# futool-db

数据库操作工具库,基于sqlalchemy实现oracle、postgresql的原生SQL操作

# 一、初始化数据库及建立连接
```python
# oracle
oracle_factory = ConnFactory('oracle', 'xx', 'root@123', 'localhost', 1521, 'XE')
# pg
pg_factory = ConnFactory('postgresql', 'xxx', 'root@123', 'localhost', 5432, 'postgres')
# 获取连接
conn = pg_factory.get_conn()
```
## 连接池配置
```python
class CommonConnector(metaclass=abc.ABCMeta):

    def __init__(self, db_conf: str):
        # 初始化，pool_size可修改初始化连接数,其他参数可参考sqlalchemy连接池配置
        self.engine = create_engine(db_conf, pool_size=15, pool_recycle=3600)
```

# 二、sql操作

## CRUD
```python
from fudb.dbapis.fu_db_api import select_all, select_one, execute_update, batch_insert

        # 返回第一条
        select_one(oracle_factory.get_conn(), 'select * from test limit 20')
        # 查全部
        select_all(oracle_factory.get_conn(), 'select * from test limit 20')
        # 数据量统计
        count(oracle_factory.get_conn(), 'test')
        # delete \insert \update
        execute_update(oracle_factory.get_conn(),'delete from test where id=1')
        # 批量插入
        batch_insert(conn, 'oracle', 'into t_user (id,name,age) values %s', dds, 10)
# 注意：上述方法都会自动关闭连接,如果不想关闭的话可以参考源码进行修改
```
## 事务
```python
    try:
        # 开启事务
        conn.begin()
        # 执行SQL
        rt = conn.execute(text(sql))
        # 提交
        conn.commit()
        # 返回受影响行数,可作为执行是否成功判断依据
        return rt.rowcount
    except Exception as e:
        # 回滚
        conn.rollback()
        raise SqlExecuteError(msg=f'sql [{sql}] 执行失败,开始回滚,e={e}')
    finally:
        # 关闭连接
        conn.close()
```