8. When constructing an XML DTD, how do you create an external entity reference in an attribute value?
Every interview session should have at least one trick question. Although possible when using SGML, XML DTDs don't support defining external entity references in attribute values. It's more important for the candidate to respond to this question in a logical way than the candidate know the somewhat obscure answer.
9. How would you build a search engine for large volumes of XML data?
The way candidates answer this question may provide insight into their view of XML data. For those who view XML primarily as a way to denote structure for text files, a common answer is to build a full-text search and handle the data similarly to the way Internet portals handle HTML pages. Others consider XML as a standard way of transferring structured data between disparate systems. These candidates often describe some scheme of importing XML into a relational or object database and relying on the database's engine for searching. Lastly, candidates that have worked with vendors specializing in this area often say that the best way the handle this situation is to use a third party software package optimized for XML data
10. What is a schema? What are the limitations of a DTD?
SCHEMA is nothing but METADATA. The schema holds all the information of the xml file that is to be deployed in the project. Metadata is nothing about data about data since we know that xml is used for data representation language we will be able to understand what metadata is. Metadata includes the tags that are going to be exchanged to and fro from another xml file. DTD (DATA TYPE DEFINITION) which supervises two conditions namely well formed ness and closeness of the xml file. So the user should be aware of what tags he was put into use of this xml file 'A' should be intimated to another application's XML file 'B', by then our xml file will interact with the another xml file, this is the major limitation and mandatory issue that the developers should follow.
11. What are the differences between SAX and DOM parsers?
Both SAX and DOM are used to parse the XML document. Both have advantages and disadvantages and can be used in our programming depending on the situation
SAX:
1. Parses node by node
2. Doesn’t store the XML in memory
3. We can’t insert or delete a node
4. Top to bottom traversing
DOM:
1. Stores the entire XML document into memory before processing
2. Occupies more memory
3. We can insert or delete nodes
4. Traverse in any direction.
If we need to find a node and doesn’t need to insert or delete we can go with SAX itself otherwise DOM provided we have more memory.
12. What parser would you use for searching a huge XML?
SAX, event based XML parser is probably what is needed to search huge file. DOM store the whole content on memory which is in huge file is not good since it uses a lot of memory. SAX is event based that handle XML elements when it find it.
13. When a XML file has a DTD declared which is not accessible to the parser, what would happen?
Everything should be fine. DTD is used for validation, parsing doesn't require DTD or schema.
14. How do you say XML is secured language on the information exchange over the network?
Actually it isn’t. XML may be easy to write and even parse, but the use of XML as a medium of B2B data interchange is still bleak. XML is used mainly for Application integration as it is just within the organization and where major security issues will not rise. Also, with the ESB revolution and the whole industry striding towards SOA, XML is able to make its own impact. But still, for B2B integrations, organizations prefer to use EDI (electronic Data Interchange) as compared to XML because EDI has withstood the test of time on security and also have tailor made templates for each industry. XML is still in the immature stage; its still evolving. It will take a long time before we get to see XML taking up the place of EDI.
15. What is the main difference between XML and HTML?
HTML is basically for the presentation of the data
It Uses predefined tags for the presentation of the data.
XML is for describing the data
User defined tags are used to describe the data structure and data.
Every interview session should have at least one trick question. Although possible when using SGML, XML DTDs don't support defining external entity references in attribute values. It's more important for the candidate to respond to this question in a logical way than the candidate know the somewhat obscure answer.
9. How would you build a search engine for large volumes of XML data?
The way candidates answer this question may provide insight into their view of XML data. For those who view XML primarily as a way to denote structure for text files, a common answer is to build a full-text search and handle the data similarly to the way Internet portals handle HTML pages. Others consider XML as a standard way of transferring structured data between disparate systems. These candidates often describe some scheme of importing XML into a relational or object database and relying on the database's engine for searching. Lastly, candidates that have worked with vendors specializing in this area often say that the best way the handle this situation is to use a third party software package optimized for XML data
10. What is a schema? What are the limitations of a DTD?
SCHEMA is nothing but METADATA. The schema holds all the information of the xml file that is to be deployed in the project. Metadata is nothing about data about data since we know that xml is used for data representation language we will be able to understand what metadata is. Metadata includes the tags that are going to be exchanged to and fro from another xml file. DTD (DATA TYPE DEFINITION) which supervises two conditions namely well formed ness and closeness of the xml file. So the user should be aware of what tags he was put into use of this xml file 'A' should be intimated to another application's XML file 'B', by then our xml file will interact with the another xml file, this is the major limitation and mandatory issue that the developers should follow.
11. What are the differences between SAX and DOM parsers?
Both SAX and DOM are used to parse the XML document. Both have advantages and disadvantages and can be used in our programming depending on the situation
SAX:
1. Parses node by node
2. Doesn’t store the XML in memory
3. We can’t insert or delete a node
4. Top to bottom traversing
DOM:
1. Stores the entire XML document into memory before processing
2. Occupies more memory
3. We can insert or delete nodes
4. Traverse in any direction.
If we need to find a node and doesn’t need to insert or delete we can go with SAX itself otherwise DOM provided we have more memory.
12. What parser would you use for searching a huge XML?
SAX, event based XML parser is probably what is needed to search huge file. DOM store the whole content on memory which is in huge file is not good since it uses a lot of memory. SAX is event based that handle XML elements when it find it.
13. When a XML file has a DTD declared which is not accessible to the parser, what would happen?
Everything should be fine. DTD is used for validation, parsing doesn't require DTD or schema.
14. How do you say XML is secured language on the information exchange over the network?
Actually it isn’t. XML may be easy to write and even parse, but the use of XML as a medium of B2B data interchange is still bleak. XML is used mainly for Application integration as it is just within the organization and where major security issues will not rise. Also, with the ESB revolution and the whole industry striding towards SOA, XML is able to make its own impact. But still, for B2B integrations, organizations prefer to use EDI (electronic Data Interchange) as compared to XML because EDI has withstood the test of time on security and also have tailor made templates for each industry. XML is still in the immature stage; its still evolving. It will take a long time before we get to see XML taking up the place of EDI.
15. What is the main difference between XML and HTML?
HTML is basically for the presentation of the data
It Uses predefined tags for the presentation of the data.
XML is for describing the data
User defined tags are used to describe the data structure and data.
