Friends,

Could some one here explain me the significance of GENROW operator in an explain plan??

GENROW is a row constructor. Since everything(!) in SQL is a table, scalar values that have to be scanned must be converted to a table. Do you have a specific example? It may be easier to explain it with this.

Merge Into Cffs.addresser T1 Using (
Select Aun
From Cffs.client_addresser)t2 On T1.addressid=
T2.addressid
When Matched
Then
Update Set T1.addressdata=t2.addressdata, T1.lastwritten=
Current_timestamp, T1.versionno =1
When Not Matched
Then
Insert (t1.addressid, T1.countrycode, T1.modifiableind,
T1.addressdata, T1.addresslayouttype, T1.versionno,
T1.lastwritten)values(t2.addressid, 'us', '1',
T2.addressdata, 'us', 1 , Current_timestamp)

Hi Stolze,

Above is the example for which i see GENROW operator in explain plan

How about showing us the plan as well? Or do you expect us to figure out how your table looks like and which statistics you have at the moment?

What I can tell is that you have an INSERT statement in the THEN branch, and that INSERT contains a VALUES table constructor. So I would not be surprised to see a GENROW for this in the plan because it generates a row.

When you see "GENROW" in an access plan, it is a "generate row" step. It represents the creation of temporary row(s) for use in subsequent steps, and is not something you need to worry about.