diff --git a/server/graphql-engine.cabal b/server/graphql-engine.cabal
index 7ec054d1aa7..1abf4b7613b 100644
--- a/server/graphql-engine.cabal
+++ b/server/graphql-engine.cabal
@@ -1227,7 +1227,6 @@ test-suite tests-hspec
 
  -- Test
     Test.ArrayParamPermissionSpec
-    Test.ArrayRelationshipsSpec
     Test.BackendOnlyPermissionsSpec
     Test.BasicFieldsSpec
     Test.BigQuery.ComputedFieldSpec
@@ -1264,7 +1263,6 @@ test-suite tests-hspec
     Test.LongIdentifiersSpec
     Test.NestedRelationshipsSpec
     Test.ObjectRelationshipsLimitSpec
-    Test.ObjectRelationshipsSpec
     Test.Queries.FilterSearchSpec
     Test.OrderingSpec
     Test.PostgresTypesSpec
@@ -1280,6 +1278,8 @@ test-suite tests-hspec
     Test.RemoteRelationship.XToRemoteSchemaRelationshipSpec
     Test.RequestHeadersSpec
     Test.RunSQLSpec
+    Test.Schema.TableRelationships.ArrayRelationshipsSpec
+    Test.Schema.TableRelationships.ObjectRelationshipsSpec
     Test.Schema.DataValidation.PermissionSpec
     Test.SQLServer.InsertVarcharColumnSpec
     Test.SelectSpec
diff --git a/server/tests-hspec/Harness/Test/BackendType.hs b/server/tests-hspec/Harness/Test/BackendType.hs
index ca740d857ad..6de59b468d3 100644
--- a/server/tests-hspec/Harness/Test/BackendType.hs
+++ b/server/tests-hspec/Harness/Test/BackendType.hs
@@ -20,7 +20,7 @@ data BackendType
   | BigQuery
   | Citus
   | DataConnector
-  deriving (Show)
+  deriving (Eq, Show)
 
 -- | The default hasura metadata source name used for a given backend in this test suite project.
 defaultSource :: BackendType -> String
diff --git a/server/tests-hspec/Test/ArrayRelationshipsSpec.hs b/server/tests-hspec/Test/ArrayRelationshipsSpec.hs
deleted file mode 100644
index e0e9e872a19..00000000000
--- a/server/tests-hspec/Test/ArrayRelationshipsSpec.hs
+++ /dev/null
@@ -1,128 +0,0 @@
-{-# LANGUAGE QuasiQuotes #-}
-
--- | Testing array relationships.
-module Test.ArrayRelationshipsSpec (spec) where
-
-import Harness.Backend.Mysql as Mysql
-import Harness.GraphqlEngine qualified as GraphqlEngine
-import Harness.Quoter.Graphql
-import Harness.Quoter.Yaml
-import Harness.Test.Context qualified as Context
-import Harness.Test.Schema (Table (..), table)
-import Harness.Test.Schema qualified as Schema
-import Harness.TestEnvironment (TestEnvironment)
-import Test.Hspec
-import Prelude
-
---------------------------------------------------------------------------------
--- Preamble
-
-spec :: SpecWith TestEnvironment
-spec =
-  Context.run
-    [ Context.Context
-        { name = Context.Backend Context.MySQL,
-          mkLocalTestEnvironment = Context.noLocalTestEnvironment,
-          setup = Mysql.setup schema,
-          teardown = Mysql.teardown schema,
-          customOptions = Nothing
-        }
-    ]
-    tests
-
---------------------------------------------------------------------------------
--- Schema
-
-schema :: [Schema.Table]
-schema = [author, article]
-
-author :: Schema.Table
-author =
-  (table "author")
-    { tableColumns =
-        [ Schema.column "id" Schema.TInt,
