refactor: Reimplement implicit joiner at expression layer (#436)

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Fixes #<issue_number_goes_here> 🦕

Author: TrevorBergeron

bigframes/core/__init__.py

@@ -28,6 +28,7 @@
 import bigframes.core.nodes as nodes
 from bigframes.core.ordering import OrderingColumnReference
 import bigframes.core.ordering as orderings
+import bigframes.core.rewrite
 import bigframes.core.utils
 from bigframes.core.window_spec import WindowSpec
 import bigframes.dtypes
@@ -351,14 +352,15 @@ def join(
         join_def: join_def.JoinDefinition,
         allow_row_identity_join: bool = False,
     ):
-        return ArrayValue(
-            nodes.JoinNode(
-                left_child=self.node,
-                right_child=other.node,
-                join=join_def,
-                allow_row_identity_join=allow_row_identity_join,
-            )
+        join_node = nodes.JoinNode(
+            left_child=self.node,
+            right_child=other.node,
+            join=join_def,
+            allow_row_identity_join=allow_row_identity_join,
         )
+        if allow_row_identity_join:
+            return ArrayValue(bigframes.core.rewrite.maybe_rewrite_join(join_node))
+        return ArrayValue(join_node)
 
     def _uniform_sampling(self, fraction: float) -> ArrayValue:
         """Sampling the table on given fraction.

bigframes/core/compile/compiler.py

@@ -66,7 +66,6 @@ def compile_join(node: nodes.JoinNode, ordered: bool = True):
             left=left_ordered,
             right=right_ordered,
             join=node.join,
-            allow_row_identity_join=node.allow_row_identity_join,
         )
     else:
         left_unordered = compile_unordered_ir(node.left_child)
@@ -75,7 +74,6 @@ def compile_join(node: nodes.JoinNode, ordered: bool = True):
             left=left_unordered,
             right=right_unordered,
             join=node.join,
-            allow_row_identity_join=node.allow_row_identity_join,
         )