many-many mapping between unique tables

Hi,

I am facing a problem in mapping between two tables containing unique
entries

T1 T2
_________ ________
| x1 | | y1 |
| x2 | | y2 |
| x3 | | y3 |
--------- ---------

x(i) points to 1 or more entries in T2. y(i) points to one or more entries
in T1. How do I store this mapping? I'd cannot use an array due to size
restrictions and inability to extract data easily for furthur processing.

I don't want to put everything into a single table and repeat values in
the 2nd column since these are really huge tables and I cannot increase
overhead by increasing data redundancy.

Is there some way to do something about this?

\Indraneel

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# Indraneel Majumdar ¡ E-mail: indraneel(at)123india(dot)com #
# Bioinformatics Unit (EMBNET node), ¡ URL: http://scorpius.iwarp.com #
# Centre for DNA Fingerprinting and Diagnostics, #
# Hyderabad, India - 500076 #
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