This
node represents table scans.
Node name: TBSCAN
Represents: A
table scan (relation scan) that retrieves rows by reading all the
required data directly from the data pages.
This type of scan
is chosen by the optimizer over an index scan when:
- The range
of values scanned occurs frequently (that is, most of
the table must be accessed)
- The table is small
- Index
clustering is low
- An index does not exist