I need to save custom data(Work order related data) into sales force database. I need to have a service for this the same will be called in my SOA application. What database API i have to use to store my data into Salesforce database.
You can use built in standard Rest services from salesforce to create records in salesforce. These services has support for CRUD operations. You can follow below document. https://developer.salesforce.com/docs/atlas.en-us.api_rest.meta/api_rest/dome_sobject_create.htm