Posted by Ed Murphy on 10/18/06 02:04

paulmac106@gmail.com wrote:

> So, having said that, I'm really curious as to who "we" are that you
> reference in your original post. And where can I go to get information
> on things like "ISO-11179 rules for data elements names" or another
> site to fix my mindset?

Googling "ISO-11179" turns up http://metadata-standards.org/11179/
and in particular http://metadata-standards.org/11179/#11179-5

"Part 5: Naming and Identification Principles, provides guidance for the
identification of administered items. Identification is a broad term
for designating, or identifying, a particular data item. Identification
can be accomplished in various ways, depending upon the use of the
identifier. Identification includes the assignment of numerical
identifiers that have no inherent meanings to humans; icons (graphic
symbols to which meaning has been assigned); and names with embedded
meaning, usually for human understanding, that are associated with the
data item's definition and value domain."

> btw, Boolean is right there in online books
>
> Searched CASE function:
>
> CASE
> WHEN Boolean_expression THEN result_expression
> [ ...n ]
> [
> ELSE else_result_expression
> ]
> END

That's an expression, not a store-able data type. Again, Googling
(SQL "Boolean type") turns up http://troels.arvin.dk/db/rdbms/
and in particular http://troels.arvin.dk/db/rdbms/#data_types-boolean

Standard:

"The BOOLEAN type is optional (has feature ID T031), which is a bit
surprising for such a basic type. However, it seems that endless
discussions of how NULL is to be interpreted for a boolean value is
holding BOOLEAN from becoming a core type.

The standard says that a BOOLEAN may be one of the following literals:

* TRUE
* FALSE
* UNKNOWN or NULL (unless prohibited by a NOT NULL constraint)

The DBMS may interpret NULL as equivalent to UNKNOWN. It is unclear
from the specification if the DBMS must support UNKNOWN, NULL or both
as boolean literals. In this author's opinion, you should forget about
the UNKNOWN literal in order to simplify the situation and let the
normal SQL three-way logic apply.

It's defined that TRUE > FALSE (true larger than false)."

MSSQL:

"Doesn't support the BOOLEAN type.

Possible alternative type: the BIT type which may have 0 or 1 (or NULL)
as value. If you insert an integer value other than these into a field
of type BIT, then the inserted value will silently be converted to 1.

Rudy Limeback has some notes
[http://searchoracle.techtarget.com/ateQuestionNResponse/
0,289625,sid41_cid556536_tax301455,00.html]
about oddities with the MSSQL BIT type.

Documentation [http://msdn2.microsoft.com/en-us/library/ms177603.aspx]"

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