Tables > Data table formats > Numerics, NULLs > Numerics/NULLs in dBASE apps

Numerics and NULLs in traditional dBASE applications

About entering NUMERICs and FLOATs, as well as the handling of numeric and logical NULL values.

NUMERICs and NULL

In some traditional dBASE applications entering e.g. 12345,678 into a NUMERIC(7,3) or a FLOAT(7,3) field the entered digits may end up as 123,678 ignoring the 4th and 5th integer until pressing the decimal separator, however usually with an audible warning.

And entering e.g. 12345,678 into a NUMERIC(5,3) or FLOAT(5,3) field the entered digits may end up as 1,6.

Values entered by other applications and for numeric fields sized as e.g. NUMERIC(7,3) and holding numbers with more than 3 integers may display as row of asterisk without any clue of the actual stored values.

For dBASE level III+, IV and 5 numeric fields without entered values may display as zeros (with or without decimal separator).

Only with dBASE 7 tables the non-filled numerics usually display empty.

LOGICALs and NULL

For LOGICAL fields, displaying as a check box may display either checked or unchecked.
Be careful depending on NULLs for LOGICAL fields with dBASE tables, as many dBASE applications traditionally do not distinguish between FALSE and NULL.
See also NULL values and Check Box Logicals.

Rounding up

Many dBASE applications have been serving with huge potentials by it's comprehensive programming language of it's own, and probably with possible solutions to the issues above, but historically the interface on a table has been a challenge.