-          Schema.column "name" Schema.TStr,
-          Schema.column "createdAt" Schema.TUTCTime
-        ],
-      tablePrimaryKey = ["id"],
-      tableData =
-        [ [Schema.VInt 1, Schema.VStr "Author 1", Schema.parseUTCTimeOrError "2017-09-21 09:39:44"],
-          [Schema.VInt 2, Schema.VStr "Author 2", Schema.parseUTCTimeOrError "2017-09-21 09:50:44"]
-        ]
-    }
-
-article :: Schema.Table
-article =
-  (table "article")
-    { tableColumns =
-        [ Schema.column "id" Schema.TInt,
-          Schema.column "title" Schema.TStr,
-          Schema.column "content" Schema.TStr,
-          Schema.column "is_published" Schema.TBool,
-          Schema.column "published_on" Schema.TUTCTime,
-          Schema.columnNull "author_id" Schema.TInt,
-          Schema.columnNull "co_author_id" Schema.TInt
-        ],
-      tablePrimaryKey = ["id"],
-      tableReferences =
-        [ Schema.Reference "author_id" "author" "id",
-          Schema.Reference "co_author_id" "author" "id"
-        ],
-      tableData =
-        [ [ Schema.VInt 1,
-            Schema.VStr "Article 1",
-            Schema.VStr "Sample article content 1",
-            Schema.VBool False,
-            Schema.parseUTCTimeOrError "2022-01-01 00:00:00",
-            Schema.VInt 1,
-            Schema.VInt 2
-          ],
-          [ Schema.VInt 2,
-            Schema.VStr "Article 2",
-            Schema.VStr "Sample article content 2",
-            Schema.VBool True,
-            Schema.parseUTCTimeOrError "2022-01-01 00:00:00",
-            Schema.VInt 1,
-            Schema.VInt 2
-          ],
-          [ Schema.VInt 3,
-            Schema.VStr "Article 3",
-            Schema.VStr "Sample article content 3",
-            Schema.VBool True,
-            Schema.parseUTCTimeOrError "2022-01-01 00:00:00",
-            Schema.VInt 2,
-            Schema.VInt 1
-          ]
-        ]
-    }
-
---------------------------------------------------------------------------------
--- Tests
-
-tests :: Context.Options -> SpecWith TestEnvironment
-tests opts = do
-  it "Select an author and one of their articles" $ \testEnvironment ->
-    shouldReturnYaml
-      opts
-      ( GraphqlEngine.postGraphql
-          testEnvironment
-          [graphql|
-query {
-  # we put id=1 restrictions here because we don't assume ordering support
-  hasura_author(where: {id: {_eq: 1}}) {
-    id
-    # the _by_id_to_author_id part is necessary to distinguish between multiple foreign key relationships between the same two tables
-    articles_by_id_to_author_id(where: {id: {_eq: 1}}) {
-      id
-    }
-  }
-}
-|]
-      )
-      [yaml|
-data:
-  hasura_author:
-  - id: 1
-    articles_by_id_to_author_id:
-      - id: 1
-|]
diff --git a/server/tests-hspec/Test/ObjectRelationshipsSpec.hs b/server/tests-hspec/Test/ObjectRelationshipsSpec.hs
deleted file mode 100644
index cb72f2769af..00000000000
--- a/server/tests-hspec/Test/ObjectRelationshipsSpec.hs
+++ /dev/null
@@ -1,155 +0,0 @@
-{-# LANGUAGE QuasiQuotes #-}
-
--- | Testing object relationships.
-module Test.ObjectRelationshipsSpec (spec) where
-
-import Harness.Backend.Mysql qualified as Mysql
-import Harness.Backend.Sqlserver qualified as Sqlserver
-import Harness.GraphqlEngine qualified as GraphqlEngine
-import Harness.Quoter.Graphql
-import Harness.Quoter.Yaml
-import Harness.Test.Context qualified as Context
-import Harness.Test.Schema (Table (..), table)
-import Harness.Test.Schema qualified as Schema
-import Harness.TestEnvironment (TestEnvironment)
-import Test.Hspec
-import Prelude
-
---------------------------------------------------------------------------------
--- Preamble
-
-spec :: SpecWith TestEnvironment
-spec = do
-  Context.run
-    [ Context.Context
-        { name = Context.Backend Context.SQLServer,
-          mkLocalTestEnvironment = Context.noLocalTestEnvironment,
-          setup = Sqlserver.setup schema,
-          teardown = Sqlserver.teardown schema,
-          customOptions = Nothing
-        }
-    ]
-    mssqlTests
-
-  Context.run
-    [ Context.Context
-        { name = Context.Backend Context.MySQL,
-          mkLocalTestEnvironment = Context.noLocalTestEnvironment,
-          setup = Mysql.setup schema,
-          teardown = Mysql.teardown schema,
-          customOptions = Nothing
-        }
-    ]
-    mysqlTests
-
---------------------------------------------------------------------------------
--- Schema
-
-schema :: [Schema.Table]
-schema = [author, article]
-
-author :: Schema.Table
-author =
-  (table "author")
-    { tableColumns =
-        [ Schema.column "id" Schema.TInt,
-          Schema.column "name" Schema.TStr
-        ],
-      tablePrimaryKey = ["id"],
-      tableData =
-        [ [Schema.VInt 1, Schema.VStr "Author 1"],
-          [Schema.VInt 2, Schema.VStr "Author 2"]
-        ]
-    }
-
-article :: Schema.Table
-article =
-  (table "article")
-    { tableColumns =
-        [ Schema.column "id" Schema.TInt,
-          Schema.columnNull "author_id" Schema.TInt
-        ],
-      tablePrimaryKey = ["id"],
-      tableReferences = [Schema.Reference "author_id" "author" "id"],
-      tableData =
-        [ [ Schema.VInt 1,
-            Schema.VInt 1
-          ],
-          [ Schema.VInt 2,
-            Schema.VInt 1
-          ],
-          [ Schema.VInt 3,
-            Schema.VInt 2
-          ],
-          [ Schema.VInt 4,
-            Schema.VNull
-          ]
-        ]
-    }
-
---------------------------------------------------------------------------------
--- Tests
-
-mssqlTests :: Context.Options -> SpecWith TestEnvironment
-mssqlTests opts = do
-  usingWhereClause opts
-  nullField opts
-
-mysqlTests :: Context.Options -> SpecWith TestEnvironment
-mysqlTests opts = do
-  usingWhereClause opts
-  xdescribe
-    "Pending: The MySQL backend currently fails with relationship fields that are null.\
-    \ (https://github.com/hasura/graphql-engine-mono/issues/3650)"
-    (nullField opts)
-
-usingWhereClause :: Context.Options -> SpecWith TestEnvironment
-usingWhereClause opts = do
-  it "Author of article where id=1" $ \testEnvironment ->
-    shouldReturnYaml
-      opts
-      ( GraphqlEngine.postGraphql
-          testEnvironment
-          [graphql|
-query {
-  hasura_article(where: {id: {_eq: 1}}) {
-    id
-    author_by_author_id_to_id {
-      id
-    }
-  }
-}
-|]
-      )
-      [yaml|
-data:
-  hasura_article:
-  - id: 1
-    author_by_author_id_to_id:
-      id: 1
-|]
-
-nullField :: Context.Options -> SpecWith TestEnvironment
-nullField opts = do
-  it "Can realise a null relationship field" $ \testEnvironment ->
-    shouldReturnYaml
-      opts
-      ( GraphqlEngine.postGraphql
-          testEnvironment
-          [graphql|
-query {
-  hasura_article(where: {id: {_eq: 4}}) {
-    id
-    author_by_author_id_to_id {
-      id
-    }
-  }
-}
-|]
-      )
-      [yaml|
-data:
-  hasura_article:
-  - author_by_author_id_to_id: null
-    id: 4
-|]
diff --git a/server/tests-hspec/Test/Schema/TableRelationships/ArrayRelationshipsSpec.hs b/server/tests-hspec/Test/Schema/TableRelationships/ArrayRelationshipsSpec.hs
new file mode 100644
index 00000000000..bf01092961d
--- /dev/null
+++ b/server/tests-hspec/Test/Schema/TableRelationships/ArrayRelationshipsSpec.hs
@@ -0,0 +1,152 @@
+{-# LANGUAGE QuasiQuotes #-}
+
+module Test.Schema.TableRelationships.ArrayRelationshipsSpec (spec) where
+
+import Data.Aeson (Value)
+import Harness.Backend.BigQuery qualified as BigQuery
+import Harness.Backend.Citus qualified as Citus
+import Harness.Backend.Mysql qualified as Mysql
+import Harness.Backend.Postgres qualified as Postgres
+import Harness.Backend.Sqlserver qualified as Sqlserver
+import Harness.GraphqlEngine (postGraphql)
+import Harness.Quoter.Graphql (graphql)
+import Harness.Quoter.Yaml (shouldReturnYaml, yaml)
+import Harness.Test.Context qualified as Context
+import Harness.Test.Schema (Table (..), table)
+import Harness.Test.Schema qualified as Schema
+import Harness.TestEnvironment (TestEnvironment)
+import Test.Hspec (SpecWith, describe, it)
+import Prelude
+
+spec :: SpecWith TestEnvironment
+spec = do
+  Context.run
+    [ Context.Context
+        { name = Context.Backend Context.MySQL,
+          mkLocalTestEnvironment = Context.noLocalTestEnvironment,
+          setup = Mysql.setup schema,
+          teardown = Mysql.teardown schema,
+          customOptions = Nothing
+        },
+      Context.Context
+        { name = Context.Backend Context.Postgres,
+          mkLocalTestEnvironment = Context.noLocalTestEnvironment,
+          setup = Postgres.setup schema,
+          teardown = Postgres.teardown schema,
+          customOptions = Nothing
+        },
+      Context.Context
+        { name = Context.Backend Context.Citus,
+          mkLocalTestEnvironment = Context.noLocalTestEnvironment,
+          setup = Citus.setup schema,
+          teardown = Citus.teardown schema,
+          customOptions = Nothing
+        },
+      Context.Context
+        { name = Context.Backend Context.SQLServer,
+          mkLocalTestEnvironment = Context.noLocalTestEnvironment,
+          setup = Sqlserver.setup schema,
+          teardown = Sqlserver.teardown schema,
+          customOptions = Nothing
+        },
+      Context.Context
+        { name = Context.Backend Context.BigQuery,
+          mkLocalTestEnvironment = Context.noLocalTestEnvironment,
+          setup = BigQuery.setup schema,
+          teardown = BigQuery.teardown schema,
+          customOptions =
+            Just $
+              Context.Options
+                { stringifyNumbers = True
+                }
+        }
+    ]
+    tests
+
+--------------------------------------------------------------------------------
+-- Schema
+
+schema :: [Schema.Table]
+schema =
+  [ (table "author")
+      { tableColumns =
+          [ Schema.column "id" Schema.TInt,
+            Schema.column "name" Schema.TStr
+          ],
+        tablePrimaryKey = ["id"],
+        tableData =
+          [ [Schema.VInt 1, Schema.VStr "Author 1"],
+            [Schema.VInt 2, Schema.VStr "Author 2"]
+          ]
+      },
+    (table "article")
+      { tableColumns =
+          [ Schema.column "id" Schema.TInt,
+            Schema.column "title" Schema.TStr,
+            Schema.column "author_id" Schema.TInt
+          ],
+        tablePrimaryKey = ["id"],
+        tableReferences =
+          [ Schema.Reference "author_id" "author" "id"
+          ],
+        tableData =
+          [ [ Schema.VInt 1,
+              Schema.VStr "Article 1",
+              Schema.VInt 1
+            ],
+            [ Schema.VInt 2,
+              Schema.VStr "Article 2",
+              Schema.VInt 1
+            ],
+            [ Schema.VInt 3,
+              Schema.VStr "Article 3",
+              Schema.VInt 2
+            ]
+          ]
+      }
+  ]
+
+--------------------------------------------------------------------------------
+-- Tests
+
+tests :: Context.Options -> SpecWith TestEnvironment
+tests opts = do
+  let shouldBe :: IO Value -> Value -> IO ()
+      shouldBe = shouldReturnYaml opts
+
+  describe "Array relationships" do
+    it "Select authors and their articles" \testEnvironment -> do
+      let expected :: Value
+          expected =
+            [yaml|
+              data:
+                hasura_author:
+                - id: 1
+                  articles_by_id_to_author_id:
+                  - id: 1
+                  - id: 2
+
+                - id: 2
+                  articles_by_id_to_author_id:
+                  - id: 3
+            |]
+
+          -- We have to provide explicit orderings because BigQuery doesn't
+          -- seem to return results in a deterministic order.
