Search and Replace

I apologize for having to resort to sending what is most likely a simple
tech support question regarding PostgreSQL to this list but I have not
been able to find the answer in the documentation.

I am responsible for managing a database containing over 6,000 records of
US Forest Service Research publications
(http://www.srs.fs.usda.gov/pubs/search.jsp) and I need to do a simple
search and replace in one of the columns. In these records we have a
field for URLs of the location the research publications and I need to
change the base URL from www.srs.fs.fed.us to www.srs.fs.usda.gov. It
seems like this "search and replace" would be a simple thing to do with an
UPDATE command but I am having great difficulty making this work.

The table definition I am trying to update is: url. At first I thought
about using a simple UPDATE command like this:

UPDATE publications SET url = 'www.srs.fs.usda.gov' WHERE url =
'www.srs.fs.fed.us';

Of course that would work fine but "www.srs.fs.fed.us" is only part of a
complete URL such as: http://www.srs.fs.fed.us/pubs/rp/rp_se263.pdf. My
problem (among other things!) is that I don't know how to pass along
wildcards so that I do not change the other parts of the complete URL. I
have tried substituting "like" for "=" and trying to use the wildcard of
"%" but to no avail. I am really just guessing here.

Any help would be greatly appreciated!

Best,

--rdm

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Randy D. McCracken (0>
Web Guy //\
Communications Group V_/_

USDA/FS - Southern Research Station

E-Mail: rdm(at)srs(dot)fs(dot)usda(dot)gov
Voice: (828) 259-0518
Fax: (828) 257-4840
Web: http://www.srs.fs.fed.us/
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