// POST: odata/Correspondence
        public IHttpActionResult Post(correspondence correspondence)
        {
            if (!ModelState.IsValid)
            {
                return(BadRequest(ModelState));
            }

            db.correspondences.Add(correspondence);

            try
            {
                db.SaveChanges();
            }
            catch (DbUpdateException)
            {
                if (correspondenceExists(correspondence.correspondence_id))
                {
                    return(Conflict());
                }
                else
                {
                    throw;
                }
            }

            return(Created(correspondence));
        }
        // DELETE: odata/Correspondence(5)
        public IHttpActionResult Delete([FromODataUri] int key)
        {
            correspondence correspondence = db.correspondences.Find(key);

            if (correspondence == null)
            {
                return(NotFound());
            }

            db.correspondences.Remove(correspondence);
            db.SaveChanges();

            return(StatusCode(HttpStatusCode.NoContent));
        }
        // PUT: odata/Correspondence(5)
        public IHttpActionResult Put([FromODataUri] int key, Delta <correspondence> patch)
        {
            Validate(patch.GetEntity());

            if (!ModelState.IsValid)
            {
                return(BadRequest(ModelState));
            }

            correspondence correspondence = db.correspondences.Find(key);

            if (correspondence == null)
            {
                return(NotFound());
            }

            patch.Put(correspondence);

            try
            {
                db.SaveChanges();
            }
            catch (DbUpdateConcurrencyException)
            {
                if (!correspondenceExists(key))
                {
                    return(NotFound());
                }
                else
                {
                    throw;
                }
            }

            return(Updated(correspondence));
        }