Overview

This document explains the initialization parameters and file path parameters that are automatically set after installing Tibero.

Method

DB Initialization Parameters (default parameter)

DB_NAME

Sets the database name. (Default: tibero)

ALISTENER_PORT

Sets the port number used by the listener. (Default: 8629)

Along with SHMKEY, when running two or more database instances on one server, you must set this differently for each.

CONTROL_FILES

Specifies the location where the control files exist, set as an absolute path.

MAX_SESSION_COUNT

Sets the maximum number of sessions users can connect to and use simultaneously.
 

TOTAL_SHM_SIZE

Sets the total shared memory size to be used inside the database instance.

The total shared memory size should be set to exceed the calculated value of DB_CACHE_SIZE + LOG_BUFFER + 20M (allocated at initial startup)
+ (WTHR_PROC_CNT * WTHR_PER_PROC) * 1M.
 

MEMORY_TARGET

Sets the total memory size to be used inside the database instance.

This is the total of all shared memory and all memory used by each process, set as the calculated value of TOTAL_SHM_SIZE + (total memory used by processes).

DB File Path Parameter

DB_CREATE_FILE_DEST

This parameter sets the location where the database's data files are stored.
If a path is not explicitly specified when creating a data file, the file is created in the path set by this parameter by default.
 

Note
Since directories are managed according to the nature of the tasks performed, explicitly declare the appropriate directory for the intended use when creating data files. 

The following is an example of checking the data file.

-- tbsql login
# tbsql sys/tibero

-- Check DB file creation path
SQL> show param DB_CREATE_FILE_DEST
NAME TYPE VALUE
---------------------------- -------- ----------------------------------------
DB_CREATE_FILE_DEST DIRNAME /tbdata/dbfile/

-- Check file creation when path is not set
SQL> create tablespace test_ts datafile 'test_ts.dtf' size 1m extent management local
segment space management auto;
Tablespace 'TEST_TS' created.
SQL> !ls -al /tbdata/dbfile/test_ts.dtf
-rw-------. 1 tibero dba 1048576 Nov 15 11:00 /tbdata/dbfile/test_ts.dtf

-- Check file creation when path is set
SQL> create tablespace test_ts2 datafile '/tbdata/dbfile/test_ts2.dtf' size 1m extent
management local segment space management auto;
Tablespace 'TEST_TS2' created.
SQL> !ls -al /tbdata/dbfile/test_ts2.dtf
-rw-------. 1 tibero dba 1048576 Nov 15 11:02 /tbdata/dbfile/test_ts2.dtf

LOG_ARCHIVE_DEST

This parameter sets the location where archive log files for recovery are created when operating the database in Archive mode.
Archive log files are essential for recovery, and if the archive directory becomes 100% full during operation, the database operation will stop, so you must establish a regular backup policy.

The details of the LOG_ARCHIVE_DEST parameter are as follows.

FLASHBACK

DB_RECYCLE_CACHE_SIZE

This parameter specifies the size of the RECYCLE Buffer Pool.
The details of the DB_RECYCLE_CACHE_SIZE parameter are as follows.

USE_RECYCLEBIN

This parameter provides a recovery function for objects dropped by user mistake.
When a table is dropped, the object is moved to the recycle bin and renamed before it is actually dropped.
To permanently delete this dropped table, you need to perform a Purge operation.

The details of the USE_RECYCLEBIN parameter are as follows.

The following is an example of recovering a dropped table.

-- Connect to tbsql
# tbsql tibero/tmax

-- Enable recycle bin feature
SQL> alter session set USE_RECYCLEBIN=Y;
Session altered.

-- Create test table
SQL> create table test_recyclebin ( c1 number ) ;
Table 'TEST_RECYCLEBIN' created.

-- Insert into test table
SQL> declare
begin
for i in 1..10000 loop
insert into TEST_RECYCLEBIN values (i);
end loop;
end;
/
PSM completed.
SQL> commit;
Commit completed.
SQL> select count(*) from TEST_RECYCLEBIN;
COUNT(*)
----------
10000

-- Delete test table
SQL> drop table TEST_RECYCLEBIN;
Table 'TEST_RECYCLEBIN' dropped.

-- Query table
SQL> select * from TEST_RECYCLEBIN;
TBR-8033: Specified schema object was not found.
-- Check RECYCLE BIN
OBJECT_NAME ORIGINAL_NAME TYPE TS_NAME CREATETIME DROPTIME
DROPTSNBASE_OBJECTSPACE
---------------- --------------- ------ ------- ------------------- ------------------- -
-----------------------
_TIBERO_TBL329600 TEST_RECYCLEBIN TABLE USR 2023-11-15:11:18:03 2023-11-15:13:08:06
336071

-- Recover
SQL> flashback table TEST_RECYCLEBIN to before drop;
Flashbacked.
SQL> select count(*) from TEST_RECYCLEBIN;
COUNT(*)
----------
10000