Little unclear what your scenario is, but if your saying that one column holds a type, say FRUIT_TYPE, and records are being added with additional types of fruit... it was [apples, oranges, grapes] now it's [apples, oranges, grapes, kumquats] you can't on the fly make new layers based on types. If you know the types ahead of time, you can make different layers based on a definition query.
What I think you want to do is symbolize a single layer using the column FRUIT_TYPE in the map document, see "Drawing a layer using categories"
http://help.arcgis.com/en/arcgisdesktop/10.0/help/index.html#/Drawing_a_layer_using_categories/00s50000003m000000/
Then you publish as a ArcGISDynamicMapServiceLayer
If you made a the data a feature class, you could do some dynamic styling in javascript, maybe using a randomized color (or maybe define a long array of colors and pop the next one as needed) based on FRUIT_TYPE.
Then, do some javascript magic with popups or queries or identifytask, see my website for nice identify snippet http://www.spatialexception.org/posts/arcgis-javascript-identifytask-returns-scale-dependent-layers