diff --git a/snowflake_utils/models.py b/snowflake_utils/models.py
index eabacb3..a2b8010 100644
--- a/snowflake_utils/models.py
+++ b/snowflake_utils/models.py
@@ -196,7 +196,6 @@ def bulk_insert(
     def _copy(
         self,
         query: str,
-        query_args: dict,
         path: str,
         file_format: InlineFileFormat | FileFormat,
         storage_integration: str | None = None,
@@ -212,8 +211,7 @@ def _copy(
             if sync_tags and self.table_structure:
                 self.sync_tags(cursor)
             logging.info(f"Starting copy into `{self.fqn}` from path '{path}'")
-            query_args = query_args | {"file_format": file_format}
-            return execute(query.format(**query_args))
+            return execute(query.format(file_format=file_format))
 
     def copy_into(
         self,
@@ -235,7 +233,6 @@ def copy_into(
                 MATCH_BY_COLUMN_NAME={match_by_column_name.value}
                 {self._include_metadata()}
                 """,
-            {},
             path,
             file_format,
             storage_integration,
@@ -274,38 +271,23 @@ def exists(self, cursor: SnowflakeCursor) -> bool:
             ).fetchall()
         )
 
-    def merge(
+    def _merge(
         self,
-        path: str,
-        file_format: InlineFileFormat | FileFormat,
+        copy_callable: callable,
         primary_keys: list[str] = ["id"],
         replication_keys: list[str] | None = None,
-        storage_integration: str | None = None,
-        match_by_column_name: MatchByColumnName = MatchByColumnName.CASE_INSENSITIVE,
         qualify: bool = False,
-    ) -> None:
+    ):
         with connect() as connection:
             cursor = connection.cursor()
             if not self.exists(cursor):
-                self.copy_into(
-                    path=path,
-                    storage_integration=storage_integration,
-                    file_format=file_format,
-                    match_by_column_name=match_by_column_name,
-                    sync_tags=True,
-                )
+                copy_callable(self, sync_tags=True)
                 if qualify:
                     self.qualify(cursor, primary_keys, replication_keys)
                 return None
 
         temp_table = self.model_copy(update={"name": f"{self.name}_temp"})
-        temp_table.copy_into(
-            path=path,
-            storage_integration=storage_integration,
-            file_format=file_format,
-            match_by_column_name=match_by_column_name,
-            full_refresh=True,
-        )
+        copy_callable(temp_table, sync_tags=False)
         if qualify:
             with connect() as connection:
                 cursor = connection.cursor()
@@ -330,6 +312,27 @@ def merge(
                 self.sync_tags(cursor)
             temp_table.drop(cursor)
 
+    def merge(
+        self,
+        path: str,
+        file_format: InlineFileFormat | FileFormat,
+        primary_keys: list[str] = ["id"],
+        replication_keys: list[str] | None = None,
+        storage_integration: str | None = None,
+        match_by_column_name: MatchByColumnName = MatchByColumnName.CASE_INSENSITIVE,
+        qualify: bool = False,
+    ) -> None:
+        def copy_callable(table: Table, sync_tags: bool) -> None:
+            return table.copy_into(
+                path=path,
+                storage_integration=storage_integration,
+                file_format=file_format,
+                match_by_column_name=match_by_column_name,
+                sync_tags=sync_tags,
+            )
+
+        return self._merge(copy_callable, primary_keys, replication_keys, qualify)
+
     def qualify(
         self,
         cursor: SnowflakeCursor,
@@ -455,20 +458,39 @@ def copy_custom(
         full_refresh: bool = False,
         sync_tags: bool = False,
     ) -> None:
-        return self._copy(
+        query = (
             f"""
                 COPY INTO {self.fqn} ({", ".join(column_definitions.keys())})
                 FROM @{self.temporary_stage}/
                 FILE_FORMAT = ( FORMAT_NAME ='{{file_format}}')
                 {self._include_metadata()}
                 """,
-            {},
-            path,
-            file_format,
-            storage_integration,
-            full_refresh,
-            sync_tags,
         )
+        return self._copy(
+            query, path, file_format, storage_integration, full_refresh, sync_tags
+        )
+
+    def merge_custom(
+        self,
+        column_definitions: dict[str, str],
+        path: str,
+        file_format: InlineFileFormat | FileFormat,
+        primary_keys: list[str] = ["id"],
+        replication_keys: list[str] | None = None,
+        storage_integration: str | None = None,
+        qualify: bool = False,
+    ) -> None:
+        def copy_callable(table: Table, sync_tags: bool) -> None:
+            return table.copy_custom(
+                column_definitions,
+                path=path,
+                storage_integration=storage_integration,
+                file_format=file_format,
+                full_refresh=True,
+                sync_tags=sync_tags,
+            )
+
+        return self._merge(copy_callable, primary_keys, replication_keys, qualify)
 
     def setup_connection(
         self, path: str, storage_integration: str, cursor: SnowflakeCursor