Oracle OSB-SOA-BPEL Interview Question and Answer – Part 16

In this article, we will discuss interview question with their justification on Oracle OSB, SOA and BPEL

This is part-16 of Oracle OSB-SOA-BPEL interview question series

Q) What are the operations supported by Database Adapter ?

  • Call a stored procedure/function
  • Perform DML operations on Tables (select, insert, merge, delete, etc)
  • Poll for new/changed record in a Table
  • Execute pure SQL

Figure: Database Operation Type

Q) Explain database polling using Database Adapter ?

While configuring database adapter, there are four main category of database interaction. When we need to poll the database for new/change records, then choose “Poll for new/changed record in a Table”. It will be a SELECT query. And there are 5 supported DML operations to modify/update the read/polled records as mentioned in the above figure

Figure: Database adapter

Q) How to Read a record from a file and insert it in a database ?

  • Create a new SOA App with Web Services Project
  • Create a JCA File Adapter, choose file location, create a XSD schema, generates a WSDL
  • Create a new BPEL 2.0 – one way flow, select the WSDL which has .jca file adapter WSDL
  • Add assign activity to map fields to local fields
  • Create a db adapter, to map local fields values to SQL insert query

Q) Explain file adapter without polling, how could I invoke & get file content ?

  • Use “Synchronous Read File” operation while configuring file adapter && invoke this configured from BPEL flow

Q) How to transfer files from one location to another location using File Adapter (list of files say 10 files) ?

  • Read file as Attachment
  • For Oracle BPEL PM and Mediator, the Oracle File Adapter provides support for transferring large files as attachments
  • To use this feature, select the Read File as Attachment check box in the JDeveloper wizard while configuring the “Read operation
  • This option opaquely transfers a large amount of data from one place to another as attachments
  • For example, you can transfer large MS Word documents, images, and PDFs without processing their content within the composite application

Q) Why we need BPEL process orchestration when same could be achieved using OSB in version 11g ?

  • With BPEL 11g, you can orchestrate services for complex processing & this could be Synchronous/Asynchronous interaction
  • The same orchestration mechanism can be very well achieved/constructed in OSB 11g, but it is stateless

Q) What is BPEL Process in SOA ?

  • BPEL Process is a language used for the composition, orchestration and co-ordination of web services

Q) How can we embed or use a java code in BPEL ?

  • Using JAVA embedding activity in BPEL, Java code can be embedded in BPEL and can be used

Q) What are the BPEL activities ? 

Activities are most useful for BPEL Process all activities are drag and drop to BPEL Service Component BPEL process consist of

BPEL Assign activity: used for to control the data, copy the content one variable to another
BPEL Invoke Activity: used for invoke the services, which identify the partner link and specify the operation
BPEL Receive activity: is used for asynchronous callback response from partner link of service
BPEL Scope Activity: used for manipulating the faults, events, compensation and correlation sets. Scope Activity used for simplifies BPEL process flow
BPEL Empty Activity:  does not do anything but syntax is required for feature of BPEL Process but which is not perform any activity
BPEL Switch Activity:
BPEL While Activity:

 

Folks, it’s your turn to comment & suggest for improvement

Note: We have taken inputs from various folks and other weblog for making this comprehensive set of Oracle SOA-OSB interview & answers

 

Read Also:

 

Happy Coding !!
Happy Learning !!

Oracle OSB-SOA-BPEL Interview Question and Answer - Part 17
Oracle OSB-SOA-BPEL Interview Question and Answer - Part 15