Question

我在python中有以下类，并且使用cqlengine作为cassandra DB的对象映射器，

class Company(Model):
    id = columns.Integer(index=True, primary_key=True)
    company_name = columns.Text(required=False)
    created_at = columns.DateTime(default=datetime.now)

class Social(Model):
    id = columns.Integer(index=True, primary_key=True)
    name = columns.Text(required=False)

class UserCompany(Model):
    id = columns.Integer(index=True, primary_key=True)
    user_id = columns.Integer(required=True)
    company_id = columns.Integer(required=True)

array_of_tables=[UserCompany, Company, Social]
    for table in array_of_tables:
        sync_table(table)

问题：执行代码时，无法在cassandra中创建两个以上的表。

Erorr留言：

  File "test.py", line 109, in <module>
    create_tables()
  File "test.py", line 68, in create_tables
    sync_table(table)
  File "/usr/lib64/python2.6/site-packages/cassandra/cqlengine/management.py", line 259, in sync_table
    execute(qs)
  File "/usr/lib64/python2.6/site-packages/cassandra/cqlengine/connection.py", line 171, in execute
    result = session.execute(query, params, timeout=timeout)
  File "cassandra/cluster.py", line 1602, in cassandra.cluster.Session.execute (cassandra/cluster.c:27334)
  File "cassandra/cluster.py", line 3347, in cassandra.cluster.ResponseFuture.result (cassandra/cluster.c:65206)
cassandra.InvalidRequest: code=2200 [Invalid query] message="Cannot create secondary index on partition key column id"

需要您帮助解决此问题。

Answer 1

不允许设置主列的索引。我刚刚从代码中删除它，它工作。它应该如下所示。在这里，我只使用了UUID而不是整数仍然与实际问题无关。

class Company(Model):
    id = columns.UUID(default=uuid.uuid1(), primary_key=True))
    company_name = columns.Text(required=False)
    created_at = columns.DateTime(default=datetime.now)

class Social(Model):
    id = columns.UUID(default=uuid.uuid1(), primary_key=True)
    name = columns.Text(required=False)

class UserCompany(Model):
    id = columns.UUID(default=uuid.uuid1(), primary_key=True)
    user_id = columns.Integer(required=True)
    company_id = columns.Integer(required=True)

array_of_tables=[UserCompany, Company, Social]
    for table in array_of_tables:
        sync_table(table)

无法使用cqlengine中的sync_table（）创建两个以上的表

1 个答案: