feat(risingwave): support include_null in first/last aggs

Author: cpcloud

ibis/backends/sql/compilers/risingwave.py

@@ -1,5 +1,6 @@
 from __future__ import annotations
 
+import sqlglot as sg
 import sqlglot.expressions as sge
 
 import ibis.common.exceptions as com
@@ -40,25 +41,23 @@ def visit_DateNow(self, op):
         return self.cast(sge.CurrentTimestamp(), dt.date)
 
     def visit_First(self, op, *, arg, where, order_by, include_null):
-        if include_null:
-            raise com.UnsupportedOperationError(
-                "`include_null=True` is not supported by the risingwave backend"
-            )
         if not order_by:
             raise com.UnsupportedOperationError(
                 "RisingWave requires an `order_by` be specified in `first`"
             )
+        if not include_null:
+            cond = arg.is_(sg.not_(NULL, copy=False))
+            where = cond if where is None else sge.And(this=cond, expression=where)
         return self.agg.first_value(arg, where=where, order_by=order_by)
 
     def visit_Last(self, op, *, arg, where, order_by, include_null):
-        if include_null:
-            raise com.UnsupportedOperationError(
-                "`include_null=True` is not supported by the risingwave backend"
-            )
         if not order_by:
             raise com.UnsupportedOperationError(
                 "RisingWave requires an `order_by` be specified in `last`"
             )
+        if not include_null:
+            cond = arg.is_(sg.not_(NULL, copy=False))
+            where = cond if where is None else sge.And(this=cond, expression=where)
         return self.agg.last_value(arg, where=where, order_by=order_by)
 
     def visit_Correlation(self, op, *, left, right, how, where):

ibis/backends/tests/test_aggregation.py

@@ -647,23 +647,16 @@ def test_first_last(alltypes, method, filtered, include_null):
     raises=com.OperationNotDefinedError,
 )
 @pytest.mark.parametrize("method", ["first", "last"])
-@pytest.mark.parametrize("filtered", [False, True])
+@pytest.mark.parametrize("filtered", [False, True], ids=["not-filtered", "filtered"])
 @pytest.mark.parametrize(
     "include_null",
     [
-        False,
+        param(False, id="exclude-null"),
         param(
             True,
             marks=[
                 pytest.mark.notimpl(
-                    [
-                        "clickhouse",
-                        "exasol",
-                        "flink",
-                        "postgres",
-                        "risingwave",
-                        "snowflake",
-                    ],
+                    ["clickhouse", "exasol", "flink", "postgres", "snowflake"],
                     raises=com.UnsupportedOperationError,
                     reason="`include_null=True` is not supported",
                 ),
@@ -674,6 +667,7 @@ def test_first_last(alltypes, method, filtered, include_null):
                     strict=False,
                 ),
             ],
+            id="include-null",
         ),
     ],
 )