DDL commands are auto commited commands, after DDL job execution
no need to commit again
An index is a method of allowing faster retrieval of records.
A view is an virtual table formed using a single table or one or more tables.
A synonym is an alternative name for objects such as tables, views, sequences, stored procedures, and other database objects
It consists of,
one or more data files.
one or more control files.
two or more redo log files.
The Database contains
one or more rollback segments
one or more tablespaces
Data dictionary tables
User objects (table,indexes,views etc.,)
The server that access the database consists of,
SGA (Database buffer, Dictionary Cache Buffers, Redo log buffers, Shared SQL pool)
SMON (System MONito)
PMON (Process MONitor)
LGWR (LoG Write)
DBWR (Data Base Write)
CKPT (Check Point)
User Process with associated PGS
its called snap shot too old error.
it comes if a user is updates a table with loop option, in another session an user to see the info(select) then its shows ora-1555 error.
Exceptions can be handled in various ways in the stored procedures.
Method (1) could be using EXCEPTION block in the procedure within which use WHEN <exceptionname> THEN.
Method (2) could be declare a variable in DECLARE section as EXCEPTION type, raise it wherever required using RAISE <exception variable name> and handle it in EXCEPTION part using WHEN clause.
Method (3) could be using the keywords SQLCODE & SQLERRM to display error no and error code.