During join planning, don't assume that every TableAlias wraps an implementer of sql.TableNode.

Only tables that support lookups implement sql.TableNode. Table functions that are not backed by an actual table and don't support lookups do not implement this interface.

Author: nicktobey

sql/analyzer/indexed_joins.go

@@ -687,7 +687,10 @@ func addRightSemiJoins(ctx *sql.Context, m *memo.Memo) error {
 		switch n := leftTab.(type) {
 		case *plan.TableAlias:
 			aliasName = n.Name()
-			leftRt = n.Child.(sql.TableNode)
+			leftRt, ok = n.Child.(sql.TableNode)
+			if !ok {
+				return nil
+			}
 		case sql.TableNode:
 			leftRt = n
 		}