Neoview SQL Reference Manual (R2.4 SP2)

DescriptionData TypeColumn Name
For operators in scan group, full name of base table,
truncated on the right if too long for column. If
correlation name differs from table name, simple
correlation name first and then table name in
parentheses.
CHAR(60)TNAME
Estimated number of rows that are returned by the
current operator. Cardinality appears as
ROWS/REQUEST in some forms of EXPLAIN output.
For the right child of a nested join, multiply the
cardinality by the number of requests to get the total
number of rows produced by this operator.
REALCARDINALITY
Estimated cost associated with the current operator to
execute the operator.
REALOPERATOR_COST
Estimated cost associated with the current operator to
execute the operator, including the cost of all subtrees
in the operator tree.
REALTOTAL_COST
Cost vector of five items, which are described in detail
in the next table.
VARCHAR (200)DETAIL_COST
Additional information about the operator. For a
detailed look at all operators, see the Neoview Query
Guide.
VARCHAR (3000)DESCRIPTION
The DETAIL_COST column contains these cost factors:
Table 2-6 Cost Factors of DETAIL_COST column
An estimate of the number of seconds of processor time it might take to execute the
instructions for this operator. A value of 1.0 is 1 second.
CPU_TIME
An estimate of the number of seconds of I/O time (seeks plus data transfer) to perform
the I/O for this operator.
IO_TIME
An estimate of the number of seconds it takes for the messaging for this operator. The
estimate includes the time for the number of local and remote messages and the
amount of data sent.
MSG_TIME
An estimate of the number of seconds to wait for an event to happen. The estimate
includes the amount of time to open a table or start an ESP process.
IDLETIME
The number of times the operator will be executed. Usually, this value is 1, but it can
be greater when you have, for example, an inner scan of a nested-loop join.
PROBES
The following example has been edited to allow it to be displayed here (lines folded, trailing
blanks removed, and so on).
This example uses OPTIONS ‘m’:
>>explain options ‘m’ select * from region;
EXPLAIN Statement 129