SQL> explain plan for select * from dept where rowid = ':x';
Execution Plan
----------------------------------------------------------
0SELECT STATEMENT Optimizer=CHOOSE (Cost=1 Card=1 Bytes=18)
10 TABLE ACCESS (BY USER ROWID) OF 'DEPT' (Cost=1 Card=1 Bytes=18)
Cost = (
#SRds * sreadtim +
#MRds * mreadtim +
#CPUCycles / cpuspeed
) / sreadtim
where
#SRDs - number of single block reads
#MRDs - number of multi block reads
#CPUCycles - number of CPU Cycles
sreadtim - single block read time
mreadtim - multi block read time
cpuspeed - CPU cycles per second
