>At first you'll get error message if query was not successful.

No error is generated when query returns 0 records.

>If you use Select INTO TABLE then table will be open and active after querying. Try something like that:
>
>SELECT 0
>Select-SQL command
>lSuccess = USED()
>
>This is also right for INTO CURSOR.

A query always creates table/cursor so the check above doesn't provide any usefull info. You should check system variable _TALLY that holds the # of records returned.

>For checking of array existance try:
>
>lSuccess = TYPE("ALEN(ArrayName)") = "N"

No need to do that. You can use _TALLY.