diff --git a/mindsdb_sql/parser/ast/select/case.py b/mindsdb_sql/parser/ast/select/case.py
index 02fa827..1ae0df0 100644
--- a/mindsdb_sql/parser/ast/select/case.py
+++ b/mindsdb_sql/parser/ast/select/case.py
@@ -4,13 +4,14 @@
 
 
 class Case(ASTNode):
-    def __init__(self, rules, default=None, *args, **kwargs):
+    def __init__(self, rules, default=None, arg=None, *args, **kwargs):
         super().__init__(*args, **kwargs)
 
         # structure:
         # [
         #   [ condition, result ]
         # ]
+        self.arg = arg
         self.rules = rules
         self.default = default
 
@@ -36,7 +37,12 @@ def to_tree(self, *args, level=0, **kwargs):
         if self.default is not None:
             default_str = f'{ind1}default => {self.default.to_string()}\n'
 
+        arg_str = ''
+        if self.arg is not None:
+            arg_str = f'{ind1}arg => {self.arg.to_string()}\n'
+
         return f'{ind}Case(\n' \
+               f'{arg_str}'\
                f'{rules_str}\n' \
                f'{default_str}' \
                f'{ind})'
@@ -53,4 +59,8 @@ def get_string(self, *args, alias=True, **kwargs):
         default_str = ''
         if self.default is not None:
             default_str = f' ELSE {self.default.to_string()}'
-        return f"CASE {rules_str}{default_str} END"
+
+        arg_str = ''
+        if self.arg is not None:
+            arg_str = f'{self.arg.to_string()} '
+        return f"CASE {arg_str}{rules_str}{default_str} END"
diff --git a/mindsdb_sql/parser/ast/select/operation.py b/mindsdb_sql/parser/ast/select/operation.py
index d7cad6a..e208d43 100644
--- a/mindsdb_sql/parser/ast/select/operation.py
+++ b/mindsdb_sql/parser/ast/select/operation.py
@@ -98,12 +98,13 @@ def get_string(self, *args, **kwargs):
 
 
 class WindowFunction(ASTNode):
-    def __init__(self, function, partition=None, order_by=None, alias=None):
+    def __init__(self, function, partition=None, order_by=None, alias=None, modifier=None):
         super().__init__()
         self.function = function
         self.partition = partition
         self.order_by = order_by
         self.alias = alias
+        self.modifier = modifier
 
     def to_tree(self, *args, level=0, **kwargs):
         fnc_str = self.function.to_tree(level=level+2)
@@ -143,7 +144,8 @@ def to_string(self, *args, **kwargs):
             alias_str = self.alias.to_string()
         else:
             alias_str = ''
-        return f'{fnc_str} over({partition_str} {order_str}) {alias_str}'
+        modifier_str = ' ' + self.modifier if self.modifier else ''
+        return f'{fnc_str} over({partition_str} {order_str}{modifier_str}) {alias_str}'
 
 
 class Object(ASTNode):
@@ -177,7 +179,12 @@ def __init__(self, info):
         super().__init__(op='interval', args=[info, ])
 
     def get_string(self, *args, **kwargs):
-        return f'INTERVAL {self.args[0]}'
+
+        arg = self.args[0]
+        items = arg.split(' ', maxsplit=1)
+        # quote first element
+        items[0] = f"'{items[0]}'"
+        return "INTERVAL " + " ".join(items)
 
     def to_tree(self, *args, level=0, **kwargs):
         return self.get_string( *args, **kwargs)
diff --git a/mindsdb_sql/parser/dialects/mindsdb/parser.py b/mindsdb_sql/parser/dialects/mindsdb/parser.py
index 5186024..ae13959 100644
--- a/mindsdb_sql/parser/dialects/mindsdb/parser.py
+++ b/mindsdb_sql/parser/dialects/mindsdb/parser.py
@@ -1352,6 +1352,15 @@ def column_list(self, p):
     def case(self, p):
         return Case(rules=p.case_conditions, default=getattr(p, 'expr', None))
 
