The response from a SOAP function is an XML document that contains the SOAP response.

SOAP responses are structured XML documents, so SQL Anywhere, by default, attempts to exploit this information and construct a more useful result set. Each of the top-level tags within the returned response document is extracted and used as a column name. The contents below each of these tags in the subtree is used as the row value for that column.

For example, SQL Anywhere would construct the shown data set given the following SOAP response:

<SOAP-ENV:Envelope
  xmlns:SOAPSDK1="http://www.w3.org/2001/XMLSchema"
  xmlns:SOAPSDK2="http://www.w3.org/2001/XMLSchema-instance"
  xmlns:SOAPSDK3="http://schemas.xmlsoap.org/soap/encoding/"
  xmlns:SOAP-ENV="http://schemas.xmlsoap.org/soap/envelope/">
  <SOAP-ENV:Body>
     <ElizaResponse xmlns:SOAPSDK4="SoapInterop">
        <Eliza>Hi, I'm Eliza. Nice to meet you.</Eliza>
     <ElizaResponse>
  </SOAP-ENV:Body>
</SOAP-ENV:Envelope>

In this example, the response document is delimited by the <ElizaResponse> tags that appear within the <SOAP-ENV:Body> tags.

Result sets have as many columns as there are top-level tags. This result set only has one column because there is only one top-level tag in the SOAP response. This single top-level tag, Eliza, becomes the name of the column.

Information within XML result sets, including SOAP responses, can be accessed using the OPENXML procedure.

The following example uses the OPENXML procedure to extract portions of a SOAP response. This example uses a web service to expose the contents of the SYSWEBSERVICE table as a SOAP service:

CREATE SERVICE get_webservices
    TYPE 'SOAP'
    AUTHORIZATION OFF
    USER DBA
    AS SELECT * FROM SYSWEBSERVICE;

The following web client function, which must be created in a second SQL Anywhere database, issues a call to this web service. The return value of this function is the entire SOAP response document. The response is in the .NET DataSet format because DNET is the default SOAP service format.

CREATE FUNCTION get_webservices()
    RETURNS LONG VARCHAR
    URL 'HTTP://localhost/get_webservices'
    TYPE 'SOAP:DOC';

The following statement illustrates how you can use the OPENXML procedure to extract two columns of the result set. The service_name and secure_required columns indicate which SOAP services are secure and where HTTPS is required.

SELECT *
FROM OPENXML( get_webservices(), '//row' )
WITH ("Name"    CHAR(128) 'service_name',
      "Secure?" CHAR(1)   'secure_required' );

This statement works by selecting the decedents of the row node. The WITH clause constructs the result set based on the two elements of interest. Assuming only the get_webservices web service exists, this function returns the following result set:

• Variables accessed from result sets
• XML in the database
• OPENXML operator