Gerhardus Geldenhuis wrote:

>The sql error code -804 has four different possible
>meanings. Each of the four messages/meanings
>has a different Interbase Number.

Yup. Not all that clever. In the early days,
of InterBase Software, there was a strong tendency
to compress classes of error into a single primary
message with secondary messages that indicated the
precise cause. We did that to maintain compatibility
with Rdb/VMS - both products had the same major
error codes.

>Questions:
>Why is there two different numbering systems.

The SQL error codes were taken from DB2 in 1985.

>Is the SQLCode a standard like sql?

No.

>If so I
>can see no relation between the 4 posible
>meanings of -804 for example.

They all mean that a data element in the query
was not understood.

>What does ISC stand for.

Interbase Software Corporation. GDS is
Groton Database Systems, one of the early
names for ISC.

>The Interbase number is decidely long.
>Is there a pattern in the number is it
>used to classify error codes. All the
>isc_error codes contains 335544 which
>seems like a waste.

Those are VMS standard error codes - 335544
was the prefix for the relational database
products. VMS had a central error handling
mechanism, so every product had a separate
number space for codes.