【硬刚Hive】HIVE高级(8):优化(8) Explain 查看执行计划（二）

1 创建测试用表

1）建大表、小表和 JOIN 后表的语句

// 创建大表create table bigtable(id bigint, t bigint, uid string, keyword string, url_rank int, click_num int, click_url string) row format delimited fields terminated by \ ;// 创建小表create table smalltable(id bigint, t bigint, uid string, keyword string, url_rank int, click_num int, click_url string) row format delimited fields terminated by \ ;// 创建 JOIN 后表create table jointable(id bigint, t bigint, uid string, keyword string, url_rank int, click_num int, click_url string) row format delimited fields terminated by \ ;

2）分别向大表和小表中导入数据

hive (default)> load data local inpath /opt/module/data/bigtable into table bigtable;hive (default)> load data local inpath /opt/module/data/smalltable into table smalltable;

2 基本语法

EXPLAIN [EXTENDED | DEPENDENCY | AUTHORIZATION] query-sql