Select Single Statement

Hi,

I am using Select Single Statement inside a Loop for Validating , is there any problem regarding Performace.

Loop at itb_file_input into wa_itb_file_input.

......

.......

.......

......

.......

SELECT SINGLE varbl

FROM agr_1252

INTO v_varbl

WHERE agr_name EQ wa_itb_file_input-child

AND varbl EQ wa_itb_file_input-orgname.

.....

....

Endloop.

<i>Thanks .</i>Avi.............