我们要运用subquery来找出所有在西部的店的营业额。我们可以用下面的 SQL 来达到我们的目的: SELECT SUM(Sales) FROM Store_Information WHERE Store_name IN (SELECT store_name FROM Geography WHERE region_name = 'West'); 结果: SUM(Sales) 2050 在这个例子中,我们并没有直接将两个表格连接起来,然后由此直...
SELECTSEGMENT_NAME,SUM(BYTES/1024/1024)mFROMDBA_SEGMENTSWHERESEGMENT_NAMENOTIN(select index_name from dba_indexes whereUNIQUENESS='NONUNIQUE')GROUPBYSEGMENT_NAME; 耗时一分钟,为什么这么慢呢?在SQL语句where子查询后有not in、not exists、in、exists时,CBO会尝试将子查询展开(unnest)消除filter,但是上面的例...
使用IN的子查询时,在子查询的返回结果中会自动去除NULL值的记录。 使用示例 示例1:使用格式1子查询语法。命令示例如下。 set odps.sql.allow.fullscan=true; select * from sale_detail where total_price in (select total_price from shop); 返回结果如下: +---+---+---+---+---+ | shop_name ...
SQL Delete Join SQL Select Top Syntax # There is no general syntax. Subqueries are regular queries placed inside parenthesis. Subqueries can be used in different ways and at different locations inside a query. A subquery with the IN operator. ...
通过上述逻辑计划和物理计划可以看出,SparkSQL在对not in subquery处理,从逻辑计划转换为物理计划时,会最终选择BroadcastNestedLoopJoin(对应到Spark源码中BroadcastNestedLoopJoinExec.scala)策略。 提起BroadcastNestedLoopJoin,不得不提Nested Loop Join,它在很多RDBMS中得到应用,比如mysql。它的工作方式是循环从一张表(ou...
expression[NOT] IN (sqlstatement) [NIET] EXISTS (sqlstatement) Een subquery bestaat uit deze onderdelen: Opmerkingen U kunt een subquery gebruiken in plaats van een expressie in de lijst met velden van een SELECT-instructie of in een WHERE- of HAVING-component. In een subquery gebruikt u ...
in => = any(...) i > all() => not(i <= any(...)) some => any 子查询几乎可以出现在 SQL 的任何位置,如 from/where/select/group by/having/order by, 外加关联子查询的存在,所以处理子查询变得具有挑战性,在深入子查询之前,先介绍一下 Databend 为了高效处理子查询 而引入的非标准 join ...
I am trying to write a query with a subquery. The subquery returns what is in the attached image below. select top(1) with ties matter_uno, PART_CAT_CODE, EFF_DATE, EMPL_UNO from TBM_CLMAT_PART where MATTER_UNO = 11275 and PART_CAT_CODE = 'BILL' order…
FROM employees WHERE SALARY > (SELECT DISTINCT SALARY FROM employees WHERE LAST_NAME = 'Bull'); #2 Write a query to find the names (first_name, last_name) of all employees who works in the IT department #2 编写查询以查找在IT部门工作的所有员工的名称(名,姓) ...
result FROM (SELECT column_name FROM table_name WHERE column_name IN (SELECT column_name FROM ...