Fix: optimizer join needs on condition

tobymao · Aug 29, 2023 · be56bc0 · be56bc0
1 parent d9f9e2e
commit be56bc0
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Showing 2 changed files with 15 additions and 4 deletions.
diff --git a/sqlglot/optimizer/optimize_joins.py b/sqlglot/optimizer/optimize_joins.py
@@ -72,8 +72,13 @@ def normalize(expression):
         if not any(join.args.get(k) for k in JOIN_ATTRS):
             join.set("kind", "CROSS")
 
-        if join.kind != "CROSS":
+        if join.kind == "CROSS":
+            join.set("on", None)
+        else:
             join.set("kind", None)
+
+            if not join.args.get("on") and not join.args.get("using"):
+                join.set("on", exp.true())
     return expression
 
 

diff --git a/tests/fixtures/optimizer/optimize_joins.sql b/tests/fixtures/optimizer/optimize_joins.sql
@@ -14,19 +14,25 @@ SELECT * FROM x INNER JOIN z ON x.id = z.id;
 SELECT * FROM x JOIN z ON x.id = z.id;
 
 SELECT * FROM x LEFT OUTER JOIN z;
-SELECT * FROM x LEFT JOIN z;
+SELECT * FROM x LEFT JOIN z ON TRUE;
 
 SELECT * FROM x CROSS JOIN z;
 SELECT * FROM x CROSS JOIN z;
 
 SELECT * FROM x JOIN z;
 SELECT * FROM x CROSS JOIN z;
 
+SELECT * FROM x FULL JOIN z;
+SELECT * FROM x FULL JOIN z ON TRUE;
+
 SELECT * FROM x NATURAL JOIN z;
-SELECT * FROM x NATURAL JOIN z;
+SELECT * FROM x NATURAL JOIN z ON TRUE;
 
 SELECT * FROM x RIGHT JOIN z;
-SELECT * FROM x RIGHT JOIN z;
+SELECT * FROM x RIGHT JOIN z ON TRUE;
 
 SELECT * FROM x JOIN z USING (id);
 SELECT * FROM x JOIN z USING (id);
+
+SELECT * FROM x CROSS JOIN z ON TRUE;
+SELECT * FROM x CROSS JOIN z;