perf: skip null check for parent and root fields

Yogu · Yogu · commit b5d77450b988 · 2025-11-04T17:15:55.000+01:00
The null checks prevent arangodb from applying the reduce-extraction-to-projection optimization.
diff --git a/spec/regression/root-fields/tests/root-and-parent-with-collect/aql/q.aql b/spec/regression/root-fields/tests/root-and-parent-with-collect/aql/q.aql
@@ -16,19 +16,19 @@ RETURN {
             IN v_root1.`children`[*].`children`[*][**]
             RETURN {
               "parent": { __cruddl_runtime_error_code: @var1, __cruddl_runtime_error: @var2 },
-              "root": (IS_NULL(v_root1) ? null : {
+              "root": {
                 "name": v_root1.`name`
-              })
+              }
             }
           ),
           "extensionGrandchildren": (
             FOR v_extensionGrandchild1
             IN v_root1.`children`[*].`extension`.`children`[*][**]
             RETURN {
               "parent": { __cruddl_runtime_error_code: @var3, __cruddl_runtime_error: @var4 },
-              "root": (IS_NULL(v_root1) ? null : {
+              "root": {
                 "name": v_root1.`name`
-              })
+              }
             }
           )
         }
@@ -44,13 +44,12 @@ RETURN {
           )
         )[**]
         SORT (v_grandchild2.`obj`.`name`)
-        LET v_root2 = v_grandchild2.`root`
         RETURN {
           "name": v_grandchild2.`obj`.`name`,
           "parent": { __cruddl_runtime_error_code: @var7, __cruddl_runtime_error: @var8 },
-          "root": (IS_NULL(v_root2) ? null : {
-            "name": v_root2.`name`
-          })
+          "root": {
+            "name": v_grandchild2.`root`.`name`
+          }
         }
       ),
       "rootExtensionGrandchildren": (
@@ -64,13 +63,12 @@ RETURN {
           )
         )[**]
         SORT (v_extensionGrandchild2.`obj`.`name`)
-        LET v_root3 = v_extensionGrandchild2.`root`
         RETURN {
           "name": v_extensionGrandchild2.`obj`.`name`,
           "parent": { __cruddl_runtime_error_code: @var11, __cruddl_runtime_error: @var12 },
-          "root": (IS_NULL(v_root3) ? null : {
-            "name": v_root3.`name`
-          })
+          "root": {
+            "name": v_extensionGrandchild2.`root`.`name`
+          }
         }
       )
     }
diff --git a/spec/regression/root-fields/tests/root-and-parent-with-intra-root-entity-collect/aql/test.aql b/spec/regression/root-fields/tests/root-and-parent-with-intra-root-entity-collect/aql/test.aql
@@ -11,9 +11,9 @@ RETURN {
         RETURN {
           "name": v_grandchild1.`name`,
           "parent": { __cruddl_runtime_error_code: @var1, __cruddl_runtime_error: @var2 },
-          "root": (IS_NULL(v_root1) ? null : {
+          "root": {
             "name": v_root1.`name`
-          })
+          }
         }
       ),
       "extensionGrandchildren": (
@@ -22,9 +22,9 @@ RETURN {
         RETURN {
           "name": v_extensionGrandchild1.`name`,
           "parent": { __cruddl_runtime_error_code: @var3, __cruddl_runtime_error: @var4 },
-          "root": (IS_NULL(v_root1) ? null : {
+          "root": {
             "name": v_root1.`name`
-          })
+          }
         }
       )
     }
diff --git a/spec/regression/root-fields/tests/root-and-parent/aql/test.aql b/spec/regression/root-fields/tests/root-and-parent/aql/test.aql
@@ -15,36 +15,36 @@ RETURN {
             IN (IS_LIST(v_child1.`children`) ? v_child1.`children` : [])
             RETURN {
               "name": v_grandchild1.`name`,
-              "parent": (IS_NULL(v_child1) ? null : {
+              "parent": {
                 "name": v_child1.`name`,
-                "parent": (IS_NULL(v_root1) ? null : {
+                "parent": {
                   "name": v_root1.`name`
-                }),
+                },
                 "children": (
                   FOR v_grandchild2
