use :prefix to query attached databases

CHANGELOG.md

@@ -7,6 +7,11 @@ project adheres to [Semantic Versioning][semver].
 
 ## Unreleased
 
+- changed: Reimplement querying prefix names.
+- added: Raise on cross-database foreign keys.
+- changed: Made `quote_name/1` private.
+- changed: quote_name no longer accepts names with double quote.
+
 ## v0.25.0
 - fixed: Precedence issues with SQL generation. See [#182](https://github.com/elixir-sqlite/ecto_sqlite3/pull/182)
 

integration_test/prefix_test.exs

@@ -0,0 +1,21 @@
+defmodule Ecto.Integration.PrefixTest do
+  use Ecto.Integration.Case, async: true
+
+  import Ecto.Query, only: [from: 2]
+
+  alias Ecto.Integration.Post
+  alias Ecto.Integration.TestRepo
+
+  test "queries an attached database through :prefix" do
+    TestRepo.query!(~s|ATTACH DATABASE ":memory:" AS "foo"|)
+    TestRepo.query!(~s|CREATE TABLE "foo"."posts" AS SELECT * FROM "main"."posts"|)
+
+    TestRepo.insert!(%Post{id: 1}, prefix: "foo")
+
+    results =
+      from(Post, prefix: "foo")
+      |> TestRepo.all()
+
+    assert [%Post{id: 1}] = results
+  end
+end

integration_test/test_helper.exs

@@ -90,8 +90,11 @@ excludes = [
   # which is not true for SQLite
   :lock_for_migrations,
 
-  # Migration we don't support
+  # sadly we can not run prefix tests since ecto_sql's integration test expects
+  # attached db to persist across connections
   :prefix,
+
+  # Migration we don't support
   :add_column_if_not_exists,
   :remove_column_if_exists,
   :alter_primary_key,

lib/ecto/adapters/sqlite3/connection.ex

@@ -271,7 +271,7 @@ defmodule Ecto.Adapters.SQLite3.Connection do
   def insert(prefix, table, [], [[]], on_conflict, returning, [], _opts) do
     [
       "INSERT INTO ",
-      quote_table(prefix, table),
+      quote_name(prefix, table),
       insert_as(on_conflict),
       " DEFAULT VALUES",
       returning(returning)
@@ -290,7 +290,7 @@ defmodule Ecto.Adapters.SQLite3.Connection do
 
     [
       "INSERT INTO ",
-      quote_table(prefix, table),
+      quote_name(prefix, table),
       insert_as(on_conflict),
       values,
       on_conflict(on_conflict, header),
@@ -313,7 +313,7 @@ defmodule Ecto.Adapters.SQLite3.Connection do
 
     [
       "UPDATE ",
-      quote_table(prefix, table),
+      quote_name(prefix, table),
       " SET ",
       fields,
       " WHERE ",
@@ -335,7 +335,7 @@ defmodule Ecto.Adapters.SQLite3.Connection do
 
     [
       "DELETE FROM ",
-      quote_table(prefix, table),
+      quote_name(prefix, table),
       " WHERE ",
       filters,
       returning(returning)
@@ -402,7 +402,7 @@ defmodule Ecto.Adapters.SQLite3.Connection do
     [
       [
         "CREATE TABLE ",
-        quote_table(table.prefix, table.name),
+        quote_name(table.prefix, table.name),
         ?\s,
         ?(,
         column_definitions(table, columns),
@@ -421,7 +421,7 @@ defmodule Ecto.Adapters.SQLite3.Connection do
     [
       [
         "CREATE TABLE IF NOT EXISTS ",
-        quote_table(table.prefix, table.name),
+        quote_name(table.prefix, table.name),
         ?\s,
         ?(,
         column_definitions(table, columns),
@@ -437,7 +437,7 @@ defmodule Ecto.Adapters.SQLite3.Connection do
     [
       [
         "DROP TABLE ",
-        quote_table(table.prefix, table.name)
+        quote_name(table.prefix, table.name)
       ]
     ]
   end
@@ -450,7 +450,7 @@ defmodule Ecto.Adapters.SQLite3.Connection do
     [
       [
         "DROP TABLE IF EXISTS ",
-        quote_table(table.prefix, table.name)
+        quote_name(table.prefix, table.name)
       ]
     ]
   end
@@ -463,7 +463,7 @@ defmodule Ecto.Adapters.SQLite3.Connection do
     Enum.map(changes, fn change ->
       [
         "ALTER TABLE ",
-        quote_table(table.prefix, table.name),
+        quote_name(table.prefix, table.name),
         ?\s,
         column_change(table, change)
       ]
@@ -498,9 +498,9 @@ defmodule Ecto.Adapters.SQLite3.Connection do
         "CREATE ",
         if_do(index.unique, "UNIQUE "),
         "INDEX ",
-        quote_name(index.name),
+        quote_name(index.prefix, index.name),
         " ON ",
-        quote_table(index.prefix, index.table),
+        quote_name(index.table),
         " (",
         fields,
         ?),
@@ -517,9 +517,9 @@ defmodule Ecto.Adapters.SQLite3.Connection do
         "CREATE ",
         if_do(index.unique, "UNIQUE "),
         "INDEX IF NOT EXISTS ",
-        quote_name(index.name),
+        quote_name(index.prefix, index.name),
         " ON ",
-        quote_table(index.prefix, index.table),
+        quote_name(index.table),
         " (",
         fields,
         ?),
@@ -532,7 +532,7 @@ defmodule Ecto.Adapters.SQLite3.Connection do
     [
       [
         "DROP INDEX ",
-        quote_table(index.prefix, index.name)
+        quote_name(index.prefix, index.name)
       ]
     ]
   end
@@ -545,7 +545,7 @@ defmodule Ecto.Adapters.SQLite3.Connection do
     [
       [
         "DROP INDEX IF EXISTS ",
-        quote_table(index.prefix, index.name)
+        quote_name(index.prefix, index.name)
       ]
     ]
   end
@@ -558,9 +558,9 @@ defmodule Ecto.Adapters.SQLite3.Connection do
     [
       [
         "ALTER TABLE ",
-        quote_table(current_table.prefix, current_table.name),
+        quote_name(current_table.prefix, current_table.name),
         " RENAME TO ",
-        quote_table(nil, new_table.name)
+        quote_name(nil, new_table.name)
       ]
     ]
   end
@@ -569,7 +569,7 @@ defmodule Ecto.Adapters.SQLite3.Connection do
     [
       [
         "ALTER TABLE ",
-        quote_table(table.prefix, table.name),
+        quote_name(table.prefix, table.name),
         " RENAME COLUMN ",
         quote_name(current_column),
         " TO ",
@@ -1539,7 +1539,7 @@ defmodule Ecto.Adapters.SQLite3.Connection do
 
