|
1.What is normalization? - Well a
relational database is basically
composed of tables that contain related
data. So the Process of organizing this
data into tables is actually referred to
as normalization.
2.What is a Stored Procedure? - Its
nothing but a set of T-SQL statements
combined to perform a single task of
several tasks. Its basically like a
Macro so when you invoke the Stored
procedure, you actually run a set of
statements.
3.Can you give an example of Stored
Procedure? - sp_helpdb , sp_who2,
sp_renamedb are a set of system defined
stored procedures. We can also have user
defined stored procedures which can be
called in similar way.
4.What is a trigger? - Triggers are
basically used to implement business
rules. Triggers is also similar to
stored procedures. The difference is
that it can be activated when data is
added or edited or deleted from a table
in a database.
5.What is a view? - If we have several
tables in a db and we want to view only
specific columns from specific tables we
can go for views. It would also suffice
the needs of security some times
allowing specfic users to see only
specific columns based on the permission
that we can configure on the view. Views
also reduce the effort that is required
for writing queries to access specific
columns every time.
6.What is an Index? - When queries are
run against a db, an index on that db
basically helps in the way the data is
sorted to process the query for faster
and data retrievals are much faster when
we have an index.
7.What are the types of indexes
available with SQL Server? - There are
basically two types of indexes that we
use with the SQL Server. Clustered and
the Non-Clustered.
8.What is the basic difference between
clustered and a non-clustered index? -
The difference is that, Clustered index
is unique for any given table and we can
have only one clustered index on a
table. The leaf level of a clustered
index is the actual data and the data is
resorted in case of clustered index.
Whereas in case of non-clustered index
the leaf level is actually a pointer to
the data in rows so we can have as many
non-clustered indexes as we can on the
db.
9.What are cursors? - Well cursors help
us to do an operation on a set of data
that we retreive by commands such as
Select columns from table. For example :
If we have duplicate records in a table
we can remove it by declaring a cursor
which would check the records during
retreival one by one and remove rows
which have duplicate values.
10.When do we use the UPDATE_STATISTICS
command? - This command is basically
used when we do a large processing of
data. If we do a large amount of
deletions any modification or Bulk Copy
into the tables, we need to basically
update the indexes to take these changes
into account. UPDATE_STATISTICS updates
the indexes on these tables accordingly.
11.Which TCP/IP port does SQL Server run
on? - SQL Server runs on port 1433 but
we can also change it for better
security.
From where can you change the default
port? - From the Network Utility TCP/IP
properties –> Port number.both on client
and the server.
12.Can you tell me the difference
between DELETE & TRUNCATE commands? -
Delete command removes the rows from a
table based on the condition that we
provide with a WHERE clause. Truncate
will actually remove all the rows from a
table and there will be no data in the
table after we run the truncate command.
13.Can we use Truncate command on a
table which is referenced by FOREIGN
KEY? - No. We cannot use Truncate
command on a table with Foreign Key
because of referential integrity.
14.What is the use of DBCC commands? -
DBCC stands for database consistency
checker. We use these commands to check
the consistency of the databases, i.e.,
maintenance, validation task and status
checks.
15.Can you give me some DBCC command
options?(Database consistency check) -
DBCC CHECKDB - Ensures that tables in
the db and the indexes are correctly
linked.and DBCC CHECKALLOC - To check
that all pages in a db are correctly
allocated. DBCC SQLPERF - It gives
report on current usage of transaction
log in percentage. DBCC CHECKFILEGROUP -
Checks all tables file group for any
damage.
16.What command do we use to rename a
db? - sp_renamedb ‘oldname’ , ‘newname’
Well sometimes sp_reanmedb may not work
you know because if some one is using
the db it will not accept this command
so what do you think you can do in such
cases? - In such cases we can first
bring to db to single user using
sp_dboptions and then we can rename that
db and then we can rerun the
sp_dboptions command to remove the
single user mode.
