Shulou(Shulou.com)06/01 Report--

The With query statement begins with with, which is equivalent to building a temporary table before the query, and the specified query results are stored in the temporary table, and then it can be used many times for further analysis and processing.

Syntax:

With _ tempTable as (select * from table) select * from _ tempTable

Example:

With _ tempStudent as (select * from t_student t where class = 'Class 3, Grade 8') select sex,count (1) nums from _ tempStudent where sex = 'male' and height > '170'union allselect sex,count (1) nums from _ tempStudent where sex =' female 'and height >' 160'

Multiple with as uses each temporary stock is directly separated by ","

With T1 as (select * from student where name in ('Zhang San','Li Si'), T2 as (select * from student where name in ('Wang Wu') select * from t1union select * from T2

If the with as is nested and there are multiple with as, the temporary object declared first can be called directly within the following as.

With T1 as (select * from student where name in ('Zhang San','Li Si'), T2 as (select * from T1 where name in ('Wang Wu')) select * from T2

Welcome to subscribe "Shulou Technology Information " to get latest news, interesting things and hot topics in the IT industry, and controls the hottest and latest Internet news, technology news and IT industry trends.