Wednesday, April 25, 2012

Learn SOA using Q&A

Q)    What is SOA?
R)    As Per Gartner, "Service Oriented Architecture (SOA) is a client-server software design approach in which an application consists of software services and software service consumers (also known as clients or service requesters). SOA differs from the more general client/server model in its definitive emphasis in loose coupling between software components, and in its use of separately standing interfaces."

Q) When should you use SOA?
R) SOA should be the proposed when
1) There are multiple applications which are running in an enterprise and if there is a data dependency in the applications (i.e. data output from one application is data input for another application).
2) And This interfacing is not automated (i.e. it is being done manually or some other tedious method which leads to data issues)
3) And The enterprise is huge and can afford costs for implementing SOA. (SOA software and corresponding hardware would be costly, which makes it suited for big companies)
4) And Speed of implementing the integration is important. (Instead of SOA, custom interfaces can be written to integrate all the applications of the process, but that would be a time consuming process, which will create custom interfaces, requiring lot of testing, maintenance and support. By the time you build it the need for integration might not be there.) SOA will not only help you to build your applications faster. The maintenance and support costs would be minimal as you would be using standard adapters/operations provided by your SOA software.  

Q) When should you propose Oracle SOA?
A) It would be a easy sell for Oracle’s SOA stack when customer is using lot of other Oracle products. If they are not using many Oracle products, then you might have to think about alternative SOA products from IBM, Tibco etc.

Q) When does the SOA process start or get triggered?
A) It would start when the first application in the new business process (which needs to be implemented using SOA) gets the data required for the process to start. It might then provide the data to SOA process in variety of different ways such as SOAP post or place the data in a file at particular location which the SOA process is polling etc. SOA process as such would never have it own UI in the process.

Fresher interview questions for Oracle Database, SQL, Forms & Reports

Interviewing a fresher for working on Oracle projects. Following points can be handy in checking their knowledge in different areas of RDBMS concepts, SQL, PL/SQL, Forms and Reports.

Introduction to DBMS
Database concepts
E-R Diagrams
Types of Databases
Database Model
Oracle SQL
Basics of Oracle SQL
Character, Number and Miscellaneous Functions
Date and Conversion Functions
Aggregate Functions, GROUP BY and HAVING clauses
Equijoins, Outer Joins
SET Operators
Complex Joins
Views, Indexes and Sequences
Data Dictionary and Security
Regular expressions and hierarchical queries
Oracle PL/SQL
PL/SQL Programming Fundamentals
Conditional Statements: IF & CASE
Iterative Loops
Error handling and exceptions in PL/SQL
Basics of PL/SQL Cursors
Advanced Cursors
Compound Triggers
Native Dynamic SQL
Bulk SQL
Introduction to SQL * Loader
Oracle Forms
Introduction to Forms GUI
Forms Layout editor and property palette
Manipulating properties and property classes
Executing PL/SQL block(s) and Items in Forms
Defining Master-Detail relationships in Forms
Using Triggers in Forms
Alerts and Editors
LOV and Record groups in Forms
Passing parameters to a form and canvas views
Editing/Creating Form Menus
Error Handling in Forms
Oracle Reports
Data Modeling in Reports
Introduction to Reports GUI
Reports Layout editor
Implementing formulas and summaries in report
Embedded SQL in Reports
Embedded PL/SQL blocks in Reports