摘要: students class teacher_id student math_grade chinese_grade sex 1 t1 n1 60 80 女 2 t2 n2 50 90 男 3 t1 n3 80 30 男 1、group by 和 having 函数的应用 select max(ms 阅读全文
posted @ 2024-03-04 17:20 清风徐徐~~ 阅读(29) 评论(0) 推荐(0)
摘要: SET @start_date = '2023-11-17'; SET @end_date = '2023-11-20'; select a.city,b.t2-a.t1 from (select city,wework_gft_group_user_cnt t1 from fc_sr_day_we 阅读全文
posted @ 2023-11-21 12:10 清风徐徐~~ 阅读(74) 评论(0) 推荐(0)
摘要: select replace(d_day,'-','' ) from fc_sr_day_sale_ad_order; 语法 REPLACE ( ''string_replace1'' , ''string_replace2'' , ''string_replace3'' ) 参数 ''string 阅读全文
posted @ 2023-08-22 15:17 清风徐徐~~ 阅读(50) 评论(0) 推荐(0)
摘要: #sao.finished_at is null select sao.id,sao.finished_at from miniapp.fc_sale_ad_orders sao where case when sao.finished_at='' then( case when sao.finis 阅读全文
posted @ 2023-04-17 13:27 清风徐徐~~ 阅读(56) 评论(0) 推荐(0)
摘要: 首先,先熟悉书写SQL查询语句的优先顺序:(1) SELECT(2) FROM(3) WHERE(4) GROUP