+          actual :: IO Value
+          actual =
+            postGraphql
+              testEnvironment
+              [graphql|
+                query {
+                  hasura_author(order_by: [{ id: asc }]) {
+                    id
+
+                    articles_by_id_to_author_id(order_by: [{ id: asc }]) {
+                      id
+                    }
+                  }
+                }
+              |]
+
+      actual `shouldBe` expected
diff --git a/server/tests-hspec/Test/Schema/TableRelationships/ObjectRelationshipsSpec.hs b/server/tests-hspec/Test/Schema/TableRelationships/ObjectRelationshipsSpec.hs
new file mode 100644
index 00000000000..86593885399
--- /dev/null
+++ b/server/tests-hspec/Test/Schema/TableRelationships/ObjectRelationshipsSpec.hs
@@ -0,0 +1,218 @@
+{-# LANGUAGE QuasiQuotes #-}
+
+-- |
+-- Queries over object relationships between tables in the schema.
+--
+-- TODO: MySQL link when docs are released?
+-- https://hasura.io/docs/latest/schema/postgres/table-relationships/index
+-- https://hasura.io/docs/latest/schema/ms-sql-server/table-relationships/index
+-- https://hasura.io/docs/latest/schema/bigquery/table-relationships/index/
+module Test.Schema.TableRelationships.ObjectRelationshipsSpec (spec) where
+
+import Control.Monad (unless)
+import Data.Aeson (Value)
+import Harness.Backend.BigQuery qualified as BigQuery
+import Harness.Backend.Mysql qualified as Mysql
+import Harness.Backend.Postgres qualified as Postgres
+import Harness.GraphqlEngine (postGraphql)
+import Harness.Quoter.Graphql (graphql)
+import Harness.Quoter.Yaml (shouldReturnYaml, yaml)
+import Harness.Test.BackendType (BackendType (..))
+import Harness.Test.Context (Options (..))
+import Harness.Test.Context qualified as Context
+import Harness.Test.Schema (Table (..), table)
+import Harness.Test.Schema qualified as Schema
+import Harness.TestEnvironment (TestEnvironment)
+import Test.Hspec (SpecWith, describe, it)
+import Prelude
+
+spec :: SpecWith TestEnvironment
+spec = do
+  Context.run
+    [ Context.Context
+        { name = Context.Backend Context.MySQL,
+          mkLocalTestEnvironment = Context.noLocalTestEnvironment,
+          setup = Mysql.setup schema,
+          teardown = Mysql.teardown schema,
+          customOptions = Nothing
+        }
+    ]
+    $ tests MySQL
+
+  Context.run
+    [ Context.Context
+        { name = Context.Backend Context.Postgres,
+          mkLocalTestEnvironment = Context.noLocalTestEnvironment,
+          setup = Postgres.setup schema,
+          teardown = Postgres.teardown schema,
+          customOptions = Nothing
+        }
+    ]
+    $ tests Postgres
+
+  --   Context.run
+  --     [ Context.Context
+  --         { name = Context.Backend Context.Citus,
+  --           mkLocalTestEnvironment = Context.noLocalTestEnvironment,
+  --           setup = Citus.setup schema,
+  --           teardown = Citus.teardown schema,
+  --           customOptions = Nothing
+  --         }
+  --     ]
+  --     $ tests Citus
+
+  --   Context.run
+  --     [ Context.Context
+  --         { name = Context.Backend Context.SQLServer,
+  --           mkLocalTestEnvironment = Context.noLocalTestEnvironment,
+  --           setup = Sqlserver.setup schema,
+  --           teardown = Sqlserver.teardown schema,
+  --           customOptions = Nothing
+  --         }
+  --     ]
+  --     $ tests SQLServer
+
+  Context.run
+    [ Context.Context
+        { name = Context.Backend Context.BigQuery,
+          mkLocalTestEnvironment = Context.noLocalTestEnvironment,
+          setup = BigQuery.setup schema,
+          teardown = BigQuery.teardown schema,
+          customOptions =
+            Just $
+              Context.Options
+                { stringifyNumbers = True
+                }
+        }
+    ]
