i want to sort the file based on sortkey:empsal in ascending order. so if i specify sort fields=(15,5, PD, A) or (15,5,BI,A) or (15,5,ZD,A) instead of (15,5,ch,A) will it work? if so whats the difference between these formats?
PD, BI, ZD and CH are different DFSORT formats that correspond to different internal representations of values.
BI is binary format - it can be used to sort unsigned binary values of any type.
CH is character format - it can be used to sort character data.
PD is packed decimal - it can be used to sort signed decimal data in the form X'dd...ds' where d is a digit (0-9) and s is a sign (usually C or F for positive values or D for negative values).
ZD is zoned decimal - it can be used to sort signed decimal data in the form X'zdzd...sd' where z (the zone - usually F) is ignored, d is a digit (0-9) and s is a sign (usually C or F for positive values or D for negative values).
In your case, your salary field is unsigned and contains digits of the form X'Fd'. You can sort this type of data correctly with ZD, CH or BI format.
You cannot sort this type of data correctly with PD format because it is not a PD value. For example, the value X'F3F0F0F0F0' is in the correct X'zdzdzdzdsd' format for ZD, but is not in the correct X'ddddddddds' format for PD (e.g. F is not a 0-9 digit as expected).
Note that values like X'F3F0F0F0F0', X'F5F0F0F0C2' and X'F3F0F0F0D0', etc could be sorted correctly with ZD, but not with CH or BI because of the sign. With ZD format, the F, C and D signs are interpreted correctly, whereas with BI and CH, they aren't.
CH and BI are generally interchangeable for sorting unless you are using a parameter that affects CH but not BI such as CHALT or LOCALE.
For more information on the various formats supported by DFSORT, see: