Question

enter image description here我正在使用aerospike，在aql中我插入了一些数据，我希望获得有关airospike中特定字段的记录的空值，我在该图片中标记图片一条记录没有名称它的空白空间

Answer 1

Aeropsike是无模式的 - 每条记录都是自我描述的。任何非null的bin都是记录的一部分。任何更新为null的bin实际上都会从记录中删除。因此，请考虑记录单位而不是带有列的表。您可以从记录中查询特定的bin，如果没有找到，Aeropsike将返回null。这是java API：

public final Record get(Policy policy,
         Key key,
         String... binNames)
                 throws AerospikeException
Read record header and bins for specified key. The policy can be used to specify timeouts.
Specified by:
get in interface IAerospikeClient
Parameters:
policy - generic configuration parameters, pass in null for defaults
key - unique record identifier
binNames - bins to retrieve
Returns:
if found, return record instance. If not found, return null.
Throws:
AerospikeException - if read fails

Answer 2

运行一些测试代码 - 记录密钥对其他一些分箱有效：

userRecord = client.get(null, userKey, "notThereBin");
    if (userRecord != null) {
        console.printf("\nINFO: User record with notThereBin read successfully! Here are the details:\n");
        console.printf("notThereBin:  " + userRecord.getValue("notThereBin") + "\n");
    } else {
        console.printf("ERROR: User record not found!\n");
    }

，输出为：

    INFO: User record with notThereBin read successfully! Here are the details:

notThereBin:  null

如何在aerospike

2 个答案: