Oracle Database Administration

Database Troubleshooting Assessing database availability issues quickly • Identifying system performance issues with OS utilities • Querying data dictionary views to display resource-intensive SQL statements • Using Oracle performance tools to identify resource-consuming SQL statements • Identifying and resolving locking issues • Troubleshooting open-cursor issues • Investigating issues with the undo and temporary tablespaces 1.Checking Database Availability 2.Investigating Disk Fullness 3.Identifying System Bottlenecks When inspecting the end of the alert.log, look for errors that indicate these types of issues: Archiver pr • ocess hung, owing to inadequate disk space • File system out of space • Tablespace out of space • Running out of memory in the buffer cache or shared pool    Media error indicating that a data file is missing or damaged • Error indicating an issue with writing an archive redo log; Using vmstat The vmstat utility displays real-...

check linux kernel version number uname -r uname -a $ cat /proc/version cat /etc/*release uname -m uname -ar  check the database status select name,open_mode,database_name,created,log_mode,platform_name,from v$database; Check the object's invalid SELECT owner,COUNT(*) FROM dba_objects WHERE status = 'INVALID' GROUP BY owner select count(*) from dba_objects  WHERE status ='INVALID'; check opatch version opatch -v $ORACLE_HOME/OPatch/opatch version opatch lsinventory -bugs_fixed | egrep -i 'PSU|DATABASE PATCH SET UPDATE' check oraInst.loc file pointing to your current $ORACLE_HOME or not. check free space on $ORACLE_HOME  export opatch  export PATH=$PATH:$HOME:$ORACLE_HOME/OPatch:/bin export PATH=$PATH:$ORACLE_HOME/OPatch opatch lsinventory apply patch check logs vi $ORACLE_BASE/cfgtoollogs/catbundle/catbundle_PSU__APPLY_.log vi $ORACLE_BASE/cfgtoollogs/catbundle/catbundle_PSU__GENERATE_.log count invalid objects SELECT ...