Python操作Cassandra数据库

from cassandra.cluster import Cluster

cluster = Cluster(contact_points=['127.0.0.1'], port=9042)
session = cluster.connect()

# select data from remote DB
session.execute('use system')

# 写入数据
def write_data(rows):
    session.execute(
        "insert into system.model_service_new (owner, model_name, port, service_name) values ("
        "%s, %s, %s, %s)", rows)
    cluster.shutdown()
    return "success"
 

# 删除数据
def delete_data(service_name):`
    session.execute('use system')
    session.execute('delete from system.model_service_new where \"service_name\"='
                    '\'%s\';' % (service_name,))
    cluster.shutdown()
    return "success"
 

# 查询数据
def obtain_port(service_name):`
    rows = session.execute(
        'select * from system.model_service_new where \"service_name\"=\'%s\' allow filtering;' % (
            service_name))
    cluster.shutdown()
    return rows

　　

 

说明：Cassandra数据库默认端口是9042。需要注意的是，查询数据后，数据库返回的是一个对象，假如我们需要取值，则要使用这个对象的某个方法。假设对象为x，其中某个字段为y,则x.y表示为该对象中，y的值。