refactor: support agg_ops.RowNumberOp for sqlglot compiler

Author: chelsea-lin

bigframes/core/compile/sqlglot/aggregate_compiler.py

@@ -63,7 +63,7 @@ def compile_analytic(
     window: window_spec.WindowSpec,
 ) -> sge.Expression:
     if isinstance(aggregate, agg_expressions.NullaryAggregation):
-        return nullary_compiler.compile(aggregate.op)
+        return nullary_compiler.compile(aggregate.op, window)
     if isinstance(aggregate, agg_expressions.UnaryAggregation):
         column = typed_expr.TypedExpr(
             scalar_compiler.scalar_op_compiler.compile_expression(aggregate.arg),

bigframes/core/compile/sqlglot/aggregations/nullary_compiler.py

@@ -39,3 +39,15 @@ def _(
     window: typing.Optional[window_spec.WindowSpec] = None,
 ) -> sge.Expression:
     return apply_window_if_present(sge.func("COUNT", sge.convert(1)), window)
+
+
+@NULLARY_OP_REGISTRATION.register(agg_ops.RowNumberOp)
+def _(
+    op: agg_ops.RowNumberOp,
+    window: typing.Optional[window_spec.WindowSpec] = None,
+) -> sge.Expression:
+    result: sge.Expression = sge.func("ROW_NUMBER")
+    if window is None:
+        # ROW_NUMBER always needs an OVER clause.
+        return sge.Window(this=result)
+    return apply_window_if_present(result, window)

bigframes/core/compile/sqlglot/aggregations/unary_compiler.py

@@ -84,10 +84,7 @@ def _(
     column: typed_expr.TypedExpr,
     window: typing.Optional[window_spec.WindowSpec] = None,
 ) -> sge.Expression:
-    # Ranking functions do not support window framing clauses.
-    return apply_window_if_present(
-        sge.func("DENSE_RANK"), window, include_framing_clauses=False
-    )
+    return apply_window_if_present(sge.func("DENSE_RANK"), window)
 
 
 @UNARY_OP_REGISTRATION.register(agg_ops.MaxOp)
@@ -165,10 +162,7 @@ def _(
     column: typed_expr.TypedExpr,
     window: typing.Optional[window_spec.WindowSpec] = None,
 ) -> sge.Expression:
-    # Ranking functions do not support window framing clauses.
-    return apply_window_if_present(
-        sge.func("RANK"), window, include_framing_clauses=False
-    )
+    return apply_window_if_present(sge.func("RANK"), window)
 
 
 @UNARY_OP_REGISTRATION.register(agg_ops.SizeUnaryOp)

bigframes/core/compile/sqlglot/aggregations/windows.py

@@ -25,7 +25,6 @@
 def apply_window_if_present(
     value: sge.Expression,
     window: typing.Optional[window_spec.WindowSpec] = None,
-    include_framing_clauses: bool = True,
 ) -> sge.Expression:
     if window is None:
         return value
@@ -65,7 +64,7 @@ def apply_window_if_present(
     if not window.bounds and not order:
         return sge.Window(this=value, partition_by=group_by)
 
-    if not window.bounds and not include_framing_clauses:
+    if not window.bounds:
         return sge.Window(this=value, partition_by=group_by, order=order)
 
     kind = (

tests/unit/core/compile/sqlglot/aggregations/snapshots/test_nullary_compiler/test_row_number/out.sql

@@ -0,0 +1,13 @@
+WITH `bfcte_0` AS (
+  SELECT
+    `bool_col` AS `bfcol_0`
+  FROM `bigframes-dev`.`sqlglot_test`.`scalar_types`
+), `bfcte_1` AS (
+  SELECT
+    *,
+    ROW_NUMBER() OVER () AS `bfcol_1`
+  FROM `bfcte_0`
+)
+SELECT
+  `bfcol_1` AS `row_number`
+FROM `bfcte_1`

tests/unit/core/compile/sqlglot/aggregations/snapshots/test_nullary_compiler/test_row_number_with_window/out.sql

