What is the different between Microsoft ODBC Driver and Oracle OBDC Driver?

Visual Basic Interview Questions and Answers

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50. What is the different between Microsoft ODBC Driver and Oracle OBDC Driver?

Microsoft ODBC driver will support all the methods and properties of Visual Basic. Where as the Oracle not.

51. What the RDO Methods and Events?

Methods Events
Begin Trans Validate
Commit Trans Reposition
Rollback Trans Error
Cancel Query Complied
Refresh
Update Controls
Update row

52. What is MAPI ?

Messaging Application programming Interface.

53. What is MDI form?

MDI Styles?

54. What are the locks available in Visual Basic?

Locking is the process by which a DBMS restricts access to a row in a multi-user environment 4 types of locks. They are
1. Batch Optimistic
2. Optimistic
3. Pessimistic
4. ReadOnly
Operations in a relational database act on a complete set of rows. The set of rows returned by a SELECT statement consists of all the rows that satisfy the conditions in the WHERE clause of the statement. This complete set of rows returned by the statement is known as the result set.
Applications, especially those that are interactive and online, cannot always work effectively with the entire result set as a unit.
These applications need a mechanism to work with one row or a small block of rows at a time. Cursors are an extension to result sets that provide that mechanism.
Cursor or lock type Advantages Disadvantages AdOpenForwardOnly (Default) Low resource requirements Cannot scroll backward No data concurrency AdOpenStatic Scrollable (Wont detect changes made at the same time by another application) No data concurrency AdOpenKeyset Some data concurrency Scrollable Higher resource requirements Not available in disconnected scenario AdOpenDynamic High data concurrency Scrollable Highest resource requirements Not available in disconnected scenario AdLockReadOnly Low resource requirements Highly scalable Data not updatable through cursor AdLockBatchOptimistic Batch updates Allows disconnected scenarios Other users able to access data Data can be changed by multiple users at once AdLockPessimistic Data cannot be changed by other users while locked Prevents other users from accessing data while locked AdLockOptimistic Other users able to access data Data can be changed by multiple users at once

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Other Interview Questions

• How do you register a component?
• Name and explain the different compatibility types when creating a COM component
• Why is it important to use source control software for source code?
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• Name the four different locking type in ADO and describe them briefly.
• Describe Database Connection pooling (relative to MTS )?
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• Under the ADO Command Object, what collection is responsible for input to stored procedures?
• What are some benefits of using MTS?
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• Describe and In Process vs. Out of Process component. Which is faster?
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• Can We create CGI scripts in VB??
• Dim x, y as integer. What is x and y data type?
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• What is frx?
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• What is view Port?
• What are the different types of error?
• What is the diff between the Std and Class Module?
• What is Mixed Cursors?
• Drag and Drop state numbers and functions?
• What are the Style Properties of Combo Box?
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• What are the record set types?
• Different type of Instantiation?
• What is the different between Microsoft ODBC Driver and Oracle OBDC Driver?
• Diff type of Datatypes?
• What is keyword used to compare to objects?
• How can we call Stored procedure of Back End in RDO and ADO ?
• What is the max size allowed for Extension in Visual Basic?
• Referential Integrity (Take care By jet database Engine). Cascade Delete, Cascade Update is done setting property of Attributes.?
• What are the Technologies for Accessing Database from Visual Basic?set?
• What is Dataware Control?
• Record set types and Number available in VB?
• Visual Basic Interview Questions only