I'm selecting and styling my points layer on a contour map of Philadelphia using Rules Based Styling. (see: https://gis.stackexchange.com/questions/53346/can-i-use-rules-based-rendering-in-qgis-to-select-features). The filtering process using [string_field = 'string'] turns out not to be accurate for one of my three rules. I have 'Homocide - Justifiable' and it returns points with (at least) 'Thefts'.
I'd like to try another expression. In any case it would be nice to have a list of all the possible expressions.