                   IN (IS_LIST(v_child1.`children`) ? v_child1.`children` : [])
                   RETURN {
                     "name": v_grandchild2.`name`,
-                    "parent": (IS_NULL(v_child1) ? null : {
+                    "parent": {
                       "name": v_child1.`name`,
-                      "parent": (IS_NULL(v_root1) ? null : {
+                      "parent": {
                         "name": v_root1.`name`
-                      })
-                    })
+                      }
+                    }
                   }
                 )
-              }),
-              "root": (IS_NULL(v_root1) ? null : {
+              },
+              "root": {
                 "name": v_root1.`name`
-              })
+              }
             }
           ),
-          "parent": (IS_NULL(v_root1) ? null : {
+          "parent": {
             "name": v_root1.`name`
-          }),
-          "root": (IS_NULL(v_root1) ? null : {
+          },
+          "root": {
             "name": v_root1.`name`
-          })
+          }
         }
       )
     }
diff --git a/spec/regression/root-fields/tests/root-with-collect/aql/filter.aql b/spec/regression/root-fields/tests/root-with-collect/aql/filter.aql
@@ -17,9 +17,9 @@ RETURN {
             FILTER (RIGHT(v_grandchild1.`name`, LENGTH(@var1)) == @var2)
             RETURN {
               "name": v_grandchild1.`name`,
-              "root": (IS_NULL(v_root1) ? null : {
+              "root": {
                 "name": v_root1.`name`
-              })
+              }
             }
           ),
           @var3: {
@@ -40,9 +40,9 @@ RETURN {
             IN v_root1.`children`[*].`extension`.`children`[*][**]
             FILTER (RIGHT(v_extensionGrandchild1.`name`, LENGTH(@var6)) == @var7)
             RETURN {
-              "root": (IS_NULL(v_root1) ? null : {
+              "root": {
                 "name": v_root1.`name`
-              })
+              }
             }
           ),
           @var8: {
@@ -72,12 +72,11 @@ RETURN {
         )[**]
         FILTER (RIGHT(v_grandchild3.`obj`.`name`, LENGTH(@var13)) == @var14)
         SORT (v_grandchild3.`obj`.`name`)
-        LET v_root2 = v_grandchild3.`root`
         RETURN {
           "name": v_grandchild3.`obj`.`name`,
-          "root": (IS_NULL(v_root2) ? null : {
-            "name": v_root2.`name`
-          })
+          "root": {
+            "name": v_grandchild3.`root`.`name`
+          }
         }
       ),
       @var15: {
@@ -109,12 +108,11 @@ RETURN {
         )[**]
         FILTER (RIGHT(v_extensionGrandchild3.`obj`.`name`, LENGTH(@var22)) == @var23)
         SORT (v_extensionGrandchild3.`obj`.`name`)
-        LET v_root3 = v_extensionGrandchild3.`root`
         RETURN {
           "name": v_extensionGrandchild3.`obj`.`name`,
-          "root": (IS_NULL(v_root3) ? null : {
-            "name": v_root3.`name`
-          })
+          "root": {
+            "name": v_extensionGrandchild3.`root`.`name`
+          }
         }
       ),
       @var24: {
diff --git a/spec/regression/root-fields/tests/root-with-collect/aql/order.aql b/spec/regression/root-fields/tests/root-with-collect/aql/order.aql
@@ -17,9 +17,9 @@ RETURN {
             SORT (v_grandchild1.`name`)
             RETURN {
               "name": v_grandchild1.`name`,
-              "root": (IS_NULL(v_root1) ? null : {
+              "root": {
                 "name": v_root1.`name`
-              })
+              }
             }
           ),
           "grandchildrenReverse": (
@@ -28,9 +28,9 @@ RETURN {
             SORT (v_grandchild2.`name`)  DESC
             RETURN {
               "name": v_grandchild2.`name`,
-              "root": (IS_NULL(v_root1) ? null : {
+              "root": {
                 "name": v_root1.`name`
-              })
+              }
             }
           ),
           "extensionGrandchildren": (
@@ -39,9 +39,9 @@ RETURN {
