1.1.1

DescriptionQuery Plan Code
RESULT-HOLDER is a blocking operation that is connected to
SEQUENTIAL-ITERATION.
The time required to merge results from an n-way merge.ROUNDROBIN-ITERATION
The time spent returning rows specified in a FETCH NEXT clause.
(See OFFSET and FETCH FIRST Clauses on page 535.)
ROW-COUNT-ITERATION
SEQUENTIAL-ITERATION is an operator that gathers results and
sends them to the client as the client requests, one block at a time.
SEQUENTIAL-ITERATION
This code shows the total aggregate row count of the query. If a
FETCH FIRST clause was used, it is displayed in this operator.
The following codes are shown only for data store members in a query plan:
DescriptionQuery Plan Code
An aggregate operation such as SUM, AVG, MIN, or MAX.AGGREGATION
The time spent on an index scan created from a table constraint.CONSTRAINTSCAN
An EXCEPT, EXCEPT ALL, or EXCEPT DISTINCT operation.
See SQL Language Limitations on page 707.
EXCEPT
A predicate filtering operation.FILTER
The time spent performing a global hash index scan (for example,
for reference checks).
GLOBALINDEXSCAN
Time spent grouping columns.GROUPBY
The time spent on a hash join operation.HASHJOIN
The time spent scanning a generated hash table.HASHSCAN
Time spent scanning GemFire regions.HEAP
If the query required a scan on an index, then this code indicates the
time required for the scan.
INDEXSCAN
An INTERSECT, INTERSECT ALL, or INTERSECT DISTINCT
operation. See SQL Language Limitations on page 707.
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 272 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
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Evaluating Query Plans and Query Statistics