.4.11.14.7.<br /> .1.4.3.109.1.<br /> .1.4.8.66.<br
/><br/> so as you can see first 3 lines are ok, but how to make 1.4.3.109 come before 1.4.11 because the third level
"3"is smaller than "11". i understand they are stored as char so i used split_part function to separate each numbers
between"." in a separate column. but when i try to convert those column into integer, i am getting an error msg saying:
ERROR:invalid input syntax for type numeric: " "<br /><br /> here is my code:<br /><br /> select ver_no, duedate,
status,<br/> to_number(split_part(ver_no, '.', 2), '9999') a,<br /> to_number(split_part(ver_no, '.', 3), '9999') b,<br
/>to_number(split_part(ver_no, '.', 4), '9999') c,<br /> to_number(split_part(ver_no, '.', 5), '9999') d<br /><br /><br
/>from version<br /><br /> order by a,b,c,d<br /><br /> I am not sure if i am heading towards wrong direction but can
someoneplease suggest or give me some other ideas to sort this. <br /><br /> PS: i found some good solution in SQL
Serverbut those commands are not used in postgreSQL.<br /><br />Thanks in advance<br /><br />- James<br /><br /></div>