Add support for cross lateral joins. (#458)

Author: wilkinson4

lib/ecto/adapters/myxql/connection.ex

@@ -388,6 +388,7 @@ if Code.ensure_loaded?(MyXQL) do
     end
 
     defp join_on(:cross, true, _sources, _query), do: []
+    defp join_on(:cross_lateral, true, _sources, _query), do: []
     defp join_on(_qual, expr, sources, query), do: [" ON " | expr(expr, sources, query)]
 
     defp join_qual(:inner, _), do: " INNER JOIN "
@@ -397,6 +398,7 @@ if Code.ensure_loaded?(MyXQL) do
     defp join_qual(:right, _), do: " RIGHT OUTER JOIN "
     defp join_qual(:full, _),  do: " FULL OUTER JOIN "
     defp join_qual(:cross, _), do: " CROSS JOIN "
+    defp join_qual(:cross_lateral, _), do: " CROSS JOIN LATERAL "
 
     defp where(%{wheres: wheres} = query, sources) do
       boolean(" WHERE ", wheres, sources, query)

lib/ecto/adapters/postgres/connection.ex

@@ -510,6 +510,7 @@ if Code.ensure_loaded?(Postgrex) do
     end
 
     defp join_on(:cross, true, _sources, _query), do: []
+    defp join_on(:cross_lateral, true, _sources, _query), do: []
     defp join_on(_qual, expr, sources, query), do: [" ON " | expr(expr, sources, query)]
 
     defp join_qual(:inner), do: "INNER JOIN "
@@ -519,6 +520,7 @@ if Code.ensure_loaded?(Postgrex) do
     defp join_qual(:right), do: "RIGHT OUTER JOIN "
     defp join_qual(:full),  do: "FULL OUTER JOIN "
     defp join_qual(:cross), do: "CROSS JOIN "
+    defp join_qual(:cross_lateral), do: "CROSS JOIN LATERAL "
 
     defp where(%{wheres: wheres} = query, sources) do
       boolean(" WHERE ", wheres, sources, query)

lib/ecto/adapters/tds/connection.ex

@@ -526,6 +526,7 @@ if Code.ensure_loaded?(Tds) do
     defp join_qual(:cross), do: "CROSS JOIN "
     defp join_qual(:inner_lateral), do: "CROSS APPLY "
     defp join_qual(:left_lateral), do: "OUTER APPLY "
+    defp join_qual(:cross_lateral), do: error!(nil, "cross lateral joins are not supported in the Tds Adapter")
 
     defp where(%Query{wheres: wheres} = query, sources) do
       boolean(" WHERE ", wheres, sources, query)

mix.exs

@@ -77,7 +77,7 @@ defmodule EctoSQL.MixProject do
     if path = System.get_env("ECTO_PATH") do
       {:ecto, path: path}
     else
-      {:ecto, "~> 3.9.0"}
+      {:ecto, "~> 3.10.0-dev", github: "elixir-ecto/ecto"}
     end
   end
 