       {table, schema, prefix} ->
         name = as_prefix ++ [create_alias(table) | Integer.to_string(pos)]
-        {quote_table(prefix, table), name, schema}
+        {quote_name(prefix, table), name, schema}
 
       %Ecto.SubQuery{} ->
         {nil, as_prefix ++ [?s | Integer.to_string(pos)], nil}
@@ -1658,7 +1658,7 @@ defmodule Ecto.Adapters.SQLite3.Connection do
   defp check_expr(nil), do: []
 
   defp check_expr(%{name: name, expr: expr}),
-    do: [" CONSTRAINT ", name, " CHECK (", expr, ")"]
+    do: [" CONSTRAINT ", quote_name(name), " CHECK (", expr, ")"]
 
   defp collate_expr(nil), do: []
 
@@ -1717,11 +1717,13 @@ defmodule Ecto.Adapters.SQLite3.Connection do
   defp reference_expr(%Reference{with: [_]}, _table, _name), do: []
 
   defp reference_expr(%Reference{} = ref, table, name) do
+    assert_same_database(table.prefix, ref.prefix)
+
     [
       " CONSTRAINT ",
       reference_name(ref, table, name),
       " REFERENCES ",
-      quote_table(ref.prefix || table.prefix, ref.table),
+      quote_name(ref.table),
       ?(,
       quote_name(ref.column),
       ?),
@@ -1826,13 +1828,15 @@ defmodule Ecto.Adapters.SQLite3.Connection do
   end
 
   defp composite_fk_definition(table, {_op, name, ref, _opts}) do
+    assert_same_database(table.prefix, ref.prefix)
+
     {current_columns, reference_columns} = Enum.unzip([{name, ref.column} | ref.with])
 
     [
       ", FOREIGN KEY (",
       quote_names(current_columns),
       ") REFERENCES ",
-      quote_table(ref.prefix || table.prefix, ref.table),
+      quote_name(ref.table),
       ?(,
       quote_names(reference_columns),
       ?),
@@ -1855,24 +1859,32 @@ defmodule Ecto.Adapters.SQLite3.Connection do
 
   defp quote_names(names), do: Enum.map_intersperse(names, ?,, &quote_name/1)
 
-  def quote_name(name), do: quote_entity(name)
+  defp quote_name(nil, name), do: quote_name(name)
 
-  def quote_table(table), do: quote_entity(table)
+  defp quote_name(prefix, name), do: [quote_name(prefix), ?., quote_name(name)]
 
-  defp quote_table(nil, name), do: quote_entity(name)
-
-  defp quote_table(prefix, _name) when is_atom(prefix) or is_binary(prefix) do
-    raise ArgumentError, "SQLite3 does not support table prefixes"
+  defp quote_name(val) when is_atom(val) do
+    quote_name(Atom.to_string(val))
   end
 
