cd alertlogdirectory;
grep ORA- alertSID.log

grep userid /etc/passwd

grep 1521 /etc/services

tail -20 alertSID.log

head -20 alertSID.log

find /usr/oracle -name whereare.you -print

find /usr/oracle -name "*.tmp" -print -exec rm -f {} \;

find /usr/oracle -mtime +7 -print

find /usr/oracle -mtime -7 -print

find /usr/oracle -size +1048576c -name "*.dmp" -print -exec compress {} \;

ipcs -mb

df -k /oracle

who -T

passwd oracle

tr "[a-z]" "[A-Z]" < filename > newfilename

tr "[A-Z]" "[a-z]" < filename > newfilename

kill unixid
OR
kill -9 unixid

ps -ef | grep SIDNAME

wc -l filename

sed 's/SCOTT/TIGER/g' filename > newfilename

head -120 filename | tail -20

rm filename; touch filename

tnsping SIDNAME

ping servername
OR
ping IPADDRESS

$ORACLE_HOME/orainst/inspdver

DO YOU KNOW....
You can give permissions for all users to read the trace files generated by Oracle7 (in USER_DUMP_DEST directory) by including the parameter _TRACE_FILES_PUBLIC = TRUE in init.ora file and cycle the database (note the parameter starts with "_" )