17.What is the difference between a
HAVING CLAUSE and a WHERE CLAUSE? -
Having Clause is basically used only
with the GROUP BY function in a query.
WHERE Clause is applied to each row
before they are part of the GROUP BY
function in a query.
18.What do you mean by COLLATION? -
Collation is basically the sort order.
There are three types of sort order
Dictionary case sensitive, Dictonary -
case insensitive and Binary.
19.What is a Join in SQL Server? - Join
actually puts data from two or more
tables into a single result set.
20.Can you explain the types of Joins
that we can have with Sql Server? -
There are three types of joins: Inner
Join, Outer Join, Cross Join
21.When do you use SQL Profiler? - SQL
Profiler utility allows us to basically
track connections to the SQL Server and
also determine activities such as which
SQL Scripts are running, failed jobs
etc..
22.What is a Linked Server? - Linked
Servers is a concept in SQL Server by
which we can add other SQL Server to a
Group and query both the SQL Server dbs
using T-SQL Statements.
23.Can you link only other SQL Servers
or any database servers such as Oracle?
- We can link any server provided we
have the OLE-DB provider from Microsoft
to allow a link. For Oracle we have a
OLE-DB provider for oracle that
microsoft provides to add it as a linked
server to the sql server group.
24.Which stored procedure will you be
running to add a linked server? -
sp_addlinkedserver, sp_addlinkedsrvlogin
25.What are the OS services that the SQL
Server installation adds? - MS SQL
SERVER SERVICE, SQL AGENT SERVICE, DTC
(Distribution transac co-ordinator)
26.Can you explain the role of each
service? - SQL SERVER - is for running
the databases SQL AGENT - is for
automation such as Jobs, DB Maintanance,
Backups DTC - Is for linking and
connecting to other SQL Servers
27.How do you troubleshoot SQL Server if
its running very slow? - First check the
processor and memory usage to see that
processor is not above 80% utilization
and memory not above 40-45% utilization
then check the disk utilization using
Performance Monitor, Secondly, use SQL
Profiler to check for the users and
current SQL activities and jobs running
which might be a problem. Third would be
to run UPDATE_STATISTICS command to
update the indexes
28.Lets say due to N/W or Security
issues client is not able to connect to
server or vice versa. How do you
troubleshoot? - First I will look to
ensure that port settings are proper on
server and client Network utility for
connections. ODBC is properly configured
at client end for connection ——Makepipe
& readpipe are utilities to check for
connection. Makepipe is run on Server
and readpipe on client to check for any
connection issues.
29.What are the authentication modes in
SQL Server? - Windows mode and mixed
mode (SQL & Windows).
30.Where do you think the users names
and passwords will be stored in sql
server? - They get stored in master db
in the sysxlogins table.
31.What is log shipping? Can we do
logshipping with SQL Server 7.0 -
Logshipping is a new feature of SQL
Server 2000. We should have two SQL
Server - Enterprise Editions. From
Enterprise Manager we can configure the
logshipping. In logshipping the
transactional log file from one server
is automatically updated into the backup
database on the other server. If one
server fails, the other server will have
the same db and we can use this as the
DR (disaster recovery) plan.
32.Let us say the SQL Server crashed and
you are rebuilding the databases
including the master database what
procedure to you follow? - For restoring
the master db we have to stop the SQL
Server first and then from command line
we can type SQLSERVER –m which will
basically bring it into the maintenance
mode after which we can restore the
master db.
33.Let us say master db itself has no
backup. Now you have to rebuild the db
so what kind of action do you take? - (I
am not sure- but I think we have a
command to do it).
34.What is BCP? When do we use it? -
BulkCopy is a tool used to copy huge
amount of data from tables and views.
But it won’t copy the structures of the
same.
35.What should we do to copy the tables,
schema and views from one SQL Server to
another? - We have to write some DTS
packages for it.
What are the different types of joins
and what dies each do?
36.What are the four main query
statements?
37.What is a sub-query? When would you
use one?
