|
Visual Basic Interview Questions and Answers
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
Diff type of Datatypes?
LOB (Large Object Data type).
CLOB (Stores Character Objects).
BLOB ( Store Binary Objects such as Graphic, Video Chips
and Sound files).
BFILE(Store file pointers to LOB It may Contain filename
for photo’s store on CD_ROM).
What is Tabstrip control?
Libraries of procedure external to the application but
can be called from the application.
What is Static Variable?
Its Scope will be available through out the life time.
What is DBSqlPassThrough?
It will By Passing the Jet Query Processor.
What is the starting Index value? How to locate it?
It is tab control to place our controls with in the form
in multiple sheets.
Index starts with 1.
And to identify If Tabstrip1.SelectedItem.
Index = 1 Then ..
End if
What is Parser Bug?
It is difficult to use database objects declared in a
module from within a form.
What is keyword used to compare to objects?
ISOperator Returns Boolean.
Suppose from form1 to form2 object property settings
will arise to ?
Invalid procedure call or argument (Run time error 5)
What is the return type of Instr and Strcmp?
Instr integer (Numeric position)
Strcmp - integer ( if both the string are equal they
result = 0)
Strcmp (Str1, Str2, Comparetype)
Comparing mode = 0 Binary Comparing
1 Textual Comparing
What is Implicit?
Instance of specific copy of a class with its own
settings for the properties defined in that class.
Note: The implicitly defined variable is never equal to
nothing.
Page Numbers
:
1
2
3
4
5
6
7
8
Have a Question ?
post your questions here. It
will be answered as soon as possible.
Check
Microsoft .Net Interview
Questions for more Microsoft .Net Interview Questions with answers
Check
Asp .Net Interview
Questions for more Asp .Net Interview Questions with answers
Check
.Net Database Interview
Questions for more .Net Database Interview Questions with answers
Check
.Net
Deployment Interview
Questions for more .Net Deployment Interview Questions with answers
|
