BlinkDB is a query engine for executing interactive SQL queries on huge volumes of data and renders query results marked with meaningful error bars. BlinkDB helps users balance ‘query accuracy’ with response time. BlinkDB builds a few stratified samples of the original data and then executes the queries on the samples, rather than the original data in order to reduce the time taken for query execution. The sizes and numbers of the stratified samples are determined by the storage availability specified when importing the data. BlinkDB consists of two main components:
>> Sample building engine: determines the stratified samples to be built based on workload history and data distribution.
>> Dynamic sample selection module: selects the correct sample files at runtime based on the time and/or accuracy requirements of the query.
Posted Date:- 2021-10-22 04:48:36
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