在 Spark 或 Hive 中，我们可以使用 LATERAL VIEW + EXPLODE 或 POSEXPLODE 将 array 或者 map 里面的数据由行转成列，这个操作在数据分析里面很常见。比如我们有以下表：[code lang="sql"]CREATE TABLE `default`.`iteblog_explode` ( `id` INT, `items` ARRAY<STRING>)[/code]表里面的数据如下：[code lang="sql"]spark-sql> SELECT * FROM iteblog_explode;1 ["iteblog.co w397090770 3年前 (2022-08-08) 2046℃ 0评论7喜欢
Presto 在 Facebook 的诞生最开始是为了填补当时 Facebook 内部实时查询和 ETL 处理之间的空白。Presto 的核心目标就是提供交互式查询，也就是我们常说的 Ad-Hoc Query，很多公司都使用它作为 OLAP 计算引擎。但是随着近年来业务场景越来越复杂，除了交互式查询场景，很多公司也需要批处理；但是 Presto 作为一个 MPP 计算引擎，将一个 MPP 体 w397090770 3年前 (2022-06-23) 1691℃ 0评论3喜欢
Depending on the complexity of your SQL query there are many, often exponential, query plans that return the same result. However, the performance of each plan can vary drastically; taking only seconds to finish or days given the chosen plan.That places a significant burden on analysts who will then have to know how to write performant SQL. This problem gets worse as the complexity of questions and SQL queries increases. In the abse w397090770 3年前 (2022-04-20) 659℃ 0评论1喜欢
Starburst provides connectors to the most popular data sources included in many of these connectors are a number of exclusive enhancements. Many of Starburst’s connectors when compared with open source Trino have enhanced extensions such as parallelism, pushdown and table statistics, that drastically improve the overall performance. Parallelism distributes query processing across workers, and uses many connections to the data source a w397090770 3年前 (2022-04-15) 645℃ 0评论0喜欢
Dynamic filtering optimizations significantly improve the performance of queries with selective joins by avoiding reading of data that would be filtered by join condition. In this respect, dynamic filtering is similar to join pushdown discussed above, however it is the equivalent of inner join pushdown across data sources. As a consequence we derive the performance benefits associated with selective joins when performing federated queri w397090770 3年前 (2022-04-15) 456℃ 0评论1喜欢
Trino Summit 2021 由 Starburst 于 2021年10月21日-22日通过线上的方式进行。主要分享嘉宾有 Trino 的几个创始人、Apache Iceberg 的创建者 Ryan Blue 以及来自 DoorDash 的 Akshat Nair 和 Satya Boora 等。如果想及时了解Spark、Hadoop或者HBase相关的文章，欢迎关注微信公众号：iteblog_hadoop主要分享议题State of TrinoFast results using Iceberg and TrinoThe Future of w397090770 3年前 (2022-04-12) 627℃ 0评论4喜欢
