SQL statement Problem

     Can someone tell me why I can execute this SQL statement:

     apps>select * from tbl_rdevices
     apps>\g
     and get results, but when I execute

     ------

     apps=> select * from tbl_rdevices
     apps-> where asset = '05227'
     apps-> \g
     ERROR:  attribute 'asset' not found
     apps=>

     ------

     apps=> select asset, equipmentnumber
     apps-> from tbl_rdevices
     apps-> \g
     ERROR:  attribute 'asset' not found
     apps=>

     -----

     the attribute 'asset' not found means?


     Could some Please let me know what I'm doing wrong.
     Using RedHat 5.1
           postgresql-6.3.2-4


     Chauncey THorn