Shell Programming and Scripting

Of course not. It's a different structure.

Are you saying that commas are disappearing from the output? If not, what, exactly, is not working?

Did you notice that the commas are connected to the last field in your data sample in post #7 but they were connected to the next to the last field in your data sample in post #1? Did you notice that there is no comma on the last line of your sample input in post #1, but there is a comma on the last line of your sample input in post #7?

What output are you hoping to get from the sample data provided in post #7?

PS Please use CODE tags (not QUOTE tags) when displaying sample input, output, and code segments.

There are some spaces in my first field as well as my delimiter "," and the second field. So I am looking for o/p to be like the one I mentioned.

The trim is disappearing when there are spaces between field 1 and delimiter ","

Try

Code:

awk '$NF ~ "string" {$1 = "trim(" $1 ")"} {$NF = ","}  1' file
Tpc.CALCULATED_AMT as CALCULATED_AMT ,
trim(Tpc.SERVICE_ID) as SERVICE_ID ,
TRC.ITEM_NO as ITEM_NO ,
trim(TPC.LAST_UPD_TIMESTAMP) as LAST_UPD_TIMESTAMP ,

If that does not satisfy you need, please carefully create a reasonable, consistent specification including input and output samples and the logics connecting the two.