OpenStack 数据库操作 demo

 1 #!/usr/bin/env python
 2 
 3 from sqlalchemy.orm import sessionmaker
 4 from sqlalchemy import create_engine
 5 from sqlalchemy.ext.declarative import declarative_base
 6 from sqlalchemy import Column, Integer, String, Float, Boolean
 7 
 8 sql_connection = "mysql+pymysql://nova:[email protected]:3306/nova" 
 9 engine = create_engine(sql_connection, echo=True)
10 Session = sessionmaker(bind=engine)
11 session = Session()
12 
13 BASE = declarative_base() 
14 
15 class InstanceTypes(BASE):
16     __tablename__ = "instance_types" 
17 
18     id = Column(Integer, primary_key=True)
19     name = Column(String(255))
20     memory_mb = Column(Integer)
21     vcpus = Column(Integer)
22     root_gb = Column(Integer)
23     ephemeral_gb = Column(Integer)
24     flavorid = Column(String(255))
25     swap = Column(Integer, nullable=False, default=0)
26     rxtx_factor = Column(Float, nullable=False, default=1)
27     vcpu_weight = Column(Integer, nullable=True)
28     disabled = Column(Boolean, default=False)
29     is_public = Column(Boolean, default=True)
30 
31 flavors = session.query(InstanceTypes).all()
32 
33 for flavor in flavors:
34     print flavor.id, flavor.name

执行结果：

[root@controller ~]# python sql.py
2018-11-01 22:35:08,943 INFO sqlalchemy.engine.base.Engine SHOW VARIABLES LIKE 'sql_mode'
2018-11-01 22:35:08,943 INFO sqlalchemy.engine.base.Engine ()
2018-11-01 22:35:08,944 INFO sqlalchemy.engine.base.Engine SELECT DATABASE()
2018-11-01 22:35:08,944 INFO sqlalchemy.engine.base.Engine ()
2018-11-01 22:35:08,944 INFO sqlalchemy.engine.base.Engine show collation where `Charset` = 'utf8' and `Collation` = 'utf8_bin'
2018-11-01 22:35:08,944 INFO sqlalchemy.engine.base.Engine ()
2018-11-01 22:35:08,946 INFO sqlalchemy.engine.base.Engine SELECT CAST('test plain returns' AS CHAR(60)) AS anon_1
2018-11-01 22:35:08,946 INFO sqlalchemy.engine.base.Engine ()
2018-11-01 22:35:08,946 INFO sqlalchemy.engine.base.Engine SELECT CAST('test unicode returns' AS CHAR(60)) AS anon_1
2018-11-01 22:35:08,947 INFO sqlalchemy.engine.base.Engine ()
2018-11-01 22:35:08,947 INFO sqlalchemy.engine.base.Engine SELECT CAST('test collated returns' AS CHAR CHARACTER SET utf8) COLLATE utf8_bin AS anon_1
2018-11-01 22:35:08,947 INFO sqlalchemy.engine.base.Engine ()
2018-11-01 22:35:08,948 INFO sqlalchemy.engine.base.Engine BEGIN (implicit)
2018-11-01 22:35:08,949 INFO sqlalchemy.engine.base.Engine SELECT instance_types.id AS instance_types_id, instance_types.name AS instance_types_name, instance_types.memory_mb AS instance_types_memory_mb, instance_types.vcpus AS instance_types_vcpus, instance_types.root_gb AS instance_types_root_gb, instance_types.ephemeral_gb AS instance_types_ephemeral_gb, instance_types.flavorid AS instance_types_flavorid, instance_types.swap AS instance_types_swap, instance_types.rxtx_factor AS instance_types_rxtx_factor, instance_types.vcpu_weight AS instance_types_vcpu_weight, instance_types.disabled AS instance_types_disabled, instance_types.is_public AS instance_types_is_public
FROM instance_types
2018-11-01 22:35:08,949 INFO sqlalchemy.engine.base.Engine ()
1 m1.medium
2 m1.tiny
3 m1.large
4 m1.xlarge
5 m1.small
6 4Vcpu_4096Mem_50Disk_disk0type
7 m1.vcomputer