@@ -0,0 +1,13 @@
+WITH `bfcte_0` AS (
+  SELECT
+    `int64_col` AS `bfcol_0`
+  FROM `bigframes-dev`.`sqlglot_test`.`scalar_types`
+), `bfcte_1` AS (
+  SELECT
+    *,
+    ROW_NUMBER() OVER (ORDER BY `bfcol_0` IS NULL ASC NULLS LAST, `bfcol_0` ASC NULLS LAST) AS `bfcol_1`
+  FROM `bfcte_0`
+)
+SELECT
+  `bfcol_1` AS `row_number`
+FROM `bfcte_1`

tests/unit/core/compile/sqlglot/aggregations/snapshots/test_nullary_compiler/test_size/out.sql

@@ -0,0 +1,12 @@
+WITH `bfcte_0` AS (
+  SELECT
+    `rowindex` AS `bfcol_0`
+  FROM `bigframes-dev`.`sqlglot_test`.`scalar_types`
+), `bfcte_1` AS (
+  SELECT
+    COUNT(1) AS `bfcol_2`
+  FROM `bfcte_0`
+)
+SELECT
+  `bfcol_2` AS `size`
+FROM `bfcte_1`

tests/unit/core/compile/sqlglot/aggregations/test_nullary_compiler.py

@@ -0,0 +1,85 @@
+# Copyright 2025 Google LLC
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import typing
+
+import pytest
+
+from bigframes.core import agg_expressions as agg_exprs
+from bigframes.core import array_value, identifiers, nodes, ordering, window_spec
+from bigframes.operations import aggregations as agg_ops
+import bigframes.pandas as bpd
+
+pytest.importorskip("pytest_snapshot")
+
+
+def _apply_nullary_agg_ops(
+    obj: bpd.DataFrame,
+    ops_list: typing.Sequence[agg_exprs.NullaryAggregation],
+    new_names: typing.Sequence[str],
+) -> str:
+    aggs = [(op, identifiers.ColumnId(name)) for op, name in zip(ops_list, new_names)]
+
+    agg_node = nodes.AggregateNode(obj._block.expr.node, aggregations=tuple(aggs))
+    result = array_value.ArrayValue(agg_node)
+
+    sql = result.session._executor.to_sql(result, enable_cache=False)
+    return sql
+
+
+def _apply_nullary_window_op(
+    obj: bpd.DataFrame,
+    op: agg_exprs.NullaryAggregation,
+    window_spec: window_spec.WindowSpec,
+    new_name: str,
+) -> str:
+    win_node = nodes.WindowOpNode(
+        obj._block.expr.node,
+        expression=op,
+        window_spec=window_spec,
+        output_name=identifiers.ColumnId(new_name),
+    )
+    result = array_value.ArrayValue(win_node).select_columns([new_name])
+
+    sql = result.session._executor.to_sql(result, enable_cache=False)
+    return sql
+
+
+def test_size(scalar_types_df: bpd.DataFrame, snapshot):
+    bf_df = scalar_types_df
+    agg_expr = agg_ops.SizeOp().as_expr()
+    sql = _apply_nullary_agg_ops(bf_df, [agg_expr], ["size"])
+
+    snapshot.assert_match(sql, "out.sql")
+
+
+def test_row_number(scalar_types_df: bpd.DataFrame, snapshot):
+    bf_df = scalar_types_df
+    agg_expr = agg_exprs.NullaryAggregation(agg_ops.RowNumberOp())
+    window = window_spec.WindowSpec()
+    sql = _apply_nullary_window_op(bf_df, agg_expr, window, "row_number")
+
+    snapshot.assert_match(sql, "out.sql")
+
+
+def test_row_number_with_window(scalar_types_df: bpd.DataFrame, snapshot):
+    col_name = "int64_col"
+    bf_df = scalar_types_df[[col_name, "int64_too"]]
+    agg_expr = agg_exprs.NullaryAggregation(agg_ops.RowNumberOp())
+
+    window = window_spec.WindowSpec(ordering=(ordering.ascending_over(col_name),))
+    # window = window_spec.unbound(ordering=(ordering.ascending_over(col_name),ordering.ascending_over("int64_too")))
+    sql = _apply_nullary_window_op(bf_df, agg_expr, window, "row_number")
+
+    snapshot.assert_match(sql, "out.sql")