Comparision between two different approach

Hi all ,

Please let me know which of the below will be good in terms of performance :

1. SELECT VBELN ERNAM ERDAT VSTEL KUNNR

FROM LIKP

INTO TABLE I_LIKP

WHERE VSTEL IN S_VSTEL

AND LFART IN S_LFART

AND WADAT_IST = 0.

And

2. CONSTANTS: gc_erdat TYPE erdat VALUE IS INITIAL.

SELECT VBELN ERNAM ERDAT VSTEL KUNNR

FROM LIKP

INTO TABLE I_LIKP

WHERE VSTEL IN S_VSTEL

AND erdat GE gc_erda

AND LFART IN S_LFART

AND WADAT_IST = 0.

Also, provide reason for the same.

Thanks in Advance.

VSTEL , ERDAT And LFART are fields in secondary index.