diff --git a/lib/xmet/db.py b/lib/xmet/db.py
index 9e8d5eb..a17a6f6 100644
--- a/lib/xmet/db.py
+++ b/lib/xmet/db.py
@@ -1,7 +1,7 @@
 import enum
 import sqlite3
 
-from typing import Self
+from typing import Self, Optional, Union, Iterable, Callable
 
 from xmet.config import Config
 
@@ -122,7 +122,7 @@ class Database():
     def from_config(config: Config) -> Self:
         return Database.connect(config['database']['path'])
 
-    def column_placeholders(self, table, obj) -> list:
+    def column_placeholders(self, table: DatabaseTable, obj) -> list:
         ret = list()
 
         for c in table.__columns__:
@@ -133,7 +133,7 @@ class Database():
 
         return ret
 
-    def value_placeholders(self, table, obj) -> list:
+    def value_placeholders(self, table: DatabaseTable, obj) -> list:
         ci = getattr(table, '__columns_write__', None)
 
         ret = list()
@@ -151,7 +151,7 @@ class Database():
 
         return ret
 
-    def row_values(self, table, obj) -> dict:
+    def row_values(self, table: DatabaseTable, obj) -> dict:
         ret = dict()
         vi  = getattr(table, '__values_write__', None)
 
@@ -216,13 +216,21 @@ class Database():
 
         self.db.execute(sql, values)
 
-    def query_sql(self, table, sql, values):
+    def query_sql(self,
+                  table: DatabaseTable,
+                  sql: str,
+                  values: Union[dict, Iterable]):
         cr = DatabaseTableCursor(table, self.db.cursor())
         cr.execute(sql, values)
 
         return cr
 
-    def query(self, table, clauses=list(), values=None, order_by=list(), limit=None):
+    def query(self,
+              table: DatabaseTable,
+              clauses: Iterable=list(),
+              values: Optional[Union[dict, Iterable]]=None,
+              order_by: Iterable=list(),
+              limit: Optional[int]=None):
         selectors = getattr(table, '__columns_read__', None)
 
         if selectors is None:
@@ -262,15 +270,23 @@ class Database():
 
         return self.query_sql(table, sql, values)
 
-    def get_many(self, table, values: dict=dict()):
+    def get_many(self,
+                 table: DatabaseTable,
+                 values: Union[dict, Iterable]=dict()):
         clauses = [f"{k} = :{k}" for k in values]
 
         return self.query(table, clauses, values=values)
 
-    def get(self, table, values: dict=dict()):
+    def get(self,
+            table: DatabaseTable,
+            values: Union[dict, Iterable]=dict()):
         return self.get_many(table, values).fetchone()
 
-    def _call(self, table, fn: str, column: str, values: dict=dict()) -> int:
+    def _call(self,
+              table: DatabaseTable,
+              fn: str,
+              column: str,
+              values: Union[dict, Iterable]=dict()) -> int:
         sql = f"select {fn}({column}) as ret from {table.__table__}"
 
         if len(values) > 0:
@@ -281,11 +297,19 @@ class Database():
 
         return row[0] if row is not None else None
 
-    def min(self, table, column: str, values: dict=dict()) -> int:
+    def min(self,
+            table: DatabaseTable,
+            column: str,
+            values: Union[dict, Iterable]=dict()) -> int:
         return self._call(table, 'min', column, values)
 
-    def max(self, table, column: str, values: dict=dict()) -> int:
+    def max(self,
+            table: DatabaseTable,
+            column: str,
+            values: Union[dict, Iterable]=dict()) -> int:
         return self._call(table, 'max', column, values)
 
-    def count(self, table, values: dict=dict()) -> int:
+    def count(self,
+              table: DatabaseTable,
+              values: Union[dict, Iterable]=dict()) -> int:
         return self._call(table, 'count', table.__key__, values)