feat(exasol): implement Table.nunique

jcrist · Aug 19, 2024 · a4a8e4b · a4a8e4b
1 parent dab7330
commit a4a8e4b
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Showing 2 changed files with 5 additions and 4 deletions.
diff --git a/ibis/backends/sql/compilers/exasol.py b/ibis/backends/sql/compilers/exasol.py
@@ -192,9 +192,11 @@ def visit_CountStar(self, op, *, arg, where):
         return self.f.count(STAR)
 
     def visit_CountDistinctStar(self, op, *, arg, where):
-        raise com.UnsupportedOperationError(
-            "COUNT(DISTINCT *) is not supported in Exasol"
-        )
+        cols = [sg.column(k, quoted=self.quoted) for k in op.arg.schema.keys()]
+        if where is not None:
+            cols = [self.if_(where, c, NULL) for c in cols]
+        row = sge.Tuple(expressions=cols)
+        return self.f.count(sge.Distinct(expressions=[row]))
 
     def visit_TimestampTruncate(self, op, *, arg, unit):
         short_name = unit.short

diff --git a/ibis/backends/tests/test_aggregation.py b/ibis/backends/tests/test_aggregation.py
@@ -790,7 +790,6 @@ def test_arbitrary(backend, alltypes, df, filtered):
     raises=com.OperationNotDefinedError,
     reason="no one has attempted implementation yet",
 )
-@pytest.mark.notimpl(["exasol"], raises=com.UnsupportedOperationError)
 def test_count_distinct_star(alltypes, df, ibis_cond, pandas_cond):
     table = alltypes[["int_col", "double_col", "string_col"]]
     expr = table.nunique(where=ibis_cond(table))