Hide (almost all) remaining SQL code in DB module.

[plomtask] / plomtask / db.py

diff --git a/plomtask/db.py b/plomtask/db.py
index f45d2b6adac0e109938d9f8018653cf1caa73fcf..848e750f1a3feccc3d9fb75c192c47a0a4edd4de 100644 (file)
--- a/plomtask/db.py
+++ b/plomtask/db.py
@@ -70,17 +70,34 @@ class DatabaseConnection:
     def rewrite_relations(self, table_name: str, key: str, target: int,
                           rows: list[list[Any]]) -> None:
         """Rewrite relations in table_name to target, with rows values."""
-        self.exec(f'DELETE FROM {table_name} WHERE {key} = ?', (target,))
+        self.delete_where(table_name, key, target)
         for row in rows:
             values = tuple([target] + row)
             q_marks = self.__class__.q_marks_from_values(values)
             self.exec(f'INSERT INTO {table_name} VALUES {q_marks}', values)
 
-    def all_where(self, table_name: str, key: str, target: int) -> list[Row]:
+    def row_where(self, table_name: str, key: str,
+                  target: int | str) -> list[Row]:
         """Return list of Rows at table where key == target."""
         return list(self.exec(f'SELECT * FROM {table_name} WHERE {key} = ?',
                               (target,)))
 
+    def column_where(self, table_name: str, column: str, key: str,
+                     target: int | str) -> list[Any]:
+        """Return column of table where key == target."""
+        return [row[0] for row in
+                self.exec(f'SELECT {column} FROM {table_name} '
+                          f'WHERE {key} = ?', (target,))]
+
+    def column_all(self, table_name: str, column: str) -> list[Any]:
+        """Return complete column of table."""
+        return [row[0] for row in
+                self.exec(f'SELECT {column} FROM {table_name}')]
+
+    def delete_where(self, table_name: str, key: str, target: int) -> None:
+        """Delete from table where key == target."""
+        self.exec(f'DELETE FROM {table_name} WHERE {key} = ?', (target,))
+
     @staticmethod
     def q_marks_from_values(values: tuple[Any]) -> str:
         """Return placeholder to insert values into SQL code."""
@@ -116,8 +133,7 @@ class BaseModel:
             obj = cache[id_]
             from_cache = True
         else:
-            for row in db_conn.exec(f'SELECT * FROM {cls.table_name} '
-                                    'WHERE id = ?', (id_,)):
+            for row in db_conn.row_where(cls.table_name, 'id', id_):
                 obj = cls.from_table_row(db_conn, row)
                 cache[id_] = obj
                 break