EXPLAIN¶
The EXPLAIN command shows the logical and physical execution plan for the specified SQL statement.
See the Reading Explain Plans page for more information on how to interpret these plans.
EXPLAIN [ANALYZE] [VERBOSE] statement
EXPLAIN¶
Shows the execution plan of a statement.
If you need more detailed output, use EXPLAIN VERBOSE.
EXPLAIN SELECT SUM(x) FROM table GROUP BY b;
+---------------+----------------------------------------------------------------------------------------------------------------------------------------------------------------+
| plan_type | plan |
+---------------+----------------------------------------------------------------------------------------------------------------------------------------------------------------+
| logical_plan | Projection: #SUM(table.x) |
| | Aggregate: groupBy=[[#table.b]], aggr=[[SUM(#table.x)]] |
| | TableScan: table projection=[x, b] |
| physical_plan | ProjectionExec: expr=[SUM(table.x)@1 as SUM(table.x)] |
| | AggregateExec: mode=FinalPartitioned, gby=[b@0 as b], aggr=[SUM(table.x)] |
| | CoalesceBatchesExec: target_batch_size=4096 |
| | RepartitionExec: partitioning=Hash([Column { name: "b", index: 0 }], 16) |
| | AggregateExec: mode=Partial, gby=[b@1 as b], aggr=[SUM(table.x)] |
| | RepartitionExec: partitioning=RoundRobinBatch(16) |
| | CsvExec: file_groups={1 group: [[/tmp/table.csv]]}, projection=[x, b], has_header=false |
| | |
+---------------+----------------------------------------------------------------------------------------------------------------------------------------------------------------+
EXPLAIN ANALYZE¶
Shows the execution plan and metrics of a statement.
If you need more information output, use EXPLAIN ANALYZE VERBOSE.
EXPLAIN ANALYZE SELECT SUM(x) FROM table GROUP BY b;
+-------------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------+
| plan_type | plan |
+-------------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------+
| Plan with Metrics | CoalescePartitionsExec, metrics=[] |
| | ProjectionExec: expr=[SUM(table.x)@1 as SUM(x)], metrics=[] |
| | HashAggregateExec: mode=FinalPartitioned, gby=[b@0 as b], aggr=[SUM(x)], metrics=[outputRows=2] |
| | CoalesceBatchesExec: target_batch_size=4096, metrics=[] |
| | RepartitionExec: partitioning=Hash([Column { name: "b", index: 0 }], 16), metrics=[sendTime=839560, fetchTime=122528525, repartitionTime=5327877] |
| | HashAggregateExec: mode=Partial, gby=[b@1 as b], aggr=[SUM(x)], metrics=[outputRows=2] |
| | RepartitionExec: partitioning=RoundRobinBatch(16), metrics=[fetchTime=5660489, repartitionTime=0, sendTime=8012] |
| | CsvExec: file_groups={1 group: [[/tmp/table.csv]]}, has_header=false, metrics=[] |
+-------------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------+