-  defp quote_table(_, name), do: quote_entity(name)
+  defp quote_name(val) when is_binary(val) do
+    # Don't introduce unnecessary complexity and align with Ecto.Adapters.Postgres.Connection.
+    #
+    # Although SQLite and Postgres both allow syntax like:
+    # ```sql
+    # CREATE TABLE "lookma""quotes"(id INTEGER);
+    # SELECT name    FROM sqlite_schema WHERE name    = 'lookma"quotes';
+    # SELECT relname FROM pg_class      WHERE relname = 'lookma"quotes';
+    # ```
+    # there isn't much practical use case for it.
+    if String.contains?(val, "\"") do
+      raise ArgumentError,
+            "bad literal/field/index/table name #{inspect(val)} (\" is not permitted)"
+    end
 
-  defp quote_entity(val) when is_atom(val) do
-    quote_entity(Atom.to_string(val))
+    [[?", val, ?"]]
   end
 
-  defp quote_entity(val), do: [[?", val, ?"]]
-
   defp intersperse_reduce(list, separator, user_acc, reducer, acc \\ [])
 
   defp intersperse_reduce([], _separator, user_acc, _reducer, acc),
@@ -1903,4 +1915,27 @@ defmodule Ecto.Adapters.SQLite3.Connection do
     |> escape_string()
     |> :binary.replace("\"", "\\\"", [:global])
   end
+
+  # We know this holds since exqlite does not export sqlite3_db_config from Sqlite3NIF,
+  # thus nobody can call sqlite3_db_config(db, SQLITE_DBCONFIG_MAINDBNAME, ...)
+  defp normalize_database_name(nil) do
+    # TODO: handle modifier-selected temp database somehow?
+    # src/parse.y: `temp(A) ::= TEMP.  {A = pParse->db->init.busy==0;}`
+    "main"
+  end
+
+  defp normalize_database_name(name) when is_atom(name) do
+    normalize_database_name(Atom.to_string(name))
+  end
+
+  defp normalize_database_name(name) when is_binary(name) do
+    String.downcase(name, :ascii)
+  end
+
+  defp assert_same_database(table_prefix, ref_prefix) do
+    if normalize_database_name(ref_prefix || table_prefix) !=
+         normalize_database_name(table_prefix) do
+      raise ArgumentError, "SQLite3 does not support cross-database foreign keys"
+    end
+  end
 end

test/ecto/adapters/sqlite3/connection/delete_all_test.exs

@@ -65,20 +65,20 @@ defmodule Ecto.Adapters.SQLite3.Connection.DeleteAllTest do
   end
 
   test "delete all with prefix" do
-    assert_raise ArgumentError, "SQLite3 does not support table prefixes", fn ->
+    query =
       Schema
       |> Ecto.Queryable.to_query()
       |> Map.put(:prefix, "prefix")
       |> plan()
-      |> delete_all()
-    end
 
-    assert_raise ArgumentError, "SQLite3 does not support table prefixes", fn ->
+    assert delete_all(query) == ~s{DELETE FROM "prefix"."schema" AS s0}
+
+    query =
       Schema
       |> from(prefix: "first")
       |> Map.put(:prefix, "prefix")
       |> plan()
-      |> delete_all()
-    end
+
+    assert delete_all(query) == ~s{DELETE FROM "first"."schema" AS s0}
   end
 end

test/ecto/adapters/sqlite3/connection/delete_test.exs

@@ -6,5 +6,11 @@ defmodule Ecto.Adapters.SQLite3.DeleteTest do
   test "delete" do
     query = delete(nil, "schema", [x: 1, y: 2], [])
     assert query == ~s{DELETE FROM "schema" WHERE "x" = ? AND "y" = ?}
+
+    query = delete("prefix", "schema", [x: 1, y: 2], [])
+    assert query == ~s{DELETE FROM "prefix"."schema" WHERE "x" = ? AND "y" = ?}
+
+    query = delete(nil, "schema", [x: nil, y: 2], [])
+    assert query == ~s{DELETE FROM "schema" WHERE "x" IS NULL AND "y" = ?}
   end
 end

test/ecto/adapters/sqlite3/connection/insert_test.exs

@@ -25,9 +25,8 @@ defmodule Ecto.Adapters.SQLite3.Connection.InsertTest do
     query = insert(nil, "schema", [], [[]], {:raise, [], []}, [])
     assert query == ~s{INSERT INTO "schema" DEFAULT VALUES}
 
-    assert_raise ArgumentError, "SQLite3 does not support table prefixes", fn ->
-      insert("prefix", "schema", [], [[]], {:raise, [], []}, [])
-    end
+    assert insert("prefix", "schema", [], [[]], {:raise, [], []}, []) ==
+             ~s{INSERT INTO "prefix"."schema" DEFAULT VALUES}
 
     query = insert(nil, "schema", [:x, :y], [[:x, :y]], {:raise, [], []}, [:id])
     assert query == ~s{INSERT INTO "schema" ("x","y") VALUES (?1,?2) RETURNING "id"}