如何访问BigQuery结果集的cacheHit属性? [英] How do I access the cacheHit property of my BigQuery result set?

问题描述

显然，当使用BigQuery API时，BigQuery结果有一个cacheHit属性.我尝试找到此属性，但不确定如何访问它.这是我使用BigQuery API的Java代码. cacheHit不是我得到的TableResult tr的属性:

Apparently, when using the BigQuery API, there is a cacheHit property of a BigQuery result. I've tried finding this property and I'm not sure how I need to access it. Here's my Java code that uses the BigQuery API. cacheHit isn't a property of the TableResult tr that I get:

try
{
    QueryJobConfiguration queryJobConfiguration =

        QueryJobConfiguration.newBuilder(
                "mySQLqueryText"
        )
        .setUseLegacySql(false)
        .setAllowLargeResults(false)
        .setUseQueryCache(true)
        .build();

    try {
        TableResult tr = bigQuery.query(queryJobConfiguration);

        Iterable<FieldValueList> rowList = tr.getValues();

        ....
    }
    catch (BigQueryException e) {
        // do stuff
    }
} catch (InterruptedException e) {
    e.printStackTrace();
}

我看了这个问题- BigQuery cacheHit属性

...但是那不是Java，而且我还没有找到我可以使用的任何results()属性，如该问题所示.

... but that's not Java, and I haven't found any results() property I can use, as suggested in that question.

这里有一些有关 JobStatistics2 的文档.对象，显然具有cacheHit属性.

There's some documentation here about the JobStatistics2 object, that apparently has a cacheHit property.

我可以得到一个JobStatistics(不是一个JobStatistics2对象)，像这样:

I can get a JobStatistics (not a JobStatistics2 object), like this:

QueryJobConfiguration queryJobConfiguration =

    QueryJobConfiguration.newBuilder(
            "myQueryString"
    )
    .setUseLegacySql(false)
    .setAllowLargeResults(false)
    .setUseQueryCache(true)
    .build();

    JobId jobId = JobId.of(UUID.randomUUID().toString());
    Job queryJob = bigQuery.create(JobInfo.newBuilder(queryJobConfiguration).setJobId(jobId).build());

try {

    queryJob = queryJob.waitFor();

    if (queryJob != null) {

        JobStatistics js = queryJob.getStatistics();

    Iterable<FieldValueList> rowList = bigQuery.query(queryJobConfiguration).getValues();

...但是我在js上看不到任何cacheHit属性.当我尝试创建JobStatistics2时，通过更改实例化JobStatistics的行，如下所示:

... but I don't see any cacheHit property on js. When I try creating a JobStatistics2 instead, by changing the line where I'm instantiating JobStatistics, like this:

JobStatistics2 js = queryJob.getStatistics();

我收到错误Type parameter S has incompatible upper bounds: JobStatistics and JobStatistics2.这并不意味着什么，当我搜索Google错误时，没有任何有用的结果.

I get an error Type parameter S has incompatible upper bounds: JobStatistics and JobStatistics2. This doesn't mean much, and when I Google the error there are no useful results.

我觉得Google文档没有太大用处.如何访问cacheHit属性，并仍然获得代码示例中所示的rowList?

I'm not finding the Google documentation too useful. How can I access the cacheHit property, and still obtain my rowList as shown in the code example?

推荐答案

QueryStatistics是JobStatistics的嵌套类之一，可以看到

QueryStatistics is one of the nested classes of JobStatistics as can be seen here and has a getCacheHit() method:

import com.google.cloud.bigquery.JobStatistics.QueryStatistics;

...

QueryStatistics js = queryJob.getStatistics();

System.out.println(js.getCacheHit());

请参见完整代码此处用于我的测试.

See full code here for my test.

关于JobStatistics2，这是针对com.google.api.services.bigquery库而不是com.google.cloud.bigquery.在这种情况下，您可以使用 .

Regarding JobStatistics2 this is for com.google.api.services.bigquery library and not com.google.cloud.bigquery. In that case you could use getQuery() from JobStatistics to get a JobStatistics2 object and then use getCacheHit().

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