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如何使用cqlengine在Cassandra中定义冻结列?

[英]How to define frozen columns in Cassandra using cqlengine?

I'm trying to create a frozen list in Cassandra so that I can use that column as a primary key, I can do that if I run the query manually, 我正在尝试在Cassandra中创建冻结列表,以便可以将该列用作主键,如果我手动运行查询,则可以做到这一点,

some_field frozen <list<int>>

but I'm having a hard time figuring out how to do it using cqlengine in Python, 但是我很难弄清楚如何在Python中使用cqlengine做到这一点,

some_field = columns.List(columns.Integer(), primary_key=True)

How can I accomplish the same thing using cqlengine? 如何使用cqlengine完成同一件事?

EDIT: Final code snippet looks like this, 编辑:最终代码段看起来像这样,

from cassandra.cqlengine import columns
from cassandra.cqlengine.models import Model

class MyModel(Model):
    __table_name__ = 'my_table'
    __options__ = {'compaction': {'class': 'DateTieredCompactionStrategy',
                              'base_time_seconds': 3600,
                              'max_sstable_age_days': 1}}

    keys = columns.Set(columns.Integer(), primary_key=True)
    columns.BaseCollectionColumn._freeze_db_type(keys)
    time_stamp = columns.DateTime(primary_key=True, clustering_order="DESC")
    ...

正如我在源代码中看到的那样 ,创建集合类型后,需要在集合类型的实例上调用_freeze_db_type函数-这会将类型更改为_freeze_db_type frozen<...>

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