Are WALs affected by 'duplicate key' errors?

A grim suspicion begins to dawn on me ...

We have an application that attempts many insertions into a table,
detecting the prior existance of the row by whether we get a 'duplicate
key in unique index' error.  When this application is running as multiple
copies and really cranking, we get 130K or more of these in a day.  Are
these filling up (and possibly messing up) our WALs?  We have experienced
a few shared-memory corruption errors, and a full-blown corruption
(although of a different table).


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Jeff Boes                                             vox 616.226.9550
Database Engineer                                     fax 616.349.9076
Nexcerpt, Inc.                                      jboes@nexcerpt.com