Hi,
I want to give select persmissons to perticular user or anyone can select only except one main user.

What are the steps?

Regards
Pawan

to grant select privileges on a table to a single user, you will use:
GRANT SELECT ON TABLE table_name TO USER user_name

to grant this permission to everyone but a single user, you must create a group in which you will include everyone (except that user) and you will use:
GRANT SELECT ON TABLE table_name TO GROUP group_name

GRANT SELECT ON TABLE tablename1, tablename2, viewname3, ... TO user-id ;
GRANT SELECT ON TABLE tablename1, tablename2, viewname3, ... TO PUBLIC ;
GRANT ALL ON TABLE tablename, ... TO main-user ;
(Or make sure that main-user is the table owner, who always has ALL privileges.)

thanks....

If i create a new user C on linux server...
and on this server there are running two instances A and B with users A and B respectively....I want to access databases of A and B by user C and want to give select privilages to C user for databases running under A and B.

how can we do this?

On each database:
GRANT CONNECT ON DATABASE TO USER C

and then use the grants above

I logged in by User A and gave grant permissiong to user B..
su - A
first asking for database connection...
db2 connect to A
then i did
db2 GRANT CONNECT ON DATABASE TO USER B
DB20000I The SQL command completed successfully.

now login by User B
su - B
and try to connect database A but througing below
db2 connect to A user A using **
SQL1013N The database alias name or database name "A" could not be found.
SQLSTATE=42705


what I need to do?

CATALOG DATABASE A ...

by cataloging my requirement is not being full...

In this specific scenario you have to follow the following steps

first do
su - A
first asking for database connection...
db2 connect to A
then i did
db2 GRANT CONNECT ON DATABASE TO USER B
DB20000I The SQL command completed successfully.

then get details of instance for database A

then do
su - B

now you'll have to catalog the instance A using the following command
db2 catalog tcpip node <<nodename>> remote <<db2server ip>> server <<pot of node>>

now do 'db2 list node directory' and check whether the node has been cataloged

now you'll have to catalog the database

db2 catalog db <<dbname>> as alias <<alias-name>> at node <<nodename>>

where nodename is the same as the node that is specified while cataloging the node
[ points to note - database alias name cannot be same as an existing alias name or a db name ]

now do 'db2 list db directory' and check whether the database A details is displayed

now do
connect to A user <<username>> using <<password>>
[ in this case use the alias name that you have specified for database A ]

thanks to all