BizTalk Interview Questions - Schemas - Part 1

I hope these series of blogs helps you in preparing for the Biz Talk expertise for clearing the interview and become the BizTalk Developer.

I have referenced many sites and blogs for these questionnaires, so please don't forget to give credit for the actual owner.
Question have been referred from the below website
https://social.technet.microsoft.com/wiki/contents/articles/19063.biztalk-developer-interview-questions-and-answers-schema.aspx 

1.      What are Schemas and different type of Schema’s

A schema is a term borrowed from the database world to describe the structure of data in relational tables. In the context of XML, a schema describes a model for a whole class of documents. See MSDN:  Different Types of BizTalk Schemas. 

1) Document Schema:-Regular schema to define the structure of an XML instance message 

2) Flat file schema: - A flat file schema defines the structure of a class of instance messages that use a flat file format, either delimited or positional or some combination. 

3) Envelope Schema: - An envelope schema is a special type of XML schema. Envelope schemas are used to define the structure of XML envelopes, which are used to wrap one or more XML business documents into a single XML instance message 

4) Property Schema:- A property schema is a simple version of a BizTalk schema that plays a role in the process of copying promoted properties back and forth between the instance message and the message context. Property promotion is the process of copying specific values from deep within an instance message to the message context which can be accessed by various BizTalk Server components to perform actions such as message routing. Promoted property values can also be copied in the other direction, from the more easily accessible message context back into the depths of the instance message, just before the instance message is sent to its destination. For more info visit: Different-types-of-BizTalk-Schemas

2.      What is the difference between a Document Schema and a Property Schema?

A document schema is like any regular schema, whereas a Property schema consists of only child elements under a root node.

3.      Can an Envelope schema consist of more than one schema type?

Yes. Technically it is possible. For more Info on envelop schema please visit Envelop Schemas

4.      Can a flat file message be processing without a pipeline?

No. A Pipeline's job is to convert any external format into XML, be it a flat file or EDI or anything else.

5.      Can multiple messages be processed or batched without an envelope schema?

It is possible to process multiple messages, without an envelope

  

6.      What is property promotion, why is it required?

When a property is promoted, it is exposed to the orchestration/send port filters etc. Property promotion is the process of copying specific values from deep within an instance message to the message context which can be accessed by various BizTalk Server components to perform actions such as message routing. Promoted property values can also be copied in the other direction, from the more easily accessible message context back into the depths of the instance message, just before the instance message is sent to its destination.

  

7.      What are un-typed messages, how does one create them?

A message created in BizTalk Orchestration is bound to a schema, this is a typed message. In un-typed messages, the message is bound to System.Xml.XmlDocument instead of a schema.

8.      What is the target namespace for schema?

Target Namespace is to schema what a namespace is to .Net Object and root node as a class name.

9.      Is it possible to create a custom data type and use it in a schema?
Yes, it's possible to create custom data types and it can be used across the schema. See  custom-data-type

10.  Can schema have two nodes with the same name and different datatypes?
Yes, as long as they are not in the same scope. 

11.  Can schema have multiple root nodes?
Yes, a schema (XSD) can have multiple root nodes. In case you have a schema with multiple root nodes you will end up with multiple message types declared in BizTalk, one for every root node. So when you want to create a message you will need to specify exactly which message type you are going to use! 

12.  Is it possible to include and import in a single schema?
Yes, it is possible, both are the ways to utilize already existing schema. The only condition is the schema which is included should have same TargetNamespace or no namespace.

13.  By default, what is the data type of elements in a schema?
xs:string 

14.  What is the difference between Group Max occurs, Group Min Occurs and Max occurs, Min Occurs?
These are all node properties. See MSDN Node Properties
Group Max Occurs: Specifies the maximum number of times that to the underlying group content of the selected All Group node can occur.
Group Min Occurs: Specifies the minimum number of times that the underlying group content of the selected All Group node can occur.
Max Occurs: Specifies the maximum number of times that the element corresponding to the selected Record node can occur.
Min Occurs:  Specifies the minimum number of times that the element corresponding to the selected Record node can occur.

15.  What is BlockDefault property used for?
Use the BlockDefault property to prevent or restrict the types of derivations that can be used in instance messages for all data types defined by the schema being edited. See MSDN BlockDefault (Node Property of All Schemas)

16.  What is a canonical schema?
A canonical schema is a design pattern, which is applied within a service oriented paradigm, and within BizTalk server context establish the loose coupling between systems. Through performing the transformation of messages from one system to canonical schema and from the canonical schema to message of another system, systems have no direct relation with each other. The canonical schema can also be viewed as an internal schema in BizTalk and aid you in structuring your solution through best practice of creating separate projects for maps, orchestrations, internal and external schemas. Another advantage of using a canonical schema is that it reduces the number of transformations you need. If you need a to map a few types of inbound message coming from different parties to a few outbound messages, you can create a map to your canonical schema for each inbound schema and then a map from your canonical schema to each outbound schema. If for example you have three types of incoming that needs to be mapped to three types of outgoing messages you will only need to build and maintain six maps instead of nine. 

17.  What is the correlation property schema?
Correlation types define a set of properties on which you will be correlating messages. These can be any properties which were previously defined in a property schema (see question 2) and deployed with some BizTalk Project including "system" properties deployed with the GlobalPropertySchemas which is installed as part of the base BizTalk install. A correlation set defines a set of properties and values for these properties that a message must contain to be processed by a particular orchestration. See MSDN Correlation Sets. 

18.  Difference between Flat File Schema and XML schema?
A flat file schema defines the structure of a class of instance messages that use a flat file format, either delimited or positional or some combination thereof. Because the native semantic capabilities of XSD do not accommodate all of the requirements for defining the structure of flat file instance messages—such as the various types of delimiters that might be used for different records and fields within the flat file—BizTalk Server uses the annotation capabilities of XSD to store this extra information within an XSD schema. BizTalk Server defines a rich set of specific annotation tags that can be used to store all of the required additional information. See MSDN Different Types of BizTalk Schemas.
An XML Schema is basically a contract of your message and defines it. The XML Schema definition (XSD) language defines the structure of an XML instance message, and this is the intended purpose of XSD, such schemas use XSD in a straightforward way. See MSDN Different Types of BizTalk Schemas.

19.  Can we have schema without a target namespace? What will be its Message Type?
Yes, we can have a schema without target namespace and its message type will be the Root node.

20.  Which property is only available for the flat file schema?
Custom Date/time property is only available for flat file schema.

to be continued in the next post, and also please visit for more BizTalk related content.