Here in this tutorial, I am going to discuss query() and queryMore() operations in salesforce and how to invoke the same in a BPEL.

In my previous tutorials I have already discussed interaction with salesforce API using enterprise wsdl. Please refer those if you are new to use cases where salesforce has to be invoked directly.

I came across a scenario where I needed to retrieve data from a salesforce object. Query operation is a very easy way to do the same. Just a select query on the object and that is all. Please note that * is not used in sql query here. Specify all necessary field names that you want.

The query result object contains up to 500 rows of data by default. If the query results exceed 500 rows, then the client application uses the queryMore() call and a server-side cursor to retrieve additional rows in 500-row chunks.Moreover if you are querying for fields of type Base64, both query and query more returns a single record.

query()

Executes a query against the specified object and returns data that matches the specified criteria.

query() call is used to retrieve data from an object and below are the parameters

INPUT-

1) queryString a query expression that specifies the object to query, the fields to retrieve, and any conditions that determine whether a given object qualifies.

Upon invocation, the API executes the query against the specified object, caches the results of the query on the API, and returns a query response object to the client application

OUTPUT-

1) done

type- Boolean

value-(true/false)

Description- Indicates whether additional rows need to be retrieved from the query results (false) using queryMore(), or not (true). Your client application can use this value as a loop condition while iterating through the query results.

2) queryLocator

Description- A specialized string, similar to ID. Used in queryMore() for retrieving subsequent sets of objects from the query results, if applicable.

3) Records

Type- sObjects []

Description- Array of sObjects representing individual objects of the specified object and containing data defined in the field list specified in the queryString

4) Size

Type- int

Description-Total number of rows retrieved in the query.

queryMore()

Retrieves the next batch of objects from a query()

INPUT-

1) queryLocator

OUTPUT-

Is same as that of query() operation.

Steps.

1) Create a SOA project with a BPEL and a reference with salesforce enterprise wsdl.

2) Invoke login operation and assign username and password

use session id, URL retrieved as response of login operation in subsequent operations as discussed in previous tutorials

3) Invoke query operation and create input and output variables. Input and Output of query operation looks like below

4) Assign sql query as input to query() operation

5) Create variables done,QueryLocator as string. Assign done and QueryLocator returned as response of query() operation to these variables.

6) Drop a While activity and enter the condition as done='false'.

7) Inside the while loop drop Invoke activity for queryMore operation and create input and output variables. Input and Output of query operation looks like below.