Add docs for explain distributed json plan

trinodb · Aug 26, 2022 · d0563dc · d0563dc
1 parent 114435c
commit d0563dc
Showing 1 changed file with 203 additions and 0 deletions.
diff --git a/docs/src/main/sphinx/sql/explain.rst b/docs/src/main/sphinx/sql/explain.rst
@@ -399,6 +399,209 @@ Distributed plan::
                    Estimates: {rows: 25 (225B), cpu: 225, memory: 0B, network: 0B}
                    regionkey := tpch:regionkey
 
+EXPLAIN (TYPE DISTRIBUTED, FORMAT JSON)
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+.. warning:: The output format is not guaranteed to be backward compatible across Trino versions.
+
+JSON Distributed plan::
+
+    EXPLAIN (TYPE DISTRIBUTED, FORMAT JSON) SELECT regionkey, count(*) FROM nation GROUP BY 1;
+
+.. code-block:: json
+
+    {
+       "0" : {
+          "id" : "9",
+          "name" : "Output",
+          "descriptor" : {
+             "columnNames" : "[regionkey, _col1]"
+          },
+          "outputs" : [ {
+             "symbol" : "regionkey",
+             "type" : "bigint"
+          }, {
+             "symbol" : "count",
+             "type" : "bigint"
+          } ],
+          "details" : [ "_col1 := count" ],
+          "estimates" : [ {
+             "outputRowCount" : "NaN",
+             "outputSizeInBytes" : "NaN",
+             "cpuCost" : "NaN",
+             "memoryCost" : "NaN",
+             "networkCost" : "NaN"
+          } ],
+          "children" : [ {
+             "id" : "145",
+             "name" : "RemoteSource",
+             "descriptor" : {
+                "sourceFragmentIds" : "[1]"
+             },
+             "outputs" : [ {
+                "symbol" : "regionkey",
+                "type" : "bigint"
+             }, {
+                "symbol" : "count",
+                "type" : "bigint"
+             } ],
+             "details" : [ ],
+             "estimates" : [ ],
+             "children" : [ ]
+          } ]
+       },
+       "1" : {
+          "id" : "4",
+          "name" : "Aggregate",
+          "descriptor" : {
+             "type" : "FINAL",
+             "keys" : "[regionkey]",
+             "hash" : "[]"
+          },
+          "outputs" : [ {
+             "symbol" : "regionkey",
+             "type" : "bigint"
+          }, {
+             "symbol" : "count",
+             "type" : "bigint"
+          } ],
+          "details" : [ "count := count(\"count_0\")" ],
+          "estimates" : [ {
+             "outputRowCount" : "NaN",
+             "outputSizeInBytes" : "NaN",
+             "cpuCost" : "NaN",
+             "memoryCost" : "NaN",
+             "networkCost" : "NaN"
+          } ],
+          "children" : [ {
+             "id" : "194",
+             "name" : "LocalExchange",
+             "descriptor" : {
+                "partitioning" : "SINGLE",
+                "isReplicateNullsAndAny" : "",
+                "hashColumn" : "[]",
+                "arguments" : "[]"
+             },
+             "outputs" : [ {
+                "symbol" : "regionkey",
+                "type" : "bigint"
+             }, {
+                "symbol" : "count_0",
+                "type" : "bigint"
+             } ],
+             "details" : [ ],
+             "estimates" : [ {
+                "outputRowCount" : "NaN",
+                "outputSizeInBytes" : "NaN",
+                "cpuCost" : "NaN",
+                "memoryCost" : "NaN",
+                "networkCost" : "NaN"
+             } ],
+             "children" : [ {
+                "id" : "227",
+                "name" : "Project",
+                "descriptor" : { },
+                "outputs" : [ {
+                   "symbol" : "regionkey",
+                   "type" : "bigint"
+                }, {
+                   "symbol" : "count_0",
+                   "type" : "bigint"
+                } ],
+                "details" : [ ],
+                "estimates" : [ {
+                   "outputRowCount" : "NaN",
+                   "outputSizeInBytes" : "NaN",
+                   "cpuCost" : "NaN",
+                   "memoryCost" : "NaN",
+                   "networkCost" : "NaN"
+                } ],
+                "children" : [ {
+                   "id" : "200",
+                   "name" : "RemoteSource",
+                   "descriptor" : {
+                      "sourceFragmentIds" : "[2]"
+                   },
+                   "outputs" : [ {
+                      "symbol" : "regionkey",
+                      "type" : "bigint"
+                   }, {
+                      "symbol" : "count_0",
+                      "type" : "bigint"
+                   }, {
+                      "symbol" : "$hashvalue",
+                      "type" : "bigint"
+                   } ],
+                   "details" : [ ],
+                   "estimates" : [ ],
+                   "children" : [ ]
+                } ]
+             } ]
+          } ]
+       },
+       "2" : {
+          "id" : "226",
+          "name" : "Project",
+          "descriptor" : { },
+          "outputs" : [ {
+             "symbol" : "regionkey",
+             "type" : "bigint"
+          }, {
+             "symbol" : "count_0",
+             "type" : "bigint"
+          }, {
+             "symbol" : "$hashvalue_1",
+             "type" : "bigint"
+          } ],
+          "details" : [ "$hashvalue_1 := combine_hash(bigint '0', COALESCE(\"$operator$hash_code\"(\"regionkey\"), 0))" ],
+          "estimates" : [ {
+             "outputRowCount" : "NaN",
+             "outputSizeInBytes" : "NaN",
+             "cpuCost" : "NaN",
+             "memoryCost" : "NaN",
+             "networkCost" : "NaN"
+          } ],
+          "children" : [ {
+             "id" : "198",
+             "name" : "Aggregate",
+             "descriptor" : {
+                "type" : "PARTIAL",
+                "keys" : "[regionkey]",
+                "hash" : "[]"
+             },
+             "outputs" : [ {
+                "symbol" : "regionkey",
+                "type" : "bigint"
+             }, {
+                "symbol" : "count_0",
+                "type" : "bigint"
+             } ],
+             "details" : [ "count_0 := count(*)" ],
+             "estimates" : [ ],
+             "children" : [ {
+                "id" : "0",
+                "name" : "TableScan",
+                "descriptor" : {
+                   "table" : "tpch:tiny:nation"
+                },
+                "outputs" : [ {
+                   "symbol" : "regionkey",
+                   "type" : "bigint"
+                } ],
+                "details" : [ "regionkey := tpch:regionkey" ],
+                "estimates" : [ {
+                   "outputRowCount" : 25.0,
+                   "outputSizeInBytes" : 225.0,
+                   "cpuCost" : 225.0,
+                   "memoryCost" : 0.0,
+                   "networkCost" : 0.0
+                } ],
+                "children" : [ ]
+             } ]
+          } ]
+       }
+    }
+
 EXPLAIN (TYPE VALIDATE)
 ^^^^^^^^^^^^^^^^^^^^^^^