Neoview SQL Reference Manual (R2.5)

DescriptionData TypeColumn Name
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;
MODULE_NAME STATEMENT_NAME
PLAN_ID SEQ_NUM OPERATOR LEFT_CHILD_SEQ_NUM
RIGHT_CHILD_SEQ_NUM TNAME CARDINALITY
OPERATOR_COST TOTAL_COST DETAIL_COST
DESCRIPTION
------------------------------------------------------------ --------------------------------------------
---------------- -------------------- ----------- ------------------------------ ------------------ -
------------------ ------------------------------------------------------------ --------------- -------
-------- --------------- -------------------------------------------------------------------------------
----------------------------------------------------------------------------------------------------------
--------------- -------------------
? __EXPL_STMT_NAME__
212141478299499838 1 FILE_SCAN ? ?
NEO.USR.REGION 1.0000000E+002 9.2547051E-
003 9.2547051E-003 CPU_TIME:= 0.000374705 IO_TIME:= 0.00888 MSG_TIME:= 0 IDLETIME:= 0 PROBES:= 1
max_card_est: 100 fragment_id: 2 parent_frag: 0 fragment_type: dp2 scan_type: full scan of table
NEO.USR.REGION scan_direction: forward lock_state: cursor consistency_level: read_committed
columns_retrieved: 3 fast_scan: used fast_replydata_move: used key_columns: R_KEY begin_key: (R_KEY = <min>)
end_key: (R_KEY = <max>)
? __EXPL_STMT_NAME__
212141478299499838 2 PARTITION_ACCESS 1 ?
1.0000000E+002 6.8757636E-
004 9.9422819E-003 CPU_TIME:= 0.00106228 IO_TIME:= 0.00888 MSG_TIME:= 0 IDLETIME:= 0 PROBES:= 1
max_card_est: 100 fragment_id: 2 parent_frag: 0 fragment_type: dp2 buffer_size: 31000
record_length: 306 space_usage: 5:32:100:144 bottom_node_map: (\THE0105:13)
? __EXPL_STMT_NAME__
212141478299499838 3 ROOT 2 ?
1.0000000E+002 3.7297573E-
005 9.9795795E-003 CPU_TIME:= 0.00109958 IO_TIME:= 0.00888 MSG_TIME:= 0 IDLETIME:= 0.098 PROBES:= 1
max_card_est: 100 fragment_id: 0 parent_frag: (none) fragment_type: master statement: select *
from region; xn_access_mode: read_only xn_autoabort_interval: 0 auto_query_retry: enabled plan_version:
2400 SESSION_USERNAME: MXID01010130744212141209524355662000000044209superuser00 LDAP_USERNAME: superuser
NVCI_PROCESS: ON SHOWCONTROL_UNEXTERNALIZED_ATTRS: OFF SCHEMA: USR GENERATE_EXPLAIN: ON select_list:
NEO.USR.REGION.R_KEY, NEO.USR.REGION.R_NAME, NEO.USR.REGION.R_COMMENT
*** SQL operation complete.
EXPLAIN Statement 131