Thanks for clarifying Sergey - good answer!

>There's one bit reserved per NULL column per record. With 9 NULL columns you get 9 bits or two bytes.
>
>>

>>CREATE CURSOR temp ( ;
>>  c1 C(1) NULL ,;
>>  c2 C(1) NULL ,;
>>  c3 C(1) NULL ,;
>>  c4 c(1) NULL ,;
>>  c5 C(1) NULL ,;
>>  c6 C(1) NULL ,;
>>  c7 c(1) NULL ,;
>>  c8 c(1) NULL  ;
>>)
>>LIST stru
>>

>>
>>Total record length is 10 bytes (1 for delete, 1 for NULL)
>>
>>

>>CREATE CURSOR temp2 ( ;
>>  c1 C(1) NULL ,;
>>  c2 C(1) NULL ,;
>>  c3 C(1) NULL ,;
>>  c4 c(1) NULL ,;
>>  c5 C(1) NULL ,;
>>  c6 C(1) NULL ,;
>>  c7 c(1) NULL ,;
>>  c8 c(1) NULL ,;
>>  c9 c(1) NULL ;
>>)
>>LIST stru	
>>

>>
>>Added just one more column and instead of 11 bytes (9 + 1 for delete + 1 for NULL) it returns 12. Why? What is up with the extra byte?