+    $ tests BigQuery
+
+--------------------------------------------------------------------------------
+-- Schema
+
+schema :: [Schema.Table]
+schema =
+  [ (table "author")
+      { tableColumns =
+          [ Schema.column "id" Schema.TInt,
+            Schema.column "name" Schema.TStr
+          ],
+        tablePrimaryKey = ["id"],
+        tableData =
+          [ [Schema.VInt 1, Schema.VStr "Author 1"],
+            [Schema.VInt 2, Schema.VStr "Author 2"]
+          ]
+      },
+    (table "article")
+      { tableColumns =
+          [ Schema.column "id" Schema.TInt,
+            Schema.column "title" Schema.TStr,
+            Schema.column "author_id" Schema.TInt,
+            Schema.columnNull "co_author_id" Schema.TInt
+          ],
+        tablePrimaryKey = ["id"],
+        tableReferences =
+          [ Schema.Reference "author_id" "author" "id",
+            Schema.Reference "co_author_id" "author" "id"
+          ],
+        tableData =
+          [ [ Schema.VInt 1,
+              Schema.VStr "Article 1",
+              Schema.VInt 1,
+              Schema.VNull
+            ],
+            [ Schema.VInt 2,
+              Schema.VStr "Article 2",
+              Schema.VInt 1,
+              Schema.VNull
+            ],
+            [ Schema.VInt 3,
+              Schema.VStr "Article 3",
+              Schema.VInt 2,
+              Schema.VInt 1
+            ]
+          ]
+      }
+  ]
+
+--------------------------------------------------------------------------------
+-- Tests
+
+tests :: BackendType -> Context.Options -> SpecWith TestEnvironment
+tests backend opts = describe "Object relationships" do
+  let shouldBe :: IO Value -> Value -> IO ()
+      shouldBe = shouldReturnYaml opts
+
+  it "Select articles and their authors" \testEnvironment -> do
+    let expected :: Value
+        expected =
+          [yaml|
+            data:
+              hasura_article:
+              - id: 1
+                author_by_author_id_to_id:
+                  id: 1
+
+              - id: 2
+                author_by_author_id_to_id:
+                  id: 1
+
+              - id: 3
+                author_by_author_id_to_id:
+                  id: 2
+          |]
+
+        -- We have to provide explicit orderings because BigQuery doesn't
+        -- seem to return results in a deterministic order.
+        actual :: IO Value
+        actual =
+          postGraphql
+            testEnvironment
+            [graphql|
+              query {
+                hasura_article(order_by: [{ id: asc }]) {
+                  id
+
+                  author_by_author_id_to_id {
+                    id
+                  }
+                }
+              }
+            |]
+
+    actual `shouldBe` expected
+
+  unless (backend `elem` [MySQL, BigQuery]) do
+    describe "Null relationships" do
+      it "Select articles their (possibly null) co-authors" \testEnvironment -> do
+        let expected :: Value
+            expected =
+              [yaml|
+                data:
+                  hasura_article:
+                  - id: 1
+                    author_by_co_author_id_to_id: null
+                  - id: 2
+                    author_by_co_author_id_to_id: null
+                  - id: 3
+                    author_by_co_author_id_to_id:
+                      id: 1
+              |]
+
+            actual :: IO Value
+            actual =
+              postGraphql
+                testEnvironment
+                [graphql|
+                  query {
+                    hasura_article(order_by: [{ id: asc }]) {
+                      id
+
+                      author_by_co_author_id_to_id {
+                        id
+                      }
+                    }
+                  }
+                |]
+
+        actual `shouldBe` expected