SELECT stu.name AS stu_name FROM stu WHERE stu.id = %s 2016-05-09 19:23:38,761 INFO sqlalchemy.engine.base.Engine (2,) b >>> print quer2.filter('id=2').scalar() SELECT stu.name AS stu_name FROM stu WHERE id=2 2016-05-09 19:43:47,797 INFO sqlalchemy.engine.base.Engine ...
1. SELECT id FROM 部门表 WHERE NAME='财务部' OR NAME='市场部' 2. SELECT * FROM 员工表 WHERE 部门属性='财务部' OR 部门属性='市场部' 3. SELECT * FROM 员工表 WHERE 部门属性 IN (SELECT id FROM 部门表 WHERE NAME='财务部' OR NAME='市场部') 子查询结果是多行多列: 子查询可以作为...
from sqlalchemy import func print(Session.query(func.count(User.name),User.name).group_by(User.name).all() ) 相当于原生sql为 1 2 SELECT count(user.name) AS count_1, user.name AS user_name FROM user GROUP BY user.name 输出为 [(1, 'Jack'), (2, 'Rain')] 外键关联 我们创建一...
test=> select current_schema(); current_schema --- public (1 row)如上所述,在普通安装的 PostgreSQL 上,默认模式名称是名称public。然而,如果您的数据库用户名与模式名称匹配,PostgreSQL 的默认行为是将该名称用作默认模式。下面,我们使用用户名scott登录。当我们创建一个名为scott的模式时,它会隐式地更改默...
oracle+cx_oracle metadata.reflect(), 250 tables 60.4 6.8 Inspector()的行为变化 对于包含在 SQLite、PostgreSQL、MySQL/MariaDB、Oracle 和 SQL Server 中的 SQLAlchemy 内置方言,Inspector.has_table(),Inspector.has_sequence(),Inspector.has_index(),Inspector.get_table_names()和Inspector.get_sequence_names...
fromsqlalchemy.sqlimportselect s=select([users_table]) result=s.execute()forrowinresult:printrow 结果如下: 首先我们导入select方法,然后我们把表作为一个元素的列表传入,最后我们调用select对象的execute方法,并把结果赋给了result变量,最后就是迭代了。
note to users a fix here is targeted at 2.0. for a decent engine-level configuration to work around this on PostgreSQL, MySQL/MariaDB, SQLite for 1.4/1.3, see #7471 (comment) Describe the bug When you have two tables with the same name o...
To access data from multiple tables simply pass comma separated list of Table instances to the select() function.select([tableOne, tableTwo]) This code would return the Cartesian product of rows present in both the tables. We will learn how to create an SQL JOIN later in this chapter....
are also done by creating a statement object and calling its execute() method. This particular statement is the basic "SELECT * FROM users" with noWHERE clause. Later on we‘ll see how to do WHERE clauses, or only return data from certain columns, or JOIN two (or more) tables together...
of the owningSession. If the given primary key identifier is present in the local identity map, the object is returned directly from this collection and no SQL is emitted, unless the object has been marked fully expired. If not present, a SELECT is performed in order to locate the object....