             SORT (v_extensionGrandchild1.`name`)
             RETURN {
               "name": v_extensionGrandchild1.`name`,
-              "root": (IS_NULL(v_root1) ? null : {
+              "root": {
                 "name": v_root1.`name`
-              })
+              }
             }
           ),
           "extensionGrandchildrenReverse": (
@@ -50,9 +50,9 @@ RETURN {
             SORT (v_extensionGrandchild2.`name`)  DESC
             RETURN {
               "name": v_extensionGrandchild2.`name`,
-              "root": (IS_NULL(v_root1) ? null : {
+              "root": {
                 "name": v_root1.`name`
-              })
+              }
             }
           )
         }
@@ -68,12 +68,11 @@ RETURN {
           )
         )[**]
         SORT (v_grandchild3.`obj`.`name`)
-        LET v_root2 = v_grandchild3.`root`
         RETURN {
           "name": v_grandchild3.`obj`.`name`,
-          "root": (IS_NULL(v_root2) ? null : {
-            "name": v_root2.`name`
-          })
+          "root": {
+            "name": v_grandchild3.`root`.`name`
+          }
         }
       ),
       "rootGrandchildrenReverse": (
@@ -87,12 +86,11 @@ RETURN {
           )
         )[**]
         SORT (v_grandchild4.`obj`.`name`)  DESC
-        LET v_root3 = v_grandchild4.`root`
         RETURN {
           "name": v_grandchild4.`obj`.`name`,
-          "root": (IS_NULL(v_root3) ? null : {
-            "name": v_root3.`name`
-          })
+          "root": {
+            "name": v_grandchild4.`root`.`name`
+          }
         }
       ),
       "rootExtensionGrandchildren": (
@@ -106,12 +104,11 @@ RETURN {
           )
         )[**]
         SORT (v_extensionGrandchild3.`obj`.`name`)
-        LET v_root4 = v_extensionGrandchild3.`root`
         RETURN {
           "name": v_extensionGrandchild3.`obj`.`name`,
-          "root": (IS_NULL(v_root4) ? null : {
-            "name": v_root4.`name`
-          })
+          "root": {
+            "name": v_extensionGrandchild3.`root`.`name`
+          }
         }
       ),
       "rootExtensionGrandchildrenReverse": (
@@ -125,12 +122,11 @@ RETURN {
           )
         )[**]
         SORT (v_extensionGrandchild4.`obj`.`name`)  DESC
-        LET v_root5 = v_extensionGrandchild4.`root`
         RETURN {
           "name": v_extensionGrandchild4.`obj`.`name`,
-          "root": (IS_NULL(v_root5) ? null : {
-            "name": v_root5.`name`
-          })
+          "root": {
+            "name": v_extensionGrandchild4.`root`.`name`
+          }
         }
       )
     }
diff --git a/spec/regression/root-fields/tests/root-with-collect/aql/q.aql b/spec/regression/root-fields/tests/root-with-collect/aql/q.aql
@@ -15,18 +15,18 @@ RETURN {
             FOR v_grandchild1
             IN v_root1.`children`[*].`children`[*][**]
             RETURN {
-              "root": (IS_NULL(v_root1) ? null : {
+              "root": {
                 "name": v_root1.`name`
-              })
+              }
             }
           ),
           "extensionGrandchildren": (
             FOR v_extensionGrandchild1
             IN v_root1.`children`[*].`extension`.`children`[*][**]
             RETURN {
-              "root": (IS_NULL(v_root1) ? null : {
+              "root": {
                 "name": v_root1.`name`
-              })
+              }
             }
           )
         }
@@ -42,12 +42,11 @@ RETURN {
           )
         )[**]
         SORT (v_grandchild2.`obj`.`name`)
-        LET v_root2 = v_grandchild2.`root`
         RETURN {
           "name": v_grandchild2.`obj`.`name`,
-          "root": (IS_NULL(v_root2) ? null : {
-            "name": v_root2.`name`
-          })
+          "root": {
+            "name": v_grandchild2.`root`.`name`
+          }
         }
       ),
       "rootExtensionGrandchildren": (
@@ -61,12 +60,11 @@ RETURN {
           )
         )[**]
         SORT (v_extensionGrandchild2.`obj`.`name`)
