BLANK(<exp>)
Evaluates an empty value of any data type expression.
Returns the empty value of <exp>.
<exp> can be any valid data type, or a specifically defined
character data type as defined below.
Type Returns Note
════ ═══════ ════════════════════════════════════════
L .F. logical type
N 0.00 numeric type
D ' / / ' date type
C "..." char type: LEN(<expC>) blank spaces
C " : : " 8 byte, 6 digit time string
C " - " 11 byte, 10 digit zip code
C "( ) - " 13 byte, 10 digit telephone
C " - - " 11 byte, 9 digit social security number
Returns unchanged <expC> if not enough memory to allocate for the
blank return string of a long character-type expression
* Examples assume an open database file.
* To permanently delete a record.
REPLACE Last_name WITH BLANK( Last_name ),;
First_name WITH BLANK( First_name ),;
Address WITH BLANK( Address )
* To reuse deleted records
SEEK BLANK( Last_name ) && find empty key field
IF .NOT. FOUND()
APPEND BLANK
ENDIF
Useful with REPLACE as a self-maintaining delete algorithm.
Replacing all fields with blanks means never having to PACK
your database file. Simply re-use the blank records before
appending a new blank record as in the last example.
Placed in the Public Domain by Tom Rettig Assoc.