database filtering with FILTER or DATA ?

[rich.fromm]

My data is being queried from a postgis database.  The documentation here:
http://mapserver.gis.umn.edu/docs/reference/mapfile/layer

suggests that the DATA directive within LAYER just specifies the column name
and tablename:

--- begin ---
If this is a PostGIS layer, the parameter should be in the form of
"<columnname> from <tablename>", where "columnname" is the name of the
column
containing the geometry objects and "tablename" is the name of the table
from
which the geometry data will be read.
--- end ---

and that any filtering that I want to do of the query is done with the
FILTER
directive within LAYER:

--- begin ---
FILTER [string]

    This parameter allows for data specific attribute filtering that is done
    at the same time spatial filtering is done, but before any CLASS
    expressions are evaluated. For OGR and shapefiles the string is simply a
    mapserver regular expression. For spatial databases the string is a SQL
    WHERE clause that is valid with respect to the underlying database.

    For example: FILTER "type='road' and size <2"
--- end ---

So, for example, I might have something like the following:

--- begin ---
        DATA		"the_geom FROM landuseb"
        FILTER		"the_geom && 'SRID=4326;LINESTRING(-122.3019062479681
37.83351284250283, -122.28009375203187 37.84648658222045)' AND
feat_cod=2000123"
--- end ---


The following post seems to suggest that this is not a good thing to do. 
That
by using FILTER it is mapserver doing the filtering, and not the database. 
It
says to use a more complex DATA expression, including the restricted query. 
I
think it is implying that in this case there is no FILTER expression:

http://www.nabble.com/Variable-Substitution-in-Postgis-Query-to2951829.html#a2951829

Is this really true?  I realize the thread is nearly 2 years old, so things
may have changed.

Furthermore, I tried all sorts of permutations of the expression for DATA to
give me something that effectively executes the following postgis query:

SELECT the_geom FROM landuseb WHERE the_geom &&
'SRID=4326;LINESTRING(-122.3019062479681 37.83351284250283,
-122.28009375203187 37.84648658222045)' AND feat_cod=2000123;

and I couldn't get anything to work.

So if this is a more efficient way to do filtering, any help on the syntax
would also be most appreciated.

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