Oracle Database

Find Oracle Archive Logs Older Than N Days with find -mtime Purpose Oracle databases in archivelog mode write a stream of .ARC (archived redo log) files to a destination directory. The directory fills up. When it fills up, the database hangs. The four find -mtime commands below let a DBA list, delete, compress, or move …

Write Text Files from Oracle PL/SQL with UTL_FILE Example Purpose UTL_FILE is the built-in Oracle PL/SQL package for reading and writing operating-system files from inside the database. The procedure below — taken straight from the shutdownabort.com DBA Quick Guides (Andrew Barry, 2007–2013, preserved via the Wayback …

Sample tnsnames.ora Dedicated Server Entry (with ASM) Purpose The tnsnames.ora file is the client-side address book for Oracle Net. Each entry maps a short alias (SCR9) to a full network address — protocol, host, port, and target service. Without a working tnsnames.ora entry, sqlplus, rman, and any application using …

Sample listener.ora with Static SID_LIST and Extproc Purpose The listener.ora file is the server-side configuration for the Oracle Net listener — the process that accepts incoming client connections and hands them off to a database server process. The sample below — taken straight from the shutdownabort.com DBA Quick …

Delete the 500 Oldest Files in a Directory (Oracle DBA) Purpose Oracle's diagnostic destination (DIAGNOSTIC_DEST), audit file destination (AUDIT_FILE_DEST, also known as adump), and per-process trace directories collect thousands of small files over time. Inode counts, not bytes, are usually the limit that bites first …

List Files Opened by an Oracle Process with lsof -p Purpose lsof (LiSt Open Files) is the UNIX tool for inspecting which processes have which files open. For an Oracle DBA it is the fastest answer to four common questions: which datafiles is this server process touching, which trace file is PMON writing into right now, …

Oracle Flashback Query: Copy Historical Data Into a New Table Sometimes you need to go back in time and recover data the way it looked at a specific moment — without restoring the full database. Oracle makes this possible with Flashback Query, using the AS OF TIMESTAMP clause to read historical data directly from the …

Oracle RMAN REPORT SCHEMA Command: Display Database Files Purpose The REPORT SCHEMA command is an essential Oracle RMAN (Recovery Manager) tool that displays comprehensive information about all database files in your Oracle database. This command provides database administrators with a quick view of the current …

Oracle RMAN Report Obsolete Redundancy Command Guide Purpose The report obsolete redundancy = 2 command in Oracle Recovery Manager (RMAN) identifies database backups that are no longer necessary for recovery operations based on a redundancy-based retention policy. This command helps database administrators determine …

Oracle RMAN List Backup of Database Command Purpose The LIST BACKUP OF DATABASE command is an Oracle Recovery Manager (RMAN) utility that displays all existing database backups stored in the RMAN repository. This command helps database administrators verify backup availability, review backup history, and plan recovery …