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TiDB defines operations in a list.

Operation Category Reference Description
Aggregation Folder Link Aggregate data.
Apply Join Link A join algorithm.
Batch_Point_Get Producer Link It retrieves a range of data from an index.
ClusterMemTableReader Producer Link Scan data from cluster memory.
CTE Producer Link Scan the entire CTE.
CTEFullScan Producer Link Scan the entire CTE.
CTETable Producer Link CTE is a special data structure defined by TiDB as an intermediate representation.
DataSource Producer Link Unknown table scanning operation that never is observed in practice.
Delete Consumer Link Delete data.
ExchangeReceiver Executor Link Collect results.
ExchangeSender Executor Link Distribute tasks.
Exists Folder Link The equivalence to the keyword “EXISTS” in SQLs.
Foreign_Key_Cascade Consumer Link When a row is deleted from the referenced table, TiDB automatically deletes all rows from the referencing table that reference the deleted row. This is known as a cascading delete and is implemented by TiDB using the “Foreign_Key_Cascade” operator in its query plans.
Foreign_Key_Check Consumer Link Checking foreign key constraints during query execution.
HashAgg Folder Link Aggregate data by the hash aggregate algorithm.
HashJoin Join Link Join tables with the hash algorithm.
IndexFullScan Producer Link Scan indexes only.
IndexHashJoin Join Link A variant algorithm to join tables.
IndexJoin Join Link The index join is a variant of the nested loop join in database systems using the index.
IndexLookUp Executor Link Retrieve data from a secondary index.
IndexMerge Executor Link An optimization to merge the data from multiple index-scanned tables.
IndexMergeJoin Join Link INDEX-MERGE joins have multiple indexes satisfying the entire query.
IndexRangeScan Producer Link Index scans with the specified range.
IndexReader Executor Link Read the results from another computing node with indexes.
IndexScan Producer Link Scanning data via indexes.
Insert Consumer Link Insert data.
Join Join Link Unknown Join operation.
Limit Combinator Link Limit the number of returned rows.
LoadData Producer Link Unknown table scanning operation that never is observed in practice.
MaxOneRow Combinator Link At most one row is returned.
MemTableScan Producer Link Scan the data in the memory.
MergeJoin Join Link Join tables with merge algorithm.
PartitionUnion Combinator Link Union tables using partitions.
Point_Get Producer Link It retrieves a single row of data from an index using the primary key or a unique secondary index.
Projection Projector Link Return specific columns.
Selection   Link This operator is equivalent to the filter property, so we map it to the property.
SelectLock Executor Link Lock target tables to guarantee transition consistency.
Set Executor Link Set environmental variables.
Show Executor Link Show internal variables.
ShowDDLJobs Executor Link Show DDL working status.
Shuffle Executor Link It shuffles data into other nodes for parallel computation.
ShuffleReceiver Executor Link It collects data from other parallel computing nodes.
Sort Combinator Link Sort rows.
StreamAgg Folder Link Aggregate ordered data by the stream aggregate algorithm.
TableDual Producer Link It returns a single row with no columns. It is often used as a placeholder or a source for default values in SQL statements.
TableFullScan Producer Link Full table scan
TableRangeScan Producer Link Table scans with the specified range
TableReader Executor Link Read the results from another computing node.
TableRowIDScan Producer Link Scans the table based on the RowID.
TableSample Producer Link Sample part data, instead of scanning all data of a table.
TableScan Producer Link Scan the full table.
TiKVSingleGather Executor Link It collects data from other parallel TiKV nodes.
TopN Combinator Link Sort rows and return top-N rows.
Union Combinator Link Union multiple tables.
UnionScan Producer Link Unknown scanning operation.
Update Consumer Link Update data.
Window Folder Link It uses a window function to calculate data.

References