Modern Oracle DBA

Redo log: Record all changes made a data It’s provide the recovery mechanism Redo log can be organized into groups Minimum two groups are required How Oracle write the Redo log:  LGWR write to redo log file in cycle method When the current redo log file fills LGWR writing next available redo log file Whenever a transaction was committed LGWR writes the transaction redo records from the redo log buffer ARCHIVELOG MODE If you have enabled archiving then the database cannot reuse or overwrite an active online log file until one of the archiver background processes (ARCn) has archived the file. NOARCHIVELOG MODE If archiving is disabled then when the last redo log file is full, LGWR continues by overwriting the first available active file. Redo log files are following stage: Current Active Inactive Current: The redo log file that LGWR is actively writing to is called the current redo log file Active: Redo log files

How to find database size? SQL> select sum(bytes)/1024/1024 from dba_data_files;                               (OR) SQL>select sum(result) from ( select 'dba_data_files',sum(bytes)/1024/1024/1024 result from dba_data_files union select 'dba_temp_files',sum(bytes)/1024/1024/1024 result from dba_temp_files); (OR) SELECT ROUND (SUM (used.bytes) / 1024 / 1024 / 1024) || ' GB' "Database Size",ROUND (SUM (used.bytes) / 1024 / 1024 / 1024) - ROUND (free.p / 1024 / 1024 / 1024)|| ' GB' "Used space", ROUND (free.p / 1024 / 1024 / 1024) || ' GB' "Free space" FROM (SELECT    bytes FROM v$datafile UNION ALL SELECT bytes FROM v$tempfile UNION ALL SELECT bytes FROM v$log) used, (SELECT SUM (bytes) AS p FROM dba_free_space)free GROUP BY free.p; How to find Schema size? SQL> select sum(bytes)/1024/1024 from dba_segments where OWNER='SCOTT'; How to find tablespace size

Step 1: Check the patch applied are not: SQL> select bug_number from ad_bugs where bug_number = 'Patch_number'; Step 2: Download the patch Step 3: Unzip the patch. And set the permission Step 4: Down the Application services Step 5: Enable the Maintenance Mode Choice option 5 Choice option 1 Enable maintenance mode Step 6: Run adpatch Step 7: Once patch was completed   Disable maintenance mode   [appltest@devserver]$ adadmin           AD Administration Main Menu    --------------------------------------------------    1.    Generate Applications Files menu    2.    Maintain Applications Files menu    3.    Compile/Reload Applications Database Entities menu    4.    Maintain Applications Database Entities menu    5.    Change Maintenance Mode    6.    Exit AD Administration Enter your choice [6] : 5 Disable Mantainance

Overview of FNDLOAD in R12.2   FNDLOAD is a Concurrent Program that allows the moving of Metadata from one instance to another instance. The loader operates in one of two modes: download or upload. In the download mode, data is downloaded from the database to a text file. in the upload mode data is uploaded from a text file to the database.  The Generic Loader downloads data from a database according to a configuration (.lct) file and converts the data into a data file (.ldt file). The Generic Loader can then upload this data to another database using a configuration file.  It allows downloading of Metadata directly via a OS command and then can be moved and uploaded to another instance. What is LCT and LDT files? LCT: Loader configuration file LDT: Loader data file format Create .ldt files Concurrent Program LDT FNDLOAD apps/pwd 0 Y UPLOAD $FND_TOP/patch/115/import/afcpprog.lct $JA_TOP/patch/115/import/US/jai121cp.ldt - CUSTOM_MODE=FORCE Value