Add documentation for EXPLAIN ANALYZE VERBOSE mode
@@ -7,7 +7,7 @@ Synopsis
.. code-block:: none
- EXPLAIN ANALYZE statement
+ EXPLAIN ANALYZE [VERBOSE] statement
Description
-----------
@@ -15,6 +15,9 @@ Description
Execute the statement and show the distributed execution plan of the statement
along with the cost of each operation.
+The ``VERBOSE`` option will give more detailed information and low-level statistics
+They may not be understandable for users not familiar with Presto internals and implementation details.
+
.. note::
The stats may not be entirely accurate, especially for queries that complete quickly.
@@ -69,6 +72,28 @@ relevant plan nodes). Such statistics are useful when one wants to detect data a
orderdate := tpch:orderdate
clerk := tpch:clerk
+When ``VERBOSE`` option is used, some operators may report additional information, e.g. for Window Function operator you may notice:
+
+.. code-block:: none
+
+ EXPLAIN ANALYZE VERBOSE SELECT count(clerk) OVER() FROM orders WHERE orderdate > date '1995-01-01';
+
+ Query Plan
+ -----------------------------------------------------------------------------------------------
+ ...
+ - Window[] => [clerk:varchar(15), count:bigint]
+ Cost: {rows: ?, bytes: ?}
+ CPU fraction: 75.93%, Output: 8130 rows (230.24kB)
+ Input avg.: 8130.00 lines, Input std.dev.: 0.00%
+ Active Drivers: [ 1 / 1 ]
+ Index size: std.dev.: 0.00 bytes , 0.00 rows
+ Index count per driver: std.dev.: 0.00
+ Rows per driver: std.dev.: 0.00
+ Size of partition: std.dev.: 0.00
+ count := count("clerk")
+ ...
+
+
See Also
--------
