Port Python test to Elixir: 12_use_correct_index_test

test/elixir/test/config/suite.elixir

@@ -735,5 +735,17 @@
   ],
   "IgnoreDesignDocsForAllDocsIndexTests": [
     "should not return design docs"
-  ]
+  ],
+  "ChooseCorrectIndexForDocs": [
+    "choose index with one field in index",
+    "choose index with two",
+    "choose index alphabetically",
+    "choose index most accurate",
+    "choose index most accurate in memory selector",
+    "warn on full db scan",
+    "chooses idxA",
+    "can query with range on secondary column",
+    "choose index with id",
+    "choose index with rev"
+  ],
 }

test/elixir/test/mango/12_use_correct_index_test.exs

@@ -0,0 +1,139 @@
+# Licensed under the Apache License, Version 2.0 (the "License"); you may not
+# use this file except in compliance with the License. You may obtain a copy of
+# the License at
+#
+#   http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+# License for the specific language governing permissions and limitations under
+# the License.
+
+defmodule ChooseCorrectIndexForDocs do
+  use CouchTestCase
+
+  @db_name "choose-correct-index"
+  @docs [
+    %{"_id" => "_design/my-design-doc"},
+    %{
+      "_id" => "54af50626de419f5109c962f",
+      "user_id" => 0,
+      "age" => 10,
+      "name" => "Jimi",
+      "location" => "UK",
+      "number" => 4,
+    },
+    %{
+      "_id" => "54af50622071121b25402dc3",
+      "user_id" => 1,
+      "age" => 12,
+      "name" => "Eddie",
+      "location" => "ZAR",
+      "number" => 2,
+    },
+    %{
+      "_id" => "54af50622071121b25402dc6",
+      "user_id" => 1,
+      "age" => 6,
+      "name" => "Harry",
+      "location" => "US",
+      "number" => 8,
+    },
+    %{
+      "_id" => "54af50622071121b25402dc9",
+      "name" => "Eddie",
+      "occupation" => "engineer",
+      "number" => 7,
+    },
+  ]
+  @docs2 [%{"a" => 1, "b" => 1, "c" => 1}, %{"a" => 1000, "d" => 1000, "e" => 1000}]
+
+  setup do
+    MangoDatabase.recreate(@db_name)
+    MangoDatabase.save_docs(@db_name, @docs)
+    :ok
+  end
+
+  test "choose index with one field in index" do
+    MangoDatabase.create_index(@db_name, ["name", "age", "user_id"], ddoc: "aaa")
+    MangoDatabase.create_index(@db_name, ["name"], ddoc: "zzz")
+    {:ok, explain} = MangoDatabase.find(@db_name, %{"name" => "Eddie"}, explain: true)
+    assert explain["index"]["ddoc"] == "_design/zzz"
+  end
+
+  test "choose index with two" do
+    MangoDatabase.create_index(@db_name, ["name", "age", "user_id"], ddoc: "aaa")
+    MangoDatabase.create_index(@db_name, ["name", "age"], ddoc: "bbb")
+    MangoDatabase.create_index(@db_name, ["name"], ddoc: "zzz")
+    {:ok, explain} = MangoDatabase.find(@db_name, %{"name" => "Eddie", "age" => %{"$gte" => 12}}, explain: true)
+    assert explain["index"]["ddoc"] == "_design/bbb"
+  end
+
+  test "choose index alphabetically" do
+    MangoDatabase.create_index(@db_name, ["name"], ddoc: "aaa")
+    MangoDatabase.create_index(@db_name, ["name"], ddoc: "bbb")
+    MangoDatabase.create_index(@db_name, ["name"], ddoc: "zzz")
+    {:ok, explain} = MangoDatabase.find(@db_name, %{"name" => "Eddie", "age" => %{"$gte" => 12}}, explain: true)
+    assert explain["index"]["ddoc"] == "_design/aaa"
+  end
+
+  test "choose index most accurate" do
+    MangoDatabase.create_index(@db_name, ["name", "age", "user_id"], ddoc: "aaa")
+    MangoDatabase.create_index(@db_name, ["name", "age"], ddoc: "bbb")
+    MangoDatabase.create_index(@db_name, ["name"], ddoc: "zzz")
+    {:ok, explain} = MangoDatabase.find(@db_name, %{"name" => "Eddie", "age" => %{"$gte" => 12}}, explain: true)
+    assert explain["index"]["ddoc"] == "_design/bbb"
+  end
+
+  test "choose index most accurate in memory selector" do
+    MangoDatabase.create_index(@db_name, ["name", "location", "user_id"], ddoc: "aaa")
+    MangoDatabase.create_index(@db_name, ["name", "age", "user_id"], ddoc: "bbb")
+    MangoDatabase.create_index(@db_name, ["name"], ddoc: "zzz")
+    {:ok, explain} = MangoDatabase.find(@db_name, %{"name" => "Eddie", "number" => %{"$lte" => 12}}, explain: true)
+    assert explain["index"]["ddoc"] == "_design/zzz"
+  end
+
+  test "warn on full db scan" do
+    selector = %{"not_indexed" => "foo"}
+    {:ok, explain} = MangoDatabase.find(@db_name, selector, explain: true, return_raw: true)
+    assert explain["index"]["type"] == "special"
+    {:ok, resp} = MangoDatabase.find(@db_name, selector, return_raw: true)
+    assert resp["warning"] == "No matching index found, create an index to optimize query time."
+  end
+
+  test "chooses idxA" do
+    MangoDatabase.save_docs(@db_name, @docs2)
+    MangoDatabase.create_index(@db_name, ["a", "b", "c"])
+    MangoDatabase.create_index(@db_name, ["a", "d", "e"])
+    {:ok, explain} = MangoDatabase.find(@db_name,
+      %{"a" => %{"$gt" => 0}, "b" => %{"$gt" => 0}, "c" => %{"$gt" => 0}}, explain: true
+    )
+    assert explain["index"]["def"]["fields"] == [%{"a" => "asc"}, %{"b" => "asc"}, %{"c" => "asc"}]
+  end
+
+  test "can query with range on secondary column" do
+    MangoDatabase.create_index(@db_name, ["age", "name"], ddoc: "bbb")
+    selector = %{"age" => 10, "name" => %{"$gte" => 0}}
+    {:ok, docs} = MangoDatabase.find(@db_name, selector)
+    assert length(docs) == 1
+    {:ok, explain} = MangoDatabase.find(@db_name, selector, explain: true)
+    assert explain["index"]["ddoc"] == "_design/bbb"
+    assert explain["mrargs"]["end_key"] == [10, "<MAX>"]
+  end
+
+  # all documents contain an _id and _rev field they
+  # should not be used to restrict indexes based on the
+  # fields required by the selector
+  test "choose index with id" do
+    MangoDatabase.create_index(@db_name, ["name", "_id"], ddoc: "aaa")
+    {:ok, explain} = MangoDatabase.find(@db_name, %{"name" => "Eddie"}, explain: true)
+    assert explain["index"]["ddoc"] == "_design/aaa"
+  end
+
+  test "choose index with rev" do
+    MangoDatabase.create_index(@db_name, ["name", "_rev"], ddoc: "aaa")
+    {:ok, explain} = MangoDatabase.find(@db_name, %{"name" => "Eddie"}, explain: true)
+    assert explain["index"]["ddoc"] == "_design/aaa"
+  end
+end