38.What is a NOLOCK?
39.What are three SQL keywords used to
change or set someone’s permissions?
40.What is the difference between HAVING
clause and the WHERE clause?
41.What is referential integrity? What
are the advantages of it?
42.What is database normalization?
43.Which command using Query Analyzer
will give you the version of SQL server
and operating system?
44.Using query analyzer, name 3 ways you
can get an accurate count of the number
of records in a table?
45.What is the purpose of using COLLATE
in a query?
46.What is a trigger?
47.What is one of the first things you
would do to increase performance of a
query? For example, a boss tells you
that “a query that ran yesterday took 30
seconds, but today it takes 6 minutes”
48.What is an execution plan? When would
you use it? How would you view the
execution plan?
49.What is the STUFF function and how
does it differ from the REPLACE
function?
50.What does it mean to have
quoted_identifier on? What are the
implications of having it off?
51.What are the different types of
replication? How are they used?
52.What is the difference between a
local and a global variable?
53.What is the difference between a
Local temporary table and a Global
temporary table? How is each one used?
54.What are cursors? Name four types of
cursors and when each one would be
applied?
55.What is the purpose of UPDATE
STATISTICS?
56.How do you use DBCC statements to
monitor various aspects of a 57.SQL
server installation?
58.How do you load large data to the SQL
server database?
59.How do you check the performance of a
query and how do you optimize it?
60.How do SQL server 2000 and XML
linked? Can XML be used to access data?
61.What is SQL server agent?
62.What is referential integrity and how
is it achieved?
63.What is indexing?
64.What is normalization and what are
the different forms of normalizations?
65.Difference between server.transfer
and server.execute method?
66.What id de-normalization and when do
you do it?
67.What is better - 2nd Normal form or
3rd normal form? Why?
68.Can we rewrite subqueries into simple
select statements or with joins?
Example?
69.What is a function? Give some
example?
70.What is a stored procedure?
71.Difference between Function and
Procedure-in general?
72.Difference between Function and
Stored Procedure?
73.Can a stored procedure call another
stored procedure. If yes what level and
can it be controlled?
74.Can a stored procedure call
itself(recursive). If yes what level and
can it be controlled.?
75.How do you find the number of rows in
a table?
76.Difference between Cluster and
Non-cluster index?
77.What is a table called, if it does
not have neither Cluster nor Non-cluster
Index?
78.Explain DBMS, RDBMS?
79.Explain basic SQL queries with SELECT
from where Order By, Group By-Having?
80.Explain the basic concepts of SQL
server architecture?
81.Explain couple pf features of SQL
server
Scalability, Availability, Integration
with internet, etc.)?
82.Explain fundamentals of Data ware
housing & OLAP?
Explain the new features of SQL server
2000?
83.How do we upgrade from SQL Server 6.5
to 7.0 and 7.0 to 2000?
84.What is data integrity? Explain
constraints?
85.Explain some DBCC commands?
86.Explain sp_configure commands, set
commands?
87.Explain what are db_options used for?
88.What is the basic functions for
master, msdb, tempdb databases?
89.What is a job?
90.What are tasks?
91.What are primary keys and foreign
keys?
92.How would you Update the rows which
are divisible by 10, given a set of
numbers in column?
93.If a stored procedure is taking a
table data type, how it looks?
94.How m-m relationships are
implemented?
95.How do you know which index a table
is using?
96.How will oyu test the stored
procedure taking two parameters namely
first name and last name returning full
name?
97.How do you find the error, how can
you know the number of rows effected by
last SQL statement?
98.How can you get @@error and @@rowcount
at the same time?
99.What are sub-queries? Give example?
In which case sub-queries are not
feasible?
100.What are the type of joins? When do
we use Outer and Self joins?
101.Which virtual table does a trigger
use?
102.How do you measure the performance
of a stored procedure?
103.Questions regarding Raiseerror?
104.Questions on identity?
105.If there is failure during updation
of certain rows, what will be the state? |