ORA-01653: unable to extend table string.string by string in tablespace string

ORA-01653: unable to extend table string.string by string in tablespace string

Cause: Failed to allocate an extent of the required number of blocks for a table segment in the tablespace indicated.

Action: Use ALTER TABLESPACE ADD DATAFILE statement to add one or more files to the tablespace indicated.

Alert.log:
ORA-1653: unable to extend table SYS.AUD$ by 128 in                 tablespace SYSTEM

Solution:
ALTER DATABASE DATAFILE '/oracle/DBPRD/system01.dbf' RESIZE 1000M

More Oracle DBA tips, please visit Oracle DBA Tips 

How to find the character set the database is using

To find the character set the Oracle database is using, the query is:

select * from nls_database_parameters where parameter='NLS_CHARACTERSET';

PARAMETER                 VALUE
--------------------------------------------

NLS_CHARACTERSET         AL32UTF8
NLS_NCHAR_CHARACTERSET          AL16UTF16

More Oracle DBA tips, please visit Oracle DBA Tips