How do I get Flex to query my database

Question :How do I get Flex to query my database?
Answer :Flex does not have any native database integration functionality. You must have your own server-side
tier that provides the database-access tier and sends the data back to Flex through one of the
following protocols:
•RemoteObjects: This is the fastest. It communicates with server-side EJBs or POJOs using
AMF, a binary compressed format.
•HTTPService: This one uses the HTTP protocol. Sources can be JSP, ASPx, .NET, or any
URL that returns HTTP.
•WebService: This is the slowest. It uses the SOAP protocol. Sources can be .NET or any web
service.