如何使用bigtable Go客户端支持分页？

问题描述：

I store time series data in bigtable with a rowKey of userId#timestamp. Given query parameters of (userId, startTime, endTime) how can I support pagination i.e return 'limit' records starting from 'offset' ?

note that userId#startTime rowKey may not exist in bigtable but there will some datapoints before and after startTime/EndTime. Bigtable Go client seems to support ReadRows with a prefixRange argument. I could use a prefixRange of userId and 'seek' to the startTime as I iterate using ReadRows but this seems very inefficient if starTime/endTime is way in the past. is there a better way ??

我将时间序列数据存储在具有userId＃timestamp的rowKey的bigtable中。给定（userId，startTime，endTime）的查询参数，我如何支持分页，即从'offset'开始返回'limit'记录？ p>

请注意，在大表中可能不存在userId＃startTime rowKey，但在startTime / EndTime之前和之后会有一些数据点。 Bigtable Go客户端似乎支持带prefixRange参数的ReadRows。当我使用ReadRows进行迭代时，我可以使用userId的prefixRange和'seek'到startTime，但是如果starTime / endTime过去，这似乎效率很低。有更好的方法吗？ p> div>

答

You can start a ReadRows operation from userId#startTime to userId#endTime with a NewRange and set a limit on the number of rows returned with a LimitRows read option.

err = tbl.ReadRows(ctx, NewRange("<userId>#<startTime>", "<userId>#<endTime>"), func(r Row) bool {
    fmt.Println("Got a row")
    return true
}, LimitRows(100))

如何使用bigtable Go客户端支持分页？

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