I have been learning as much web mapping as possible lately. I really enjoy it, as it seems what you need to know to keep up with the geospatial field. I do have a question that is probably easy for most people to answer.
What is the best way to query/filter/display/symbolize data based on attributes stored on a spatial database and displayed through something like OpenLayers. I know SQL is great for querying data. But how does this fit into the aspect of a web page?? Is this where PHP comes into play? Or Ajax? I am having a lot of trouble desciphering between where the serverside/clientside work ends and begins.
Open layers is great and easy to make maps. But I want to do more with these maps and having trouble what exactly I should learn next in order to actually do something with my data. Can I do all my querying within javascript if something is served through WMS? Can I do basic queries to my GeoJSON files? Or is that where filtering comes in? I saw with CartoDB, they return a url that has the SQL in it. Is this an httpGetRequest? If I have data in MapBox, how can I filter through it and display data based on a attribute, pick from a drop-down box?
Sorry if this is a lot of question. Haha. I am just trying to grasp the concept of how to actually manipulate the data I have displayed on OpenLayers. I understand the differences between the database/map server/APIs and their function. But tying them together in a way which can change how/what/where/when my data displays is whats getting to me. For example, if I want data to be displayed based on an an attribute I type into a box. Where is this work done? Or if I want to find the closest bar to a point I place on the map, what is it on the serverside or clientside that goes through my data and finds this? Thanks!
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What is the best way to query/filter/display/symbolize data based on attributes stored on a spatial database and displayed through something like OpenLayers. I know SQL is great for querying data. But how does this fit into the aspect of a web page?? Is this where PHP comes into play? Or Ajax? I am having a lot of trouble desciphering between where the serverside/clientside work ends and begins.
Open layers is great and easy to make maps. But I want to do more with these maps and having trouble what exactly I should learn next in order to actually do something with my data. Can I do all my querying within javascript if something is served through WMS? Can I do basic queries to my GeoJSON files? Or is that where filtering comes in? I saw with CartoDB, they return a url that has the SQL in it. Is this an httpGetRequest? If I have data in MapBox, how can I filter through it and display data based on a attribute, pick from a drop-down box?
Sorry if this is a lot of question. Haha. I am just trying to grasp the concept of how to actually manipulate the data I have displayed on OpenLayers. I understand the differences between the database/map server/APIs and their function. But tying them together in a way which can change how/what/where/when my data displays is whats getting to me. For example, if I want data to be displayed based on an an attribute I type into a box. Where is this work done? Or if I want to find the closest bar to a point I place on the map, what is it on the serverside or clientside that goes through my data and finds this? Thanks!
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