DECODE file field is required in Bash

Shell Programming and Scripting
1

Dear All,

I want to decode the one of the file field.

Input file:
9393939393|999|2009-02-20 00:00:01|2||4587|2007-02-28 00:00:01|0
9393939393|2001|2009-02-20 00:00:01|2||4587|2007-02-28 00:00:01|0
9393939393|1500|2009-02-20 00:00:01|2||4587| 2007-02-28 00:00:01|0
9393939393|999|2009-02-20 00:00:01|2||4587|2007-02-28 00:00:01| 0
9393939393|1500|2009-02-20 00:00:01|2||4587|2007-02-28 00:00:01|0

Required output file:
9393939393|MRP_25|2009-02-20 00:00:01|2||4587|2007-02-28 00:00:01|0
9393939393|MRP_75|2009-02-20 00:00:01|2||4587|2007-02-28 00:00:01|0
9393939393|MRP_50|2009-02-20 00:00:01|2||4587| 2007-02-28 00:00:01|0
9393939393|MRP_25|2009-02-20 00:00:01|2||4587|2007-02-28 00:00:01| 0
9393939393|MRP_50|2009-02-20 00:00:01|2||4587|2007-02-28 00:00:01|0

Any option is there in UNIX, to decode the field & recreate the new file with the decoded value.

Regards
Hanuma

2 
awk -F"|" '
        $2 == "999"     { sub(/.*/,"MRP-25",$2); print}
        $2 == "1500"    { sub(/.*/,"MRP-50",$2); print}
        $2 == "2001"    { sub(/.*/,"MRP-75",$2); print}
' OFS="|" infile