Adding upstream version 6.0.4.

Signed-off-by: Daniel Baumann <daniel@debian.org>

tests/fixtures/optimizer/optimizer.sql

@@ -0,0 +1,148 @@
+SELECT a, m FROM z LATERAL VIEW EXPLODE([1, 2]) q AS m;
+SELECT
+  "z"."a" AS "a",
+  "q"."m" AS "m"
+FROM (
+  SELECT
+    "z"."a" AS "a"
+  FROM "z" AS "z"
+) AS "z"
+LATERAL VIEW
+EXPLODE(ARRAY(1, 2)) q AS "m";
+
+SELECT x FROM UNNEST([1, 2]) AS q(x, y);
+SELECT
+  "q"."x" AS "x"
+FROM UNNEST(ARRAY(1, 2)) AS "q"("x", "y");
+
+WITH cte AS (
+    (
+        SELECT
+            a
+            FROM
+            x
+    )
+    UNION ALL
+    (
+        SELECT
+            a
+        FROM
+            y
+    )
+)
+SELECT
+    *
+FROM
+    cte;
+WITH "cte" AS (
+  (
+    SELECT
+      "x"."a" AS "a"
+    FROM "x" AS "x"
+  )
+  UNION ALL
+  (
+    SELECT
+      "y"."a" AS "a"
+    FROM "y" AS "y"
+  )
+)
+SELECT
+  "cte"."a" AS "a"
+FROM "cte";
+
+WITH cte1 AS (
+    SELECT a
+    FROM x
+), cte2 AS (
+    SELECT a + 1 AS a
+    FROM cte1
+)
+SELECT
+    a
+FROM cte1
+UNION ALL
+SELECT
+    a
+FROM cte2;
+WITH "cte1" AS (
+  SELECT
+    "x"."a" AS "a"
+  FROM "x" AS "x"
+), "cte2" AS (
+  SELECT
+    "cte1"."a" + 1 AS "a"
+  FROM "cte1"
+)
+SELECT
+  "cte1"."a" AS "a"
+FROM "cte1"
+UNION ALL
+SELECT
+  "cte2"."a" AS "a"
+FROM "cte2";
+
+SELECT a, SUM(b)
+FROM (
+    SELECT x.a, y.b
+    FROM x, y
+    WHERE (SELECT max(b) FROM y WHERE x.a = y.a) >= 0 AND x.a = y.a
+) d
+WHERE (TRUE AND TRUE OR 'a' = 'b') AND a > 1
+GROUP BY a;
+SELECT
+  "d"."a" AS "a",
+  SUM("d"."b") AS "_col_1"
+FROM (
+  SELECT
+    "x"."a" AS "a",
+    "y"."b" AS "b"
+  FROM (
+    SELECT
+      "x"."a" AS "a"
+    FROM "x" AS "x"
+    WHERE
+      "x"."a" > 1
+  ) AS "x"
+  LEFT JOIN (
+    SELECT
+      MAX("y"."b") AS "_col_0",
+      "y"."a" AS "_u_1"
+    FROM "y" AS "y"
+    GROUP BY
+      "y"."a"
+  ) AS "_u_0"
+    ON "x"."a" = "_u_0"."_u_1"
+  JOIN (
+    SELECT
+      "y"."a" AS "a",
+      "y"."b" AS "b"
+    FROM "y" AS "y"
+  ) AS "y"
+    ON "x"."a" = "y"."a"
+  WHERE
+    "_u_0"."_col_0" >= 0
+    AND NOT "_u_0"."_u_1" IS NULL
+) AS "d"
+GROUP BY
+  "d"."a";
+
+(SELECT a FROM x) LIMIT 1;
+(
+  SELECT
+    "x"."a" AS "a"
+  FROM "x" AS "x"
+)
+LIMIT 1;
+
+(SELECT b FROM x UNION SELECT b FROM y) LIMIT 1;
+(
+  SELECT
+    "x"."b" AS "b"
+  FROM "x" AS "x"
+  UNION
+  SELECT
+    "y"."b" AS "b"
+  FROM "y" AS "y"
+)
+LIMIT 1;