What is Lgwr in Oracle database?
The log writer process (LGWR) is responsible for redo log buffer management—writing the redo log buffer to a redo log file on disk. LGWR writes all redo entries that have been copied into the buffer since the last time it wrote.
How many Lgwr processes are there in Oracle?
one LGWR process
While there is always only one LGWR process for an Oracle instance, Oracle allows busy DML databases to spawn multiple log writer factotum processes (multiple LGWR slave processes that are owned and governed by the master LGWR).
What is Oracle_sid environment variable?
The ORACLE_SID environment variable specifies the default server instance for current connection. ORACLE_SID is used to distinguish current instance from other Oracle Database instances that you may create later and run concurrently on the same host computer. The ORACLE_SID value is case-sensitive in UNIX environments.
How do I find the global database name in Oracle 10g?
The easiest way of finding the database name is: select * from global_name; This view is granted to PUBLIC, so anybody can query it. Here first one “ORCL” is database name,may be your system “XE” and other what was given on oracle downloading time.
When a transaction is committed what does the Lgwr do?
Whenever a transaction is committed, LGWR writes the transaction redo records from the redo log buffer of the SGA to a redo log file, and assigns a system change number (SCN) to identify the redo records for each committed transaction.
When did Lgwr write to log files?
LGWR writes redo log entries into an on-line redo log file when transactions commit and the log buffer files are full.
Where Lgwr process writes information?
The Log Writer process is responsible for writing the contents of the redo log buffer to the log file on disk, and for management of the log buffer. Redo log data is always written first to a buffer in memory, then written to disk by the LGWR process when: LGWR is not active for three seconds.
What is the difference between Pmon and Smon?
PMON and SMON are two required background processes. PMON is the Process Monitor which is responsible for recovering processes when the user process fails. PMON does the process cleanup. SMON is the System Monitor which is responsible for recovering the system after a failure.
Where is Oracle_sid stored?
registry
ORACLE_SID is stored in the registry. Note that there are no spaces around the equal sign. In Windows, the LOCAL command can also be used to define the ORACLE_SID.
What is Oracle Global name?
From Oracle FAQ. A global name refers to the full name of a database (including its domain) which uniquely identifies it from any other database. An example global name might be FaqDB1.orafaq.com. If you set the GLOBAL_NAMES parameter to TRUE, all database link names must be valid global names.
How do I find my global database name?
You can find out what the global name is for your database by executing the following query from SQL*Plus: select * from global_name; It is also possible to alter the global name of an existing database with the following command: alter database rename global_name to
