Update entire column with new date values

Hi all,

I have a simple table which contains information about our safety files:

CREATE TABLE docs
(
filename varchar(256) NOT NULL,
filepath varchar(256) NOT NULL,
version varchar(8),
date timestamp NOT NULL,
docid int8 NOT NULL DEFAULT nextval('docs_docid_seq'::regclass),
category varchar(16), NOT NULL
CONSTRAINT pkey_docs PRIMARY KEY (docid, filename, date),
CONSTRAINT ukey_docid UNIQUE (docid)
)

I need to update the date for each file (the "date" & "filename"
columns). However, the updated values for date are not the same for each
file (due to when the files were last modified). I can import the new
date values from a text file containing the date and filename.

What sort of "UPDATE" command do I use in this case? Essentially, I'm
trying to do something like:

UPDATE docs SET date = '{$input_date}'
FROM ('C:/Temp/docupdate.txt')
WHERE filename = '{$input_filename}';

Any help is appreciated. Thanks!

Kevin Weiss
kevin(dot)weiss(at)selkirkinc(dot)com