E Oracle Database Differences on Windows and UNIX

Learn about the differences between Oracle Database on Windows and UNIX. For Oracle Database developers and database administrators moving from a UNIX platform to Windows, this information can be helpful in understanding Windows features that are relevant to Oracle Database.

• Automatic Startup and Shutdown
  On UNIX, several files and scripts in different directories are used to start an instance automatically.
• Background Processing and Batch Jobs
  UNIX provides sophisticated control mechanisms for background processing and batch jobs.
• Diagnostic and Tuning Utilities
  On UNIX, utilities such as sar and vmstat are used to monitor Oracle Database background and shadow processes.
• Direct Writes to Disk
  On both UNIX and Windows platforms, bypassing the file system buffer cache ensures data is written to disk.
• Dynamic Link Libraries (DLLs)
  Shared libraries on UNIX are similar to shared DLLs on Windows.
• Hot Backups
  A (manual) hot backup is equivalent to backing up a tablespace that is in an offline backup mode.
• Initialization Parameters: Multiple Database Writers
  On UNIX, you can specify many database writer process with initialization parameter DB_WRITERS.
• Installation Accounts and Groups
  UNIX uses the concept of a DBA group. The root account cannot be used to install Oracle Database.
• Oracle Database Installation
  The following manual setup tasks, all required on UNIX, are not required on Windows:
• Memory Resources
  The resources provided by the UNIX default kernels are often inadequate for a medium or large instance of Oracle Database.
• Microsoft Transaction Server
  Windows coordinates distributed transactions through the Microsoft Distributed Transaction Coordinator (DTC), one of the components of Microsoft Transaction Server.
• Multiple Oracle Homes and OFA
  The goal of OFA is to place all Oracle Database software under one ORACLE_HOME directory and to spread database files across different physical drives as databases increase in size.
• Oracle Home User and Oracle User
  On Linux and UNIX systems, you must create and use a software owner user account (oracle), and this user must belong to the Oracle Inventory group (oinstall) and also must be a member of the appropriate OSDBA, OSOPER, OSBACKUPDBA, OSDGDBA, and OSKMDBA groups.
• Processes and Threads
  On UNIX, starting with Oracle Database 12c Release 2 (12.2), Oracle Database can use an operating system process or an operating system thread to implement each background task such as database writer (DBW0), log writer (LGWR), shared server process dispatchers, and shared servers.
• Raw Partitions
  Data files for tablespaces may be stored on a file system or on raw partitions.
• Windows Services
  Windows services are similar to UNIX daemons.