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Jaql (JAQL) is a functional data processing and query language most commonly used for JSON query processing on BigData. It started as an Open Source project at Google〔(Original Jaql project )〕 but the latest release was on 7/12/2010. IBM〔(Initial Publication )〕 took it over as primary data processing language for their Hadoop software package (BigInsights ). In addition, MonetDB supports JAQL by an extension called Jaqueline.〔(Jaqueline JAQL Extension of MonetDB )〕 Although having been developed for JSON it supports a variety of other data sources like CSV, TSV, XML. A comparison〔(Comparing High Level MapReduce Query Languages, 9th International Symposium of Advanced Parallel Processing Technologies 2011, Shanghei, China )〕 to other BigData query languages like PIG Latin and Hive QL illustrates performance and usability aspects of these technologies. JAQL supports〔(JAQL in Hadoop, a brief introduction )〕 Lazy Evaluation, so expressions are only materialized when needed. ==Syntax== The basic concept of JAQL is source -> operator(parameter) -> sink ; where a sink can be a source for a downstream operator. So typically a JAQL program has to following structure, expressing a data processing graph: source -> operator1(parameter) -> operator2(parameter) -> operator2(parameter) -> operator3(parameter) -> operator4(parameter) -> sink ; Most commonly for readability reasons JAQL programs are linkbreaked after the arrow, this is also a common technique in Twitter (SCALDING ): source -> operator1(parameter) -> operator2(parameter) -> operator2(parameter) -> operator3(parameter) -> operator4(parameter) -> sink ; 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Jaql」の詳細全文を読む スポンサード リンク
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