-        LET v_root3 = v_extensionGrandchild2.`root`
         RETURN {
           "name": v_extensionGrandchild2.`obj`.`name`,
-          "root": (IS_NULL(v_root3) ? null : {
-            "name": v_root3.`name`
-          })
+          "root": {
+            "name": v_extensionGrandchild2.`root`.`name`
+          }
         }
       )
     }
diff --git a/spec/regression/traversal-performance/tests/collect/aql/RelationAndFieldTraversalWithParent.aql b/spec/regression/traversal-performance/tests/collect/aql/RelationAndFieldTraversalWithParent.aql
@@ -18,12 +18,11 @@ RETURN {
           RETURN { obj: v_entity1, root: v_node1 }
         )
       )[**]
-      LET v_root1 = v_child1.`root`
       RETURN {
         "key": v_child1.`obj`.`key`,
-        "parent": (IS_NULL(v_root1) ? null : {
-          "key": v_root1.`key`
-        })
+        "parent": {
+          "key": v_child1.`root`.`key`
+        }
       }
     )
   })
diff --git a/spec/regression/traversal-performance/tests/collect/result.json b/spec/regression/traversal-performance/tests/collect/result.json
@@ -19,7 +19,7 @@
   "RelationAndFieldTraversalWithParent": {
     "errors": [
       {
-        "message": "AQL: query would use more memory than allowed [node #17: TraversalNode] [node #18: CalculationNode] [node #19: FilterNode] [node #43: SubqueryStartNode] [node #22: FilterNode] [node #23: CalculationNode] [node #24: EnumerateListNode] [node #25: CalculationNode] [node #44: SubqueryEndNode] [node #42: SubqueryEndNode] [node #39: SubqueryStartNode] [node #13: FilterNode] [node #30: CalculationNode] [node #31: EnumerateListNode] [node #33: CalculationNode] [node #40: SubqueryEndNode] [node #36: CalculationNode] [node #37: ReturnNode] (while executing)",
+        "message": "AQL: query would use more memory than allowed [node #17: TraversalNode] [node #18: CalculationNode] [node #19: FilterNode] [node #42: SubqueryStartNode] [node #22: FilterNode] [node #23: CalculationNode] [node #24: EnumerateListNode] [node #25: CalculationNode] [node #43: SubqueryEndNode] [node #41: SubqueryEndNode] [node #38: SubqueryStartNode] [node #13: FilterNode] [node #30: CalculationNode] [node #31: EnumerateListNode] [node #32: CalculationNode] [node #39: SubqueryEndNode] [node #35: CalculationNode] [node #36: ReturnNode] (while executing)",
         "locations": [
           {
             "line": 10,
diff --git a/src/schema-generation/output-type-generator.ts b/src/schema-generation/output-type-generator.ts
@@ -227,7 +227,10 @@ export class OutputTypeGenerator {
             // a check that they return null if the source node is null.
             // if we skip both, entity extensions will be passed as null, but they will only ever be used to look up
             // fields in them, and a FieldQueryNode returns null if the source is null.
-            skipNullCheck: field.type.isEntityExtensionType,
+            // parent fields and root fields can never be null (either they exist, or querying them throws an error)
+            // it's important to skip the null check because ArangoDB would otherwise no longer use the reduce-extraction-to-projection  optimiztion
+            skipNullCheck:
+                field.type.isEntityExtensionType || field.isParentField || field.isRootField,
             isPure: true,
             resolve: (sourceNode, args, info) => this.resolveField(field, sourceNode, info),
         };
diff --git a/src/schema-generation/query-node-object-type/query-node-generator.ts b/src/schema-generation/query-node-object-type/query-node-generator.ts

Original file line number	Diff line number	Diff line change
`@@ -11,9 +11,9 @@ RETURN {`
`11`	`11`	`RETURN {`
`12`	`12`	"name": v_grandchild1.`name`,
`13`	`13`	`"parent": { __cruddl_runtime_error_code: @var1, __cruddl_runtime_error: @var2 },`
`14`		`- "root": (IS_NULL(v_root1) ? null : {`
	`14`	`+ "root": {`
`15`	`15`	"name": v_root1.`name`
