Performance Improvement Tips for Oracle on UNIX

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TIMED_STATISTICS = true

tkprof EXPLAIN=username/passwd

      SQL statement is using indexes correctly.  Refer to DBA guide for a list

      of rules that the oracle optimizer uses when choosing a path for a SQL statement. 

                 <<<<<< OUTPUT OF TKPROF FILE  >>>>>>> 

count   = number of times OPI procedure was executed 

cpu     = cpu time executing in hundredths of seconds 

elap    = elapsed time executing in hundredths of secs 

phys    = number of physical reads of buffers (from disk) 

cr      = number of buffers gotten for consistent read 

cur     = number of buffers gotten in current mode (usually for update) 

rows    = number of rows processed by the OPI call 

===========================================================

select * from emp where empno=7369  

            count     cpu    elap    phys      cr     cur    rows 

Parse:          1       0       0       0       0       0 

Execute:        1       0       0       0       0       2       0 

Fetch:          1       0       0     219     227       0       2 

Execution plan: 

TABLE ACCESS (FULL) OF EMP 

===========================================================

select empno from emp where empno=7934  

            count     cpu    elap    phys      cr     cur    rows 

Parse:          2       0       0       0       0       0 

Execute:        2       0       0       0       0       2       0 

Fetch:          2       0       0       0&nb