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Table 2-5 Node Listing Information
Field
Operator name
SEQ_NO
Children information
TABLE_NAME
REQUESTS_IN
ROWS_OUT or ROWS/REQUEST
EST_OPER_COST
EST_TOTAL_COST
DESCRIPTION
This example uses OPTIONS 'n':
>>explain options 'n' select * from region;
------------------------------------------------------------------ PLAN SUMMARY
MODULE_NAME .............. DYNAMICALLY COMPILED
STATEMENT_NAME ........... NOT NAMED
PLAN_ID .................. 212141478299499838
ROWS_OUT ............... 100
EST_TOTAL_COST ........... 0.01
STATEMENT ................ select * from region;
------------------------------------------------------------------ NODE LISTING
ROOT ======================================
REQUESTS_IN .............. (not found)
ROWS_OUT ............... 100
EST_OPER_COST ............ 0.01
EST_TOTAL_COST ........... 0.01
DESCRIPTION
max_card_est ......... 100
fragment_id ............ 0
parent_frag ............ (none)
fragment_type .......... master
xn_access_mode ......... read_only
xn_autoabort_interval
auto_query_retry ....... enabled
plan_version ....... 2,400
SESSION_USERNAME ....... MXID01010130744212141209524355662000000044209superus
LDAP_USERNAME .......... superuser
NVCI_PROCESS ........... ON
SHOWCONTROL_UNEXTERNALI
SCHEMA ................. USR
GENERATE_EXPLAIN ....... ON
select_list ............ NEO.USR.REGION.R_KEY, NEO.USR.REGION.R_NAME,
Description
Current operator type, such as FILE_SCAN, HASH_JOIN, NESTED_JOIN,
and so on.
Sequence number of the current operator in the query execution plan;
indicates the sequence in which the query plan is generated.
Sequence number of the operator's children (operators that feed data up to
this operator). There can be 0, 1, or 2 children shown as NO CHILDREN,
ONLY CHILD 6, or CHILDREN 5, 7.
Name of base table, shown only on operators that access the table.
Estimated number of requests for execution of this operator. The value is 1
except for the right child operator (inner scan) of a nested-loop join.
Estimated number of rows returned by the plan or, when REQUESTS_IN is
greater than one, the value is the estimated number of rows returned per
input request.
Estimated cost associated with executing the current operator.
Estimated cost associated with execution of the current operator and all
children.
Additional information about the operation. For example, in the case of a
scan, the description field shows scan_type, scan_direction, lock_mode,
access_mode, columns_retrieved, optimization information, and so on. For
details about all operators and their description fields, see the Neoview Query
Guide.
SEQ_NO 3
0
er00
OFF
NEO.USR.REGION.R_COMMENT
ONLY CHILD 2
EXPLAIN Statement
127
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