mix.lock

@@ -6,7 +6,7 @@
   "decimal": {:hex, :decimal, "2.0.0", "a78296e617b0f5dd4c6caf57c714431347912ffb1d0842e998e9792b5642d697", [:mix], [], "hexpm", "34666e9c55dea81013e77d9d87370fe6cb6291d1ef32f46a1600230b1d44f577"},
   "deep_merge": {:hex, :deep_merge, "0.2.0", "c1050fa2edf4848b9f556fba1b75afc66608a4219659e3311d9c9427b5b680b3", [:mix], [], "hexpm", "e3bf435a54ed27b0ba3a01eb117ae017988804e136edcbe8a6a14c310daa966e"},
   "earmark_parser": {:hex, :earmark_parser, "1.4.29", "149d50dcb3a93d9f3d6f3ecf18c918fb5a2d3c001b5d3305c926cddfbd33355b", [:mix], [], "hexpm", "4902af1b3eb139016aed210888748db8070b8125c2342ce3dcae4f38dcc63503"},
-  "ecto": {:hex, :ecto, "3.9.0", "7c74fc0d950a700eb7019057ff32d047ed7f19b57c1b2ca260cf0e565829101d", [:mix], [{:decimal, "~> 1.6 or ~> 2.0", [hex: :decimal, repo: "hexpm", optional: false]}, {:jason, "~> 1.0", [hex: :jason, repo: "hexpm", optional: true]}, {:telemetry, "~> 0.4 or ~> 1.0", [hex: :telemetry, repo: "hexpm", optional: false]}], "hexpm", "fed5ebc5831378b916afd0b5852a0c5bb3e7390665cc2b0ec8ab0c712495b73d"},
+  "ecto": {:git, "https://github.com/elixir-ecto/ecto.git", "96d4920339d5d645dedaed1ef2ce7428683f529d", []},
   "ex_doc": {:hex, :ex_doc, "0.29.0", "4a1cb903ce746aceef9c1f9ae8a6c12b742a5461e6959b9d3b24d813ffbea146", [:mix], [{:earmark_parser, "~> 1.4.19", [hex: :earmark_parser, repo: "hexpm", optional: false]}, {:makeup_elixir, "~> 0.14", [hex: :makeup_elixir, repo: "hexpm", optional: false]}, {:makeup_erlang, "~> 0.1", [hex: :makeup_erlang, repo: "hexpm", optional: false]}], "hexpm", "f096adb8bbca677d35d278223361c7792d496b3fc0d0224c9d4bc2f651af5db1"},
   "jason": {:hex, :jason, "1.4.0", "e855647bc964a44e2f67df589ccf49105ae039d4179db7f6271dfd3843dc27e6", [:mix], [{:decimal, "~> 1.0 or ~> 2.0", [hex: :decimal, repo: "hexpm", optional: true]}], "hexpm", "79a3791085b2a0f743ca04cec0f7be26443738779d09302e01318f97bdb82121"},
   "makeup": {:hex, :makeup, "1.1.0", "6b67c8bc2882a6b6a445859952a602afc1a41c2e08379ca057c0f525366fc3ca", [:mix], [{:nimble_parsec, "~> 1.2.2 or ~> 1.3", [hex: :nimble_parsec, repo: "hexpm", optional: false]}], "hexpm", "0a45ed501f4a8897f580eabf99a2e5234ea3e75a4373c8a52824f6e873be57a6"},

test/ecto/adapters/myxql_test.exs

@@ -1006,6 +1006,18 @@ defmodule Ecto.Adapters.MyXQLTest do
            ~s{WHERE ((s0.`id` > 0) AND (s0.`id` < ?))}
   end
 
+  test "cross lateral join with fragment" do
+    query = Schema
+            |> join(:cross_lateral, [p], q in fragment("SELECT * FROM schema2 AS s2 WHERE s2.id = ? AND s2.field = ?", p.x, ^10))
+            |> select([p, q], {p.id, q.z})
+            |> where([p], p.id > 0 and p.id < ^100)
+            |> plan()
+    assert all(query) ==
+           ~s{SELECT s0.`id`, f1.`z` FROM `schema` AS s0 CROSS JOIN LATERAL } <>
+           ~s{(SELECT * FROM schema2 AS s2 WHERE s2.id = s0.`x` AND s2.field = ?) AS f1 } <>
+           ~s{WHERE ((s0.`id` > 0) AND (s0.`id` < ?))}
+  end
+
   test "cross join" do
     query = from(p in Schema, cross_join: c in Schema2, select: {p.id, c.id}) |> plan()
     assert all(query) ==

test/ecto/adapters/postgres_test.exs

@@ -1162,6 +1162,18 @@ defmodule Ecto.Adapters.PostgresTest do
            ~s{WHERE ((s0."id" > 0) AND (s0."id" < $2))}
   end
 
+  test "cross lateral join with fragment" do
+    query = Schema
+            |> join(:cross_lateral, [p], q in fragment("SELECT * FROM schema2 AS s2 WHERE s2.id = ? AND s2.field = ?", p.x, ^10))
+            |> select([p, q], {p.id, q.z})
+            |> where([p], p.id > 0 and p.id < ^100)
+            |> plan()
+    assert all(query) ==
+           ~s{SELECT s0."id", f1."z" FROM "schema" AS s0 CROSS JOIN LATERAL } <>
+           ~s{(SELECT * FROM schema2 AS s2 WHERE s2.id = s0."x" AND s2.field = $1) AS f1 } <>
+           ~s{WHERE ((s0."id" > 0) AND (s0."id" < $2))}
+  end
+
   test "cross join" do
     query = from(p in Schema, cross_join: c in Schema2, select: {p.id, c.id}) |> plan()
     assert all(query) ==