`16`		`- })`
	`16`	`+ }`
`17`	`17`	`}`
`18`	`18`	`),`
`19`	`19`	`"extensionGrandchildren": (`
`@@ -22,9 +22,9 @@ RETURN {`
`22`	`22`	`RETURN {`
`23`	`23`	"name": v_extensionGrandchild1.`name`,
`24`	`24`	`"parent": { __cruddl_runtime_error_code: @var3, __cruddl_runtime_error: @var4 },`
`25`		`- "root": (IS_NULL(v_root1) ? null : {`
	`25`	`+ "root": {`
`26`	`26`	"name": v_root1.`name`
`27`		`- })`
	`27`	`+ }`
`28`	`28`	`}`
`29`	`29`	`)`
`30`	`30`	`}`
Original file line number	Diff line number	Diff line change
`@@ -15,18 +15,18 @@ RETURN {`
`15`	`15`	`FOR v_grandchild1`
`16`	`16`	IN v_root1.`children`[].`children`[][**]
`17`	`17`	`RETURN {`
`18`		`- "root": (IS_NULL(v_root1) ? null : {`
	`18`	`+ "root": {`
`19`	`19`	"name": v_root1.`name`
`20`		`- })`
	`20`	`+ }`
`21`	`21`	`}`
`22`	`22`	`),`
`23`	`23`	`"extensionGrandchildren": (`
`24`	`24`	`FOR v_extensionGrandchild1`
`25`	`25`	IN v_root1.`children`[].`extension`.`children`[][**]
`26`	`26`	`RETURN {`
`27`		`- "root": (IS_NULL(v_root1) ? null : {`
	`27`	`+ "root": {`
`28`	`28`	"name": v_root1.`name`
`29`		`- })`
	`29`	`+ }`
`30`	`30`	`}`
`31`	`31`	`)`
`32`	`32`	`}`
`@@ -42,12 +42,11 @@ RETURN {`
`42`	`42`	`)`
`43`	`43`	`)[**]`
`44`	`44`	SORT (v_grandchild2.`obj`.`name`)
`45`		- LET v_root2 = v_grandchild2.`root`
`46`	`45`	`RETURN {`
`47`	`46`	"name": v_grandchild2.`obj`.`name`,
`48`		`- "root": (IS_NULL(v_root2) ? null : {`
`49`		- "name": v_root2.`name`
`50`		`- })`
	`47`	`+ "root": {`
	`48`	+ "name": v_grandchild2.`root`.`name`
	`49`	`+ }`
`51`	`50`	`}`
`52`	`51`	`),`
`53`	`52`	`"rootExtensionGrandchildren": (`
`@@ -61,12 +60,11 @@ RETURN {`
`61`	`60`	`)`
`62`	`61`	`)[**]`
`63`	`62`	SORT (v_extensionGrandchild2.`obj`.`name`)
`64`		- LET v_root3 = v_extensionGrandchild2.`root`
`65`	`63`	`RETURN {`
`66`	`64`	"name": v_extensionGrandchild2.`obj`.`name`,
`67`		`- "root": (IS_NULL(v_root3) ? null : {`
`68`		- "name": v_root3.`name`
`69`		`- })`
	`65`	`+ "root": {`
	`66`	+ "name": v_extensionGrandchild2.`root`.`name`
	`67`	`+ }`
`70`	`68`	`}`
`71`	`69`	`)`
`72`	`70`	`}`
Original file line number	Diff line number	Diff line change
`@@ -18,12 +18,11 @@ RETURN {`
`18`	`18`	`RETURN { obj: v_entity1, root: v_node1 }`
`19`	`19`	`)`
`20`	`20`	`)[**]`
`21`		- LET v_root1 = v_child1.`root`
`22`	`21`	`RETURN {`
`23`	`22`	"key": v_child1.`obj`.`key`,
`24`		`- "parent": (IS_NULL(v_root1) ? null : {`
`25`		- "key": v_root1.`key`
`26`		`- })`
	`23`	`+ "parent": {`
	`24`	+ "key": v_child1.`root`.`key`
	`25`	`+ }`
`27`	`26`	`}`
`28`	`27`	`)`
`29`	`28`	`})`
Original file line number	Diff line number	Diff line change
`@@ -19,7 +19,7 @@`
`19`	`19`	`"RelationAndFieldTraversalWithParent": {`
`20`	`20`	`"errors": [`
`21`	`21`	`{`
`22`		- "message": "AQL: query would use more memory than allowed [node #17: TraversalNode] [node #18: CalculationNode] [node #19: FilterNode] [node #43: SubqueryStartNode] [node #22: FilterNode] [node #23: CalculationNode] [node #24: EnumerateListNode] [node #25: CalculationNode] [node #44: SubqueryEndNode] [node #42: SubqueryEndNode] [node #39: SubqueryStartNode] [node #13: FilterNode] [node #30: CalculationNode] [node #31: EnumerateListNode] [node #33: CalculationNode] [node #40: SubqueryEndNode] [node #36: CalculationNode] [node #37: ReturnNode] (while executing)",
	`22`	+ "message": "AQL: query would use more memory than allowed [node #17: TraversalNode] [node #18: CalculationNode] [node #19: FilterNode] [node #42: SubqueryStartNode] [node #22: FilterNode] [node #23: CalculationNode] [node #24: EnumerateListNode] [node #25: CalculationNode] [node #43: SubqueryEndNode] [node #41: SubqueryEndNode] [node #38: SubqueryStartNode] [node #13: FilterNode] [node #30: CalculationNode] [node #31: EnumerateListNode] [node #32: CalculationNode] [node #39: SubqueryEndNode] [node #35: CalculationNode] [node #36: ReturnNode] (while executing)",
`23`	`23`	`"locations": [`
`24`	`24`	`{`
`25`	`25`	`"line": 10,`