+    @_('CASE expr case_conditions ELSE expr END',
+       'CASE expr case_conditions END')
+    def case(self, p):
+        if hasattr(p, 'expr'):
+            arg, default = p.expr, None
+        else:
+            arg, default = p.expr0, p.expr1
+        return Case(rules=p.case_conditions, default=default, arg=arg)
+
     @_('case_condition',
        'case_conditions case_condition')
     def case_conditions(self, p):
@@ -1364,13 +1373,18 @@ def case_condition(self, p):
         return [p.expr0, p.expr1]
 
     # Window function
-    @_('function OVER LPAREN window RPAREN')
+    @_('expr OVER LPAREN window RPAREN',
+       'expr OVER LPAREN window id BETWEEN id id AND id id RPAREN')
     def window_function(self, p):
 
+        modifier = None
+        if hasattr(p, 'BETWEEN'):
+            modifier = f'{p.id0} BETWEEN {p.id1} {p.id2} AND {p.id3} {p.id4}'
         return WindowFunction(
-            function=p.function,
+            function=p.expr,
             order_by=p.window.get('order_by'),
             partition=p.window.get('partition'),
+            modifier=modifier,
         )
 
     @_('window PARTITION_BY expr_list')
diff --git a/mindsdb_sql/planner/query_planner.py b/mindsdb_sql/planner/query_planner.py
index 05910ee..ff25b4f 100644
--- a/mindsdb_sql/planner/query_planner.py
+++ b/mindsdb_sql/planner/query_planner.py
@@ -229,6 +229,19 @@ def find_objects(node, is_table, **kwargs):
                     mdb_entities.append(node)
 
         query_traversal(query, find_objects)
+
+        # cte names are not mdb objects
+        if query.cte:
+            cte_names = [
+                cte.name.parts[-1]
+                for cte in query.cte
+            ]
+            mdb_entities = [
+                item
+                for item in mdb_entities
+                if '.'.join(item.parts) not in cte_names
+            ]
+
         return {
             'mdb_entities': mdb_entities,
             'integrations': integrations,
@@ -672,6 +685,16 @@ def plan_delete(self, query: Delete):
         ))
 
     def plan_cte(self, query):
+        query_info = self.get_query_info(query)
+
+        if (
+            len(query_info['integrations']) == 1
+            and len(query_info['mdb_entities']) == 0
+            and len(query_info['user_functions']) == 0
+        ):
+            # single integration, will be planned later
+            return
+
         for cte in query.cte:
             step = self.plan_select(cte.query)
             name = cte.name.parts[-1]
diff --git a/mindsdb_sql/render/sqlalchemy_render.py b/mindsdb_sql/render/sqlalchemy_render.py
index 745a8a9..929f262 100644
--- a/mindsdb_sql/render/sqlalchemy_render.py
+++ b/mindsdb_sql/render/sqlalchemy_render.py
@@ -293,10 +293,15 @@ def prepare_case(self, t: ast.Case):
             conditions.append(
                 (self.to_expression(condition), self.to_expression(result))
             )
+        default = None
         if t.default is not None:
-            conditions.append(self.to_expression(t.default))
+            default = self.to_expression(t.default)
 
-        return sa.case(*conditions)
+        value = None
+        if t.arg is not None:
+            value = self.to_expression(t.arg)
+
+        return sa.case(*conditions, else_=default, value=value)
 
     def to_function(self, t):
         op = getattr(sa.func, t.op)
diff --git a/tests/test_parser/test_base_sql/test_select_structure.py b/tests/test_parser/test_base_sql/test_select_structure.py
index 07f8abe..b7a6543 100644
--- a/tests/test_parser/test_base_sql/test_select_structure.py
+++ b/tests/test_parser/test_base_sql/test_select_structure.py
@@ -1026,6 +1026,40 @@ def test_case(self):
         assert ast.to_tree() == expected_ast.to_tree()
         assert str(ast) == str(expected_ast)
 
+    def test_case_simple_form(self):
+        sql = f'''SELECT
+                    CASE R.DELETE_RULE
+                        WHEN 'CASCADE' THEN 0
+                        WHEN 'SET NULL' THEN 2
+                        ELSE 3
+                    END AS DELETE_RULE
+                   FROM COLLATIONS'''
+        ast = parse_sql(sql)
+
+        expected_ast = Select(
+            targets=[
+                Case(
+                    arg=Identifier('R.DELETE_RULE'),
+                    rules=[
+                        [
+                            Constant('CASCADE'),
+                            Constant(0)
+                        ],
+                        [
+                            Constant('SET NULL'),
+                            Constant(2)
+                        ]
+                    ],
+                    default=Constant(3),
+                    alias=Identifier('DELETE_RULE')
+                )
+            ],
+            from_table=Identifier('COLLATIONS')
+        )
+
+        assert ast.to_tree() == expected_ast.to_tree()
+        assert str(ast) == str(expected_ast)
+
     def test_select_left(self):
         sql = f'select left(a, 1) from tab1'
         ast = parse_sql(sql)
@@ -1152,3 +1186,23 @@ def test_table_double_quote(self):
 
         ast = parse_sql(sql)
         assert str(ast) == str(expected_ast)
+
+    def test_window_function_mindsdb(self):
+
+        # modifier
+        query = "select SUM(col0) OVER (partition by col1 order by col2 rows between unbounded preceding and current row) from table1 "
+        expected_ast = Select(
+            targets=[
+                WindowFunction(
+                    function=Function(op='sum', args=[Identifier('col0')]),
+                    partition=[Identifier('col1')],
+                    order_by=[OrderBy(field=Identifier('col2'))],
+                    modifier='rows BETWEEN unbounded preceding AND current row'
+                )
+            ],
+            from_table=Identifier('table1')
+        )
+        ast = parse_sql(query)
+        assert str(ast) == str(expected_ast)
+        assert ast.to_tree() == expected_ast.to_tree()
+
diff --git a/tests/test_planner/test_integration_select.py b/tests/test_planner/test_integration_select.py
index 5180465..faa8831 100644
--- a/tests/test_planner/test_integration_select.py
+++ b/tests/test_planner/test_integration_select.py
@@ -554,7 +554,7 @@ def test_select_from_table_subselect_api_integration(self):
         plan = plan_query(
             query,
             integrations=[{'name': 'int1', 'class_type': 'api', 'type': 'data'}],
-            predictor_metadata=[{'name': 'pred', 'integration_name': 'mindsdb'}]
+            predictor_metadata=[{'name': 'pred', 'integration_name': 'mindsdb'}],
         )
 
         assert plan.steps == expected_plan.steps
@@ -583,6 +583,47 @@ def test_select_from_table_subselect_sql_integration(self):
 
         assert plan.steps == expected_plan.steps
 
+    def test_select_from_single_integration(self):
+        sql_parsed = '''
+            with tab2 as (
+              select * from int1.tabl2
+            )
+            select x from tab2
+            join int1.tab1 on 0=0
+            where x1 in (select id from int1.tab1)
+            limit 1
+        '''
+
+        sql_integration = '''
+            with tab2 as (
+              select * from tabl2
+            )
+            select x from tab2
+            join tab1 on 0=0
+            where x1 in (select id as id from tab1)
+            limit 1
+        '''
+        query = parse_sql(sql_parsed, dialect='mindsdb')
+
+        expected_plan = QueryPlan(
+            predictor_namespace='mindsdb',
+            steps=[
+                FetchDataframeStep(
+                    integration='int1',
+                    query=parse_sql(sql_integration),
+                ),
+            ],
+        )
+
+        plan = plan_query(
+            query,
+            integrations=[{'name': 'int1', 'class_type': 'sql', 'type': 'data'}],
+            predictor_metadata=[{'name': 'pred', 'integration_name': 'mindsdb'}],
+            default_namespace='mindsdb',
+        )
+
+        assert plan.steps == expected_plan.steps
+
     def test_delete_from_table_subselect_api_integration(self):
         query = parse_sql('''
             delete from int1.tab1