Filter help, string expression

[Steve Lime]

MapServer doesn't handle nulls all that well. Various data drivers do
things differently
which complicates things. For example, for some NULL means an empty
string.

Anyway, you might try something like this instead:

FILTERITEM "FENAME"
FILTER /./

This tests to see if there is at least one character in the FENAME
attribute. It should
evaluate faster too.

Steve

>>> Scott Schulthess <scott at TOPOZONE.COM> 2/20/2007 1:14:16 PM >>>
I'm trying to use the filter command in my mapfile make mapserver not
draw a street if one of it's attributes (the street name) is null.

 

I have tried using this

 

FILTER ("[FENAME]" != "(NULL)")

 

That's what it looks like in the dbf file - (NULL) when there is no
name. However it just doesn't draw anything for that layer.  

 

Here's the layer definition and one class

 

  LAYER

    METADATA

                        "wms_srs"       wmsEPSGNAD83

            END     

    NAME "US Streets"

            GROUP US_POINTLINE

    STATUS OFF

    DATA "str"

            PROJECTION

      "init=epsg:4326"

    END

    TILEINDEX "us_streets/county_index"

    TILEITEM "location"

    TYPE LINE

    SIZEUNITS PIXELS    

            TRANSPARENCY ALPHA //test

            FILTER ("[FENAME]" != "(NULL)")

            CLASS

      NAME "US Streets"

      MINSCALE  99001

      MAXSCALE 190000

      STYLE

        SYMBOL "circle"

        COLOR 183 176 169

                        SIZE 4

                        ANTIALIAS TRUE

      END

      STYLE

        SYMBOL "circle"

        COLOR 254 254 254

                        SIZE 2

                        ANTIALIAS TRUE 

      END

    END

 

Tips?

 

-Scott