diff --git a/lib/ecto/adapters/myxql/connection.ex b/lib/ecto/adapters/myxql/connection.ex
index 1c7572aa7..ae378bebf 100644
--- a/lib/ecto/adapters/myxql/connection.ex
+++ b/lib/ecto/adapters/myxql/connection.ex
@@ -914,7 +914,7 @@ if Code.ensure_loaded?(MyXQL) do
     defp fragment_expr(parts, sources, query) do
       Enum.map(parts, fn
         {:raw, part} -> part
-        {:expr, expr} -> expr(expr, sources, query)
+        {:expr, expr} -> op_to_binary(expr, sources, query)
       end)
       |> parens_for_select()
     end
diff --git a/lib/ecto/adapters/postgres/connection.ex b/lib/ecto/adapters/postgres/connection.ex
index 983b335de..45c177cdd 100644
--- a/lib/ecto/adapters/postgres/connection.ex
+++ b/lib/ecto/adapters/postgres/connection.ex
@@ -1165,7 +1165,7 @@ if Code.ensure_loaded?(Postgrex) do
     defp fragment_expr(parts, sources, query) do
       Enum.map(parts, fn
         {:raw, part} -> part
-        {:expr, expr} -> expr(expr, sources, query)
+        {:expr, expr} -> maybe_paren(expr, sources, query)
       end)
       |> parens_for_select()
     end
diff --git a/lib/ecto/adapters/tds/connection.ex b/lib/ecto/adapters/tds/connection.ex
index 7d49c6b3d..c4053b765 100644
--- a/lib/ecto/adapters/tds/connection.ex
+++ b/lib/ecto/adapters/tds/connection.ex
@@ -1010,7 +1010,7 @@ if Code.ensure_loaded?(Tds) do
     defp fragment_expr(parts, sources, query) do
       Enum.map(parts, fn
         {:raw, part} -> part
-        {:expr, expr} -> expr(expr, sources, query)
+        {:expr, expr} -> op_to_binary(expr, sources, query)
       end)
       |> parens_for_select()
     end
diff --git a/test/ecto/adapters/myxql_test.exs b/test/ecto/adapters/myxql_test.exs
index 16a8e9741..34641e0d4 100644
--- a/test/ecto/adapters/myxql_test.exs
+++ b/test/ecto/adapters/myxql_test.exs
@@ -681,6 +681,12 @@ defmodule Ecto.Adapters.MyXQLTest do
     assert_raise Ecto.QueryError, fn ->
       all(query)
     end
+
+    query = Schema |> select([r], fragment("CAST(? AS INT)", r.x and r.y)) |> plan()
+    assert all(query) == ~s{SELECT CAST((s0.`x` AND s0.`y`) AS INT) FROM `schema` AS s0}
+
+    query = Schema |> select([r], fragment("CAST(? AS INT)", r.x or r.y)) |> plan()
+    assert all(query) == ~s{SELECT CAST((s0.`x` OR s0.`y`) AS INT) FROM `schema` AS s0}
   end
 
   test "literals" do
diff --git a/test/ecto/adapters/postgres_test.exs b/test/ecto/adapters/postgres_test.exs
index d283cafbc..cea992a37 100644
--- a/test/ecto/adapters/postgres_test.exs
+++ b/test/ecto/adapters/postgres_test.exs
@@ -861,6 +861,12 @@ defmodule Ecto.Adapters.PostgresTest do
     assert_raise Ecto.QueryError, fn ->
       all(query)
     end
+
+    query = Schema |> select([r], fragment("?::integer", r.x and r.y)) |> plan()
+    assert all(query) == ~s{SELECT (s0."x" AND s0."y")::integer FROM "schema" AS s0}
+
+    query = Schema |> select([r], fragment("?::integer", r.x or r.y)) |> plan()
+    assert all(query) == ~s{SELECT (s0."x" OR s0."y")::integer FROM "schema" AS s0}
   end
 
   test "literals" do
diff --git a/test/ecto/adapters/tds_test.exs b/test/ecto/adapters/tds_test.exs
index c9a01b213..0c45630f7 100644
--- a/test/ecto/adapters/tds_test.exs
+++ b/test/ecto/adapters/tds_test.exs
@@ -719,6 +719,12 @@ defmodule Ecto.Adapters.TdsTest do
                  fn ->
                    all(query)
                  end
+
+    query = Schema |> select([r], fragment("CAST(? AS INT)", r.x and r.y)) |> plan()
+    assert all(query) == ~s{SELECT CAST((s0.[x] AND s0.[y]) AS INT) FROM [schema] AS s0}
+
+    query = Schema |> select([r], fragment("CAST(? AS INT)", r.x or r.y)) |> plan()
+    assert all(query) == ~s{SELECT CAST((s0.[x] OR s0.[y]) AS INT) FROM [schema] AS s0}
   end
 
   test "literals" do