fix(oracle): disable dynamic limits

There is working code for this, but the pairing of dynamic limits with
no offsets seems counterintuitive.

ibis/backends/oracle/compiler.py

@@ -12,7 +12,7 @@
 import ibis
 import ibis.common.exceptions as com
 import ibis.expr.operations as ops
-from ibis.backends.base.sqlglot.compiler import NULL, STAR, C, SQLGlotCompiler
+from ibis.backends.base.sqlglot.compiler import NULL, STAR, SQLGlotCompiler
 from ibis.backends.base.sqlglot.datatypes import OracleType
 from ibis.backends.base.sqlglot.rewrites import Window, replace_log2, replace_log10
 from ibis.common.patterns import replace
@@ -207,7 +207,12 @@ def visit_Limit(self, op, *, parent, n, offset):
         if isinstance(n, int):
             result = result.limit(n)
         elif n is not None:
-            result = result.where(C.ROWNUM <= sg.select(n).from_(parent).subquery())
+            raise com.UnsupportedArgumentError(
+                "No support for dynamic limit in the Oracle backend."
+            )
+            # TODO: re-enable this for dynamic limits
+            # but it should be paired with offsets working
+            # result = result.where(C.ROWNUM <= sg.select(n).from_(parent).subquery())
         else:
             assert n is None, n
             if self.no_limit_value is not None:

ibis/backends/tests/test_generic.py

@@ -1408,6 +1408,7 @@ def test_try_cast_func(con, from_val, to_type, func):
                     raises=ExaQueryError,
                     reason="doesn't support OFFSET without ORDER BY",
                 ),
+                pytest.mark.notyet(["oracle"], raises=com.UnsupportedArgumentError),
             ],
         ),
         param(
@@ -1431,6 +1432,7 @@ def test_try_cast_func(con, from_val, to_type, func):
                     raises=ImpalaHiveServer2Error,
                     reason="impala doesn't support OFFSET without ORDER BY",
                 ),
+                pytest.mark.notyet(["oracle"], raises=com.UnsupportedArgumentError),
             ],
         ),
         # positive stop
@@ -1449,6 +1451,7 @@ def test_try_cast_func(con, from_val, to_type, func):
                     raises=ExaQueryError,
                     reason="doesn't support OFFSET without ORDER BY",
                 ),
+                pytest.mark.notyet(["oracle"], raises=com.UnsupportedArgumentError),
             ],
         ),
         param(
@@ -1462,6 +1465,7 @@ def test_try_cast_func(con, from_val, to_type, func):
                     reason="mssql doesn't support OFFSET without LIMIT",
                 ),
                 pytest.mark.notyet(["exasol"], raises=ExaQueryError),
+                pytest.mark.notyet(["oracle"], raises=com.UnsupportedArgumentError),
                 pytest.mark.notyet(
                     ["impala"],
                     raises=ImpalaHiveServer2Error,
@@ -1518,7 +1522,7 @@ def test_static_table_slice(backend, slc, expected_count_fn):
 @pytest.mark.notyet(
     ["oracle"],
     raises=com.UnsupportedArgumentError,
-    reason="backend doesn't support dynamic limit/offset",
+    reason="Removed half-baked dynamic offset functionality for now",
 )
 @pytest.mark.notyet(
     ["trino"],
@@ -1575,6 +1579,11 @@ def test_dynamic_table_slice(backend, slc, expected_count_fn):
     raises=SnowflakeProgrammingError,
     reason="backend doesn't support dynamic limit/offset",
 )
+@pytest.mark.notyet(
+    ["oracle"],
+    raises=com.UnsupportedArgumentError,
+    reason="Removed half-baked dynamic offset functionality for now",
+)
 @pytest.mark.notimpl(
     ["trino"],
     raises=TrinoUserError,