[BioSQL-l] Rank terms

[Hilmar Lapp]

Basically counters, e.g. index in an array, or any other number 
introducing an ordering.

They were originally nullable, but we made all rank columns NOT NULL 
that take part in a unique key constraint in order to get correct and 
consistent behaviour from all supported RDBMS platforms (MySQL was 
giving problems due to its deviant treatment of null columns in 
compound keys).

	-hilmar

On Jan 26, 2005, at 1:42 AM, mark.schreiber at group.novartis.com wrote:

> Several tables have 'rank' columns which in some cases are not 
> nullable.
> What are they for?
>
> - Mark
>
> Mark Schreiber
> Principal Scientist (Bioinformatics)
>
> Novartis Institute for Tropical Diseases (NITD)
> 10 Biopolis Road
> #05-01 Chromos
> Singapore 138670
> www.nitd.novartis.com
>
> phone +65 6722 2973
> fax  +65 6722 2910
>
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-- 
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Hilmar Lapp                            email: lapp at gnf.org
GNF, San Diego, Ca. 92121              phone: +1-858-812-1757
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