BigTable 设计 - BigTable 单元格大小的上限
我想知道 BigTable 对单元格内容的大小是否有上限。我所说的 BigTable 单元格是指表中特定列族、特定行和特定时间戳的单元格。如果是，那么上限是多少，如果不是，那么在不影响性能的情况下，单元的大小可以扩大到多少？
BigTable论文称每个SSTable文件内部有64Kb块和一个索引。这是否意味着索引的键是行+列+时间戳（其中+表示串联）并且某个键映射的值是对应的64kb单元格？那么这是否意味着 BigTable 单元格不能超过 64 Kb？
谢谢
I want to know if BigTable has an upper limit on the size of cell content. By a BigTable cell, I mean, the cell in the table's specific column family, specific row, and a specific time stamp. If yes, then what is the upper limit, if not, then how much can the size of the cell be scaled up to without adversely affecting performance?
The BigTable paper says that each SSTable File has 64Kb blocks internally and an index. Does this mean that the key to the index is row+column+timestamp (where + represents concatenation) and the value mapped by a certain key the is corresponding cell of 64kb? So does this mean that a BigTable cell cannot exceed more than 64 Kb?
Thanks
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你指的是google对big table的具体实现吗？我想只有谷歌的人才能回答这个问题。
论文本身并没有将单元格限制为 64 kb。虽然它没有提到，但我想单元可以跨越多个 sstable 块。
大表数据模型的两个主要开源实现都允许大于 64kb 的单元格。 Apache Cassandra 的技术限制为 2GB，但实际限制要小得多。 Apache HBase 常见问题解答建议不要使用超过 10mb 的单元大小，但我不确定实际的技术限制。
Are you referring to google's specific implementation of big table? I imagine only someone at google can answer that question.
The paper itself doesn't limit cells to 64 kb. Although it doesn't mention it, I imagine cells can span multiple sstable blocks.
Two of the major open source implementations of the big table data model both allow cells larger than 64kb. Apache Cassandra has a technical limitation of 2gb although the practical limitation is much smaller. The Apache HBase faq recommends not using cell sizes over 10mb, but I'm unsure of the actual technical limitation.
根据 BigTable 文档中的设计您的架构，建议个人价值观的限制和硬性限制。
但值得注意的是，行也有建议和硬限制，并且拥有足够的满足建议/硬限制的单元格可能会远远超过行限制。
According to Designing Your Schema in the BigTable documentation there are recommended limits and hard limits for individual values.
However it is worth noting that there are also recommended and hard limits for rows and having enough cells that meet the recommended/hard limits could well exceed the row limits.