Client applications can perform database operations by sending requests to Web services that offer those operations. The requests are messages that are in one of the following six protocols:
This message protocol is not supported in some products.
For example, suppose that a client application requests a Web service to insert a row into the EMPLOYEE table of the DB2® SAMPLE database. The data types of the columns in the EMPLOYEE table are as follow:
Name of column | Data type |
---|---|
EMPNO | integer |
LASTNAME | varchar |
FIRSTNME | varchar |
SKILLS | XML |
This table lists the values in the new row to insert:
Name of column | Value |
---|---|
EMPNO | 200170 |
LASTNAME | Yamamoto |
FIRSTNME | Kiyoshi |
SKILLS | <skills> <languages> <language name="Japanese" native="yes" level="excellent"/> <language name="English" native="no" level="good"/> </languages> <softskills> <skill name="team leadership" level="good"/> <skill name="presentation" level="medium"/> </softskills> </skills> |
This is the operation that is defined in the Web service:
INSERT INTO employee values (:empno, :lastname, :firstnme, :skills)
Here is an example of the message that a client application could send using the SOAP/HTTP protocol.
POST /Sample/services/Sample HTTP/1.1 Host: localhost:8070 Content-Type: text/xml; charset=utf-8 Content-Length: 704 Accept: application/soap+xml, application/dime, multipart/related, text/* User-Agent: IBM Web Services Explorer Cache-Control: no-cache Pragma: no-cache SOAPAction: "http://www.example.org/insertEmployee" Connection: close <soapenv:Envelope xmlns:q0="http://www.example.org" xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"> <soapenv:Body> <q0:insertEmployee> <empno>200170</empno> <name>Yamamoto</name> <firstname>Kiyoshi</firstname> <skills> <skills> <languages> <language level="excellent" name="Japanese" native="yes"/> <language level="good" name="English" native="no"/> </languages> <softskills> <skill level="good" name="team leadership"/> <skill level="medium" name="presentation"/> </softskills> </skills> </skills> </q0:insertEmployee> </soapenv:Body> </soapenv:Envelope>
Here are examples of the REST-like messages that a client application could send. The messages follow the REST format, but they do not behave like normal REST messages because they do not directly access a data entity. Instead, they perform functions. For example, messages in the GET format do not request a copy of a resource. Also, messages in the POST format do not necessarily add information to a resource. Instead, both GET and POST messages that client applications send are requests to perform operations on data in a database.
In REST-like messages, null values are treated differently for XML-based requests and non-XML requests. In XML-based requests, null values are represented by adding xsi:nil="true" to the parameter element. In non-XML requests, null values are represented as absent; that is, the parameter name does not appear in the parameter or value list.
GET /Sample/RestEndpoint/Sample/insertEmployee?empno=200170&name;=Yamamoto&firstname;=Kiyoshi&skills;=%3Cskills%3E%0D%0A%3Clanguages%3E%0D%0A++ %3Clanguage+level%3D%22very+good%22+name%3D%22Japanese%22+native%3D%22yes%22%2F%3E%0D%0A++%3Clanguage+level%3D%22good%22+name%3D%22English%22+ native%3D%22no%22%2F%3E%0D%0A%3C%2Flanguages%3E%0D%0A%3Csoftskills%3E%0D%0A++%3Cskill+level%3D%22good%22+name%3D%22team+leadership%22%2F%3E% 0D%0A++%3Cskill+level%3D%22medium%22+name%3D%22presentation%22%2F%3E%0D%0A%3C%2Fsoftskills%3E%0D%0A%3C%2Fskills%3E%0D%0A HTTP/1.1 User-Agent: Java/1.5.0 Host: localhost:8070 Accept: text/html, image/gif, image/jpeg, *; q=.2, */*; q=.2 Connection: keep-alive Content-type: application/x-www-form-urlencoded
http://server:port_number/Sample/RestEndpoint/Sample/insertEmployee?empno=200170&name;=Yamamoto&firstname;=Kiyoshi&skills;=%3Cskills%3E%0D%0A%3Clanguages%3E%0D%0A++ %3Clanguage+level%3D%22very+good%22+name%3D%22Japanese%22+native%3D%22yes%22%2F%3E%0D%0A++%3Clanguage+level%3D%22good%22+name%3D%22English%22+ native%3D%22no%22%2F%3E%0D%0A%3C%2Flanguages%3E%0D%0A%3Csoftskills%3E%0D%0A++%3Cskill+level%3D%22good%22+name%3D%22team+leadership%22%2F%3E% 0D%0A++%3Cskill+level%3D%22medium%22+name%3D%22presentation%22%2F%3E%0D%0A%3C%2Fsoftskills%3E%0D%0A%3C%2Fskills%3E%0D%0AThe URL must use UTF-8 characters and conform to the RPC 2396 standard.
POST /Sample/RestEndpoint/Sample/insertEmployee HTTP/1.1 User-Agent: Java/1.5.0 Host: localhost:8070 Accept: text/html, image/gif, image/jpeg, *; q=.2, */*; q=.2 Connection: keep-alive Content-type: application/x-www-form-urlencoded Content-Length: 485 empno=200170&name;=Yamamoto&firstname;=Kiyoshi&skills;=%3Cskills%3E%0D%0A%3Clanguages%3E%0D%0A++%3Clanguage+level%3D%22very+good%22+name%3D%22Japanese%22+ native%3D%22yes%22%2F%3E%0D%0A++%3Clanguage+level%3D%22good%22+name%3D%22English%22+native%3D%22no%22%2F%3E%0D%0A%3C%2Flanguages%3E%0D%0A%3Csof tskills%3E%0D%0A++%3Cskill+level%3D%22good%22+name%3D%22team+leadership%22%2F%3E%0D%0A++%3Cskill+level%3D%22medium%22+name%3D%22presentation%2 2%2F%3E%0D%0A%3C%2Fsoftskills%3E%0D%0A%3C%2Fskills%3E%0D%0A
POST /Sample/RestEndpoint/Sample/insertEmployee HTTP/1.1 Content-Type: text/xml; charset=utf-8 User-Agent: Michael Accept: text/xml, application/dime, multipart/related, text/* Content-Length: 467 Host: localhost:8070 Connection: keep-alive <q0:insertEmployee xmlns:q0="http://www.example.org"><empno>200170</empno><name>Yamamoto</name><firstname>Kiyoshi</firstname><skills><skills> <languages> <language name="Japanese" native="yes" level="excellent"/> <language name="English" native="no" level="good"/> </languages> <softskills> <skill name="team leadership" level="good"/> <skill name="presentation" level="medium"/> </softskills> </skills></skills></q0:insertEmployee>
POST /Project1WebService1/rest/WebService1/insertEmployee HTTP/1.1 Host: localhost:8000 User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9.0.3) Gecko/2008092417 Firefox/3.0.3 Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8 Connection: keep-alive Content-Type: application/json;charset=utf-8 Content-Length: 395 {"insertEmployee":{"EMPNO":200170,"LASTNAME":"Yamamoto","FIRSTNME":"Kiyoshi","SKILLS":"<skills> <languages> <language name=\"Japanese\" native=\"yes\" level=\"excellent\"\/> <language name=\"English\" native=\"no\" level=\"good\"\/> <\/languages> <softskills> <skill name=\"team leadership\" level=\"good\"\/> <skill name=\"presentation\" level=\"medium\"\/> <\/softskills> <\/skills>"}}