Using AWK to treat files

Question

I have something to do that must be finished before 4.00PM.

I want to create a batch file with awk, grep or sed that keeps all lines beginning with 'INSERT' and deletes the other lines.

After this, I want to replace a string "change)" by "servicechange)" when the 3rd word in the treated line is "donextsit".

Please explain how to do this.

Answer 1

awk '/INSERT/{ 
    if ($3=="donextsit"){
       gsub("change","servicechange");
       print
    }
}' file

since this is homework, something is still not working..you should find out for yourself

Answer 2

sed '
    /^INSERT/ ! d;
    /^ *[^ ]\+ *[^ ]\+ *donextsit / s/change)/servicechange)/g;
' -i file

Edit: Incorporated Jonathan Leffler's suggestions. Thx.

Answer 3

Thx to edgar.holleis and ghostdog74.
It seems good ideas but i have some problems again. :(
I want to put the result in a file. How to do this? I think it's the "print" command that may be replaced by something else. Who can help me?