Operators describe how SQL Server executes a query or a Data Manipulation Language (DML) statement. The query optimizer uses operators to build a query plan to create the result specified in the query, or to perform the operation specified in the DML statement. The query plan is a tree consisting of physical operators.

This is the table of descriptions to be used in the properties dialog showing the operator details in the execution plan graphical view.

Operator

Graphical execution plan icon

Text

Aggregate

None

The Aggregate operator is a physical or logical operator that computes a new value using the SQL Server functions MIN, MAX, SUM, COUNT or AVG.

Arithmetic Expression

The Arithmetic Expression operator computes a new value from existing values in a row.  Arithmetic Expression is not used in SQL Server 2014.

Assert

The Assert operator verifies a condition.  The Assert operator is a physical operator.

Assign

The Assign operator assigns a value to a variable

Asnyc Concat

None

The  Asnyc Concat operator is used in remote distributed queries to get output rows from remote child nodes to send to the parent node.

Bitmap

The Bitmap operator is used to apply filtering to parallel query plans.  Bitmap is a physical operator.

Bitmap Create

The Bitmap Create operator is a logical operator that shows where bitmaps are built.

Bookmark Lookup

The Bookmark Lookup operator uses a bookmark (row ID or clustering key) to look up the corresponding row in the table or clustered index.  Bookmark Lookup is not used in SQL Server 2014. The Key Lookup operator also provides this functionality.

Branch Repartition

None

The Branch Repartition operator is a logical operator showing where iterators could be executed by parallel threads.

Broadcast

None

The Broadcast operator sends the set of input rows to multiple consumers.

Build Hash

The Build Hash operator indicates that a batch has table has been built.

Cache

None

The Cache operator is a logical operator that caches a single row of data.  Cache is not used in SQL Server 2014.

Clustered Index Delete

The Clustered Index Delete operator deletes rows from a clustered index.  Clustered Index Delete is a physical operator.

Clustered Index Insert

The Clustered Index Insert operator inserts rows into a clustered index.  Clustered Index Insert is a physical operator.

Clustered Index Merge

The Clustered Index Merge operator merges a data stream and a clustered index.  Clustered Index Merge is a physical operator.

Clustered Index Scan

The Clustered Index Scan operator scans a clustered index. It returns only rows matching the WHERE clause and sorts the results based on the ORDERED clause.

Clustered Index Seek

The Clustered Index Seek operator retrieves rows from a clustered index using the seeking ability of indexes.

Clustered Index Update

The Clustered Index Update operator updates rows in the clustered index. It only updates rows matching the WHERE clause.

Collapse

The Collapse operator merges separate operations into a single more efficient operation.

Columnstore Index Scan

The Columnstore Index Scan operator scans the columnstore index specified in the query execution plan argument.

Compute Scalar

The Compute Scalar operator returns a computer scalar value from an evaluated expression.

Concatenation

The Concatenation operator returns rows scanned from multiple inputs. This is used for statements like UNION ALL.

Constant Scan

The Constant Scan operator adds rows into a query.

Convert

The Convert operator converts one scalar type to another.

Cross Join

None

The Cross Join operator is a logical operator that joins each row from input with each row from another input.

catchall

The catchall operator is a placeholder icon when an operator does not match any other query operators.

Cursor

None

The Cursor operator describes the execution of a query or update that use cursor operations.

Declare

The Declare operator allocates a local variable.

Delete

The Delete operator deletes rows from an object.

Deleted Scan

The Deleted Scan operator scans the deleted table within a trigger.

Distinct

None

The Distinct operator removes duplicate rows.

Distinct Sort

None

The Distinct Sort operator removes duplicate rows and sorts the resulting set of rows.

Distribute Streams

The Distribute Streams operator is used to break records from a single input to multiple output streams in a parallel query plan.

Dynamic

The Dynamic operator uses a cursor to see all changes made by others.

Eager Spool

The Eager Spool operator stores each row in the input to tempdb so that this cached data can be used if the operator is rewound.

Fetch Query

The Fetch Query operator returns rows from a fetch issued against a cursor.

Filter

The Filter operator returns only rows that match a filter expression.

Flow Distinct

None

The Flow Distinct operator removes duplicate rows but returns each row as it is processed.

Full Outer Join

None

The  Full Outer Join operator is a logical operator that implements an OUTER JOIN. Results in all matching rows from two streams plus rows for each row in the streams that did not have matches.

Gather Streams

The Gather Streams operator is used to consume multiple input streams and combine them into a single output stream in parallel query plans.

Hash Match

The Has Match operator creates a hash table from the rows in the build input.

Inner Join

None

The Inned Join operator returns rows that satisfy the JOIN of the first (top) input with the second (bottom) input.

Insert

The Insert logical operator inserts input rows into the object specified in the Argument column.

Inserted Scan

The Inserted Scan operator scans the inserted table.

Intrinsic

The Intrinsic operator runs an internal Transact-SQL function.

Iterator

The Iterator operator is a placeholder icon used when no match is found for the iterator operation.

Key Lookup

The KEY LOOKUP operator signals a lookup using a bookmark on a table with a clustered index.

Keyset

The KEYSET operator uses a cursor that can only see updates and not inserts.

Language Element

The LANGUAGE ELEMENT operator is a placeholder icon when no matching language constructs can be found.

Lazy Spool

The LAZY SPOOL operator stores each row in the input to tempdb so that this cached data can be used if the operator is rewound. The rows are only copied to tempdb as they are processed.

Left Anti Semi Join

None

The LEFT ANTI SEMI JOIN operator returns rows from the first input where there is no match in the second input.

Left Outer Join

None

The LEFT OUTER JOIN operator returns rows from the first input that satisfy the join with the second input.

Left Semi Join

None

The LEFT SEMI JOIN operator returns rows from the first input that have a match with the second input.

Log Row Scan

The LOG ROW SCAN operator scans the transaction log.

Merge Interval

The MERGE INTERVAL operator merges multiple intervals to create a minimal set of non-overlapping intervals.

Merge Join

The MERGE JOIN operator performs one of the many possible join operations.

Nested Loops

The NESTED LOOPS operator perform the logical operations to satisfy many join operations that need a loop to search the inner table for rows in the outer table.

Nonclustered Index Delete

The NONCLUSTERED INDEX DELETE operator deleted rows from a non-clustered index.

Index Insert

The INDEX INSERT operator inserts rows into a non-clustered index.

Index Scan

The INDEX SCAN operator scans a non-clustered index. It returns only rows matching the WHERE clause

Index Seek

The INDEX SEEK operator retrieves rows from a non-clustered index using the seeking ability of indexes.

Index Spool

The INDEX SPOOL operator copies input rows to tempdb and builds a non-clustered index for these rows.

Nonclustered Index Update

The NONCLUSTERED INDEX UPDATE operator updates rows from its input in the non-clustered index.

Online Index Insert

The ONLINE INDEX INSERT operator is a physical operator indicating that an index create, alter or drop is performed online.

Parallelism

None

The PARALLELISM operator the logical operations of distribute, gather or repartition streams.

Parameter Table Scan

The PARAMETER TABLE SCAN operator scans a table that acts as a parameter of the query.

Partial Aggregate

None

The PARTIAL AGGREGATE operator is a logical operator that aggregates input rows to prevent writing to disk in parallel plans.

Population Query

The POPULATION QUERY operator populates a cursor's work table.

Refresh Query

The REFRESH QUERY operator fetches current data for rows.

Remote Delete

The REMOTE DELETE operator deletes rows from an remote object.

Remote Index Scan

The REMOTE INDEX SCAN operator scans a remote index.

Remote Index Seek

The REMOTE INDEX SEEK operator retrieves rows using a remote index.

Remote Insert

The REMOTE INSERT operator inserts rows into a remote object.

Remote Query

The REMOTE QUERY operator submits a query to a remote source.

Remote Scan

The REMOTE SCAN operator scans a remote object.

Remote Update

The REMOTE UPDATE operator updates a remote object.

Repartition Streams

The REPARTITION STREAMS operator creates multiple out streams from multiple input streams while applying a bitmap filter.

Result

The RESULT operator is the query plan return data.

RID Lookup

The RID LOOKUP operator is a bookmark lookup on a heap.

Right Anti Semi Join

None

The RIGHT ANTI SEMI JOIN operator returns rows from the second input where the is no match in the first input.

Right Outer Join

None

The RIGHT OUTER JOIN operator returns rows from the second input that satisfy the join with the first input.

Right Semi Join

None

The RIGHT SEMI JOIN operator returns rows from the second input that have a match with the first input.

Row Count Spool

The ROW COUNT SPOOL operator returns empty rows for each row in the input stream.

Segment

The SEGMENT operator uses the value of columns to divide the input set into segments.

Segment Repartition

None

The SEGMENT REPARTITION operator marks the boundaries of regions whose iterators can be run in parallel threads.

Sequence

The SEQUENCE operator executes each input in sequence.

Sequence Project

The SEQUENCE PROJECT operator adds columns to the input set, divides the input set into segments and outputs one segment at a time.

Snapshot

The SNAPSHOT operator creates a cursor that cant see changes by others.

Sort

The SORT operator sorts incoming rows.

Split

The SPLIT operator creates a delete and insert operation out of each update operation.

Spool

The SPOOL operator saves an intermediate query to tempdb.

Stream Aggregate

The STREAM AGGREGATE operator groups rows by columns and calculates aggregate expressions.

Switch

The SWITCH operator copies the appropriate input stream to the output stream by evaluating an expression.

Table Delete

The TABLE DELETE operator deletes rows from a table.

Table Insert

The TABLE INSERT operator inserts rows into a table.

Table Merge

The TABLE MERGE operator applies a merge data stream to a heap.

Table Scan

The TABLE SCAN operator retrieves rows from a table.

Table Spool

The TABLE SPOOL operator scans the input and places the rows into tempdb.

Table Update

The TABLE UPDATE operator updates rows in a table.

Table-valued Function

The TABLE-VALUED FUNCTION operator evaluates a table-valued function and stores the resulting rows in tempdb.

Top

The TOP operator returns only the specified number of rows from the input.

Top N Sort

None

The TOP N SORT operator returns only the specified number of rows from the input and sorts them.

UDX

The UDX operator implements XQuery and XPath operations.

Union

None

The UNION operator combines multiple inputs and removes duplicates.

Update

The UPDATE operator updates a specified object from the rows in its input.

While

The WHILE operator represents a SQL while loop.

Window Spool

The WINDOW SPOOL operator expands the input rows into sets of rows that represent the window associated with the row.



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