I have 100K+ lat/longs in a SQL database, and I want to plot them on a google map. The user will input an address to find points close to that address. How should I do this? I have the map working, with the ability for the user to enter an address and have the map center on this point. Just need to add the pins.
I'll be building the front end in JS, and any backend needs in PHP.
Lets start with the search for address, I would use the Google places API. This will allow you to localise your results and get the coordinates of the place in question.
Once you have the coordinates I would head off to the server to do a lookup, if you are using MySQL you can use their spatial extensions which have some handy ways of indexing things spatially.
You say you have 100k items, obv there is NO way that you can send all of them to the frontend to display on the map, you will need to limit your result set or else the users browers will cry tears of blood as it tries to render and handle all of them. You can have a look at the Google Maps Marker Clusterer for a nice way of displaying a high density of markers.