[Haskelldb-users] data structures over tables

[Frederik E. <fre...@a5...>]

Hi,

This question is only partly about haskelldb.

I'm thinking about implementing special indexing data structures over
SQL tables in databases that might not support those structures
natively, for instance an R-tree for multidimensional range queries (I
think mysql supports only up to dimension 2) or a simple balanced tree
for fast calculation of a running total of a given column. (data
structure links would be to primary key columns of tables)

I thought that haskelldb might be a good candidate for such an
implementation because of the ability to achieve modularity by
composing query functions, and also the potential to minimize context
switches by sending large chunks of SQL code to the server at once...
But presumably the datatypes would require atomicity in the form of
locking or transactions, which haskelldb would have to support, as
well as 'if' statements or 'if' functions for logic. An alternative
would be to write stored procedures directly in SQL. (can haskelldb
generate these?) A separate issue is enforcing type constraints, such
as saying that an 'id' value in a certain column can only be used to
look up elements of certain other columns, it seems like it could be a
capability of haskelldb, is it?

Anyway, it seems like a promising use for SQL to me - implement
complex large data structures in a portable way - but I've found very
few relatively unhelpful references to it on the web, partly because I
don't know a search term which doesn't select lots of pages with
information on data structures used internally by sql databases. So if
anybody has any suggestions or pointers I'd be interested. Thanks,

Frederik

-- 
http://ofb.net/~frederik/