feat: 新增技能扩展N9一章相关示例源码

code/newsletter/N9/crud/pw_delete.py

@@ -0,0 +1,35 @@
+import pathlib
+
+import peewee as pw
+
+db_url = pathlib.Path(__file__).parents[1].joinpath("./mydb.sqlite3")
+db = pw.SqliteDatabase(db_url)
+
+
+class BaseModel(pw.Model):
+    class Meta:
+        database = db
+
+
+class User(BaseModel):
+    uid = pw.AutoField()
+    username = pw.CharField(max_length=10)
+
+    def __repr__(self) -> str:
+        return f"User<uid={self.uid}, username={self.username}>"
+
+    __str__ = __repr__
+
+
+def main():
+    user = User.select().where(User.username.startswith("Jay")).get()
+    ok = user.delete_instance()
+    print(f"delete rows: {ok}")
+
+    stmt = User.delete().where(User.username.in_(["bill gates", "larry page"]))
+    ok = stmt.execute()
+    print(f"delete rows: {ok}")
+
+
+if __name__ == '__main__':
+    main()