是否有人经历过表格的询问。
select * from TableX where columnY = Z limit some_limits
例如:
select * from Topics where category_id = 100
页: 1 Y被指数化,但并非主要关键。 ColumnY = Z可以退回无法预测的几行(从零到几千)。
我只想知道数据集非常大的情况,例如表X中的1 000多万件。 这种询问的表现如何?
业绩的细微细节应当是独一无二的(例如,我指的是具体的大型-O分析)。
It depends upon the records found. If your query return a large number of records it may take time to load the browswer. And even larger return could make your browser unresponsive. But this is how you execute the query. The better solution for such problems could be limiting the query as you did with relevant limits. Further more instead of limiting manually you may use limit with loop till certain index and again start from following index in the case of programming. I am answering with the context of programming. Hope this answers your question
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