loop and read statements

hi all,

I am getting more than 75000 records in one table. I have to concatenate 3 fields from it into one variable, for all entries and then use that variable to fetch another table. I  have to do this for all possible values of that variable.

So which statement should I used to get values from internal table into work area if there are more than 75000 records. LOOP statement or READ statement.?

thanks,

Hrishikesh V.