I would like the best way to tag a library from a large (e.g. 1Mb) textfile consisting of a list of filepath-propertyvalue pairs e.g.
S:\TLIB\07798105810046\1\1.WMA Concierto en la luna S:\TLIB\07798105810046\1\3.WMA Loca bohemia ...
where the filepath is the path of the file that is to have the propertyvalue written to a certain fixed field e.g. Title.
For smaller lists I have imported the entire textfile into the propertyfield and then used string functions to remove all but the matching propertyvalue, but that would be very slow for a 1Mb list.