1.1

DescriptionQuery Plan Code
An INTERSECT, INTERSECT ALL, or INTERSECT DISTINCT
operation. See SQL Language Limitations on page 687.
INTERSECT
The time spend for a left or right hash outer join operation.LOHASHJOIN
The time spend for a left or right nested loop outer join operation.LONLJOIN
The time spent on a merge join operation.MERGEJOIN
The time taken to perform a nested loop join (matching all of the left
table rows with the right table rows in a query).
NLJOIN always has two nested entries. The first entry corresponds
to the outer table, which is read once and returns some number (n)
NLJOIN
of rows. The second entry corresponds to the inner table which is
iterated over n times (once for each result in the outer table).
The individual seeks for the inner and outer tables are timed
separately and are listed in each nested entry.
Example Query Plan Analysis on page 268 describes an example
query plan that performs an NLJOIN.
A predicate filtering operation that occurs while extracting columns
(PROJECTION operation).
PROJECT-FILTER
The time spent to extract the selected columns from the base row of
the table. This code can appear multiple times for a query depending
on how the engine processes the query.
PROJECTION
QUERY-RECEIVE is the top-level code that organizes all tasks
associated with processing a query on a specific data store member.
QUERY-RECEIVE
QUERY-RECEIVE displays the member ID and process ID of the
data store, as well as the total aggregate time for all of the subordinate
tasks. If the query was distributed to multiple data store members,
then each member displays a separate QUERY-RECEIVE code. The
contents of multiple QUERY-RECEIVE codes are similar unless
tables are partitioned across different VMs or physical machines.
This value is linked to the RESULT-HOLDER code on the query
coordinator. All of the tasks beneath RESULT-HOLDER represent
query operators performed on the data store member.
RESULT-HOLDER
The network time that was spent sending result rows back to the
query coordinator. The target node is the query coordinator.
RESULT-SEND
The time spent processing results for the FETCH clause.ROW-COUNT
The total time spent for index entries to fetch the base row from the
table. This occurs when the projection of the query is different from
the index column.
ROWIDSCAN
Indicates a set operation (a UNION, UNION ALL, UNION
DISTINCT, INTERSECT, INTERSECT ALL, INTERSECT
SET
DISTINCT, EXCEPT, EXCEPT ALL, or EXCEPT DISTINCT
operation). See SQL Language Limitations on page 687.
A scroll insensitive cursor operation.SCROLL-INSENSITIVE
The time spent sorting rows to execute an ORDER BY, DISTINCT,
or GROUP BY clause.
SORT
The time required to scan a table.TABLESCAN
The time spent performing a UNION, UNION ALL, or UNION
DISTINCT operation of two queries. See SQL Language Limitations
on page 687.
UNION
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Evaluating Query Plans and Query Statistics