Various RDBMS comparisons and characteristics

	Oracle	IBM DB2 LUW	MS SQL	Postgre SQL	IBM Netezza
to connect to DB	set sid,conn / as sysdba	DB2 connect to <Db name>	thru SSMS servername/instance name	pgsql,pgsql/c <Db name>	nzsql,nzsql/c <Db name>
List Db's on server	ps -ef|grep pmon	db2 list database;	select name from sys.databases;	SELECT datname FROM pg_database	select name from _v_database;
default port	1521	50000	1433	5432	5480
backup methods	cold,hot,rman,expdp/exp	offline/online,export	full,log,table level	pgdump	full,Incremental,table export
instance/DB's	one instance per DB except Rac	one instance many Db's	one instance many Db's	one instance many DB's	one instance many Db's
to start/shutdown DB	set sid,conn / as sysdba	db2start/db2stop	SSMS/offline/online	su postgres -c 'pg_ctl start -D /usr/local/pgsql/data -l serverlog'	nzstop/nzstart
	startup/shutdown
error log	alert_sid.log	db2diag.log	USE master	show log_directory ;	pg.log,servermgr.log
			GO	pg_log
			xp_readerrorlog 0, 1, N'Logging SQL Server messages in file', NULL, NULL, N'asc'
Monitoring	Grid/OEM			pgwatch,Open PostgreSQL Monitoring (OPM)	nzportal
High availability	RAC/DG/ADG	HADR	MS cluter/Mirroring	PGCluster is a multi-master and synchronous replication tool	OS cluster/replication
database backup	rman>backup database ;	QUIESCE DATABASE IMMEDIATE FORCE CONNECTIONS;BACKUP DB <db>  TO "/home/offline_full"  COMPRESS;	BACKUP DATABASE [db] TO  DISK = 'F\db_backup_2015_09_02_210001_2075068.bak' WITH NOFORMAT, NOINIT,  NAME = N'db_delete-Full Database Backup', SKIP, NOREWIND, NOUNLOAD,  STATS = 10	pg_dump -U {user-name} {source_db} -f {dumpfilename.sql}	nzbackup -dir /home/user/backups -u user -pw password -db db1
database restore	rman>restore database	RESTORE DB <db>  FROM "/backup/offline_full"  TAKEN AT <timestamp>  INTO <db2>;	RESTORE DATABASE [db] FROM  DISK = 'F\db_.bak' WITH  FILE = 1,  NOUNLOAD,  STATS = 10	$ psql -U {user-name} -d {desintation_db}-f {dumpfilename.sql}	nzrestore -db db1 -u user -pw password -dir /home/user/backups -v
current Db connections	select * from v$session;	db2 list application all;	sp_who2	SELECT usesysid, usename FROM pg_stat_activity;	nzsession
super user	sys,system	SYSADM, SYSCTRL	SA,SYSADMIN	postgres(OS)	NZ(os user) SYSTEM DB usr
Db config files	init.ora/spfile	db2cfg,dbmcfg
Db files	ctl,redo,data	container data	data,log		NO TBS/everything in DISK