问题描述
在哪里可以找到样本？
我的大部分代码使用ColumnFamilyTemplate对数据记录做CRUD，见下文。一旦我定义了复合键，我仍然可以使用ColumnFamilyTemplate来访问我的具有复合键的数据？
Most of my code using ColumnFamilyTemplate to do CRUD on the data records, see below. Once I have the composite key defined, can I still use ColumnFamilyTemplate to access my data having composite keys?
private static final ColumnFamilyTemplate<UUID, String> template =
new ThriftColumnFamilyTemplate<UUID, String>(
Bootstrap.keyspace,
"User",
UUIDSerializer.get(),
StringSerializer.get(),
HFactory.createMutator(Bootstrap.keyspace, UUIDSerializer.get()));
推荐答案
CRUD上的记录; CompositeType（或DynamicCompositeType）只是另一个类型（例如类似于UUID），它具有对应的串行器（CompositeSerializer）。所以，你的例子可能会变成：
It shouldn't matter which API you use to do the CRUD on the records; CompositeType (or DynamicCompositeType) is just another type (e.g. similar to UUID) which has a corresponding serializer (CompositeSerializer). So, your example might become:
private static final ColumnFamilyTemplate<Composite, String> template =
new ThriftColumnFamilyTemplate<Composite, String>(
Bootstrap.keyspace,
"User",
CompositeSerializer.get(),
StringSerializer.get(),
HFactory.createMutator(Bootstrap.keyspace, CompositeSerializer.get()));
只有额外的功能是在使用模板之前创建Composite（假设组合UUID& Long）
Only extra would be to create the Composite before using template (assume composite of UUID & Long):
Composite key = new Composite();
key.addComponent(someUUID, UUIDSerializer.get());
key.addComponent(someLong, LongSerializer,get());
ColumnFamilyResult<Composite,String> result = template.queryColumns(key);
获取结果时，一种方法是获取密钥的组件：
When fetching results, one way to get the components of the key:
myUUID = result.getKey().get(0, UUIDSerializer.get());
myLong = result.getKey().get(1, LongSerializer,get());
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