sql injections

gistfile1.txt

This query works,

Model.where("major #{operator} :major OR (major = :major AND minor #{operator} :minor)", :major => major, :minor => minor)

but I am worried about sql injection passing an escaped string

so I tried this

`Model.where("major :operator :major OR (major = :major AND minor :operator :minor)", :major => major, :minor => minor, :operator => :operator)` 

which will throw an error 

 `ERROR:  syntax error at or near "1"
LINE 1: ...o_content_view_versions"  WHERE (major '=' 1 OR (majo...
`

it has an issue with = or > as a string