The following bug has been logged online:
Bug reference: 1748
Logged by: Greg Steffensen
Email address: greg(dot)steffensen(at)gmail(dot)com
PostgreSQL version: 8.02
Operating system: Gentoo Linux
Description: Unique contraints cannot be added to long text fields
Details:
I'm storing SVG files, which can be many kilobytes long, in a text field.
When I try to add a unique contraint to that field, or try to add a row to a
table that already has had the unique contraint applied, I get errors like
the following:
ERROR: index row requires 15528 bytes, maximum size is 8191
Evidently, the unique constraint creates an index, but the index can't
handle large field sizes.