2017年10月30日
Sparksql 取代 Hive？
摘要： sparksql hive https://databricks.com/blog/2014/07/01/shark-spark-sql-hive-on-spark-and-the-future-of-sql-on-spark.html https://cwiki.apache.org/conflu 阅读全文
posted @ 2017-10-30 23:43 papering 阅读(674) 评论(0) 推荐(0) 编辑
Eliminates these repeated computation in multi aggregations query
摘要： https://github.com/pingcap/tispark/commit/dcca23bfa1aa0c356a4280d82bc8301c0de08318 阅读全文
posted @ 2017-10-30 20:56 papering 阅读(221) 评论(0) 推荐(0) 编辑
rule-based optimizer cost-based optimizer
摘要： SQL processing uses the following main components to execute a SQL query: The Parser checks both syntax and semantic analysis. The Optimizer uses cost 阅读全文
posted @ 2017-10-30 20:01 papering 阅读(467) 评论(0) 推荐(0) 编辑
Groovy
摘要： https://en.wikipedia.org/wiki/Groovy_(programming_language) Groovy offers simple, consistent syntax for handling lists and maps, reminiscent of Java's 阅读全文
posted @ 2017-10-30 19:54 papering 阅读(200) 评论(0) 推荐(0) 编辑
Interface AutoCloseable
摘要： https://docs.oracle.com/javase/tutorial/essential/exceptions/try.html https://docs.oracle.com/javase/8/docs/api/java/lang/AutoCloseable.html An object 阅读全文
posted @ 2017-10-30 17:20 papering 阅读(239) 评论(0) 推荐(0) 编辑
throws ? catch checked unchecked
摘要： ThrowableClass Error (unchecked) Exception IOException (checked) RuntimeException (unchecked) 阅读全文
posted @ 2017-10-30 14:58 papering 阅读(171) 评论(0) 推荐(0) 编辑
18 ？ 21
摘要： This is for MyHDFSCat = 18+3 阅读全文
posted @ 2017-10-30 10:04 papering 阅读(318) 评论(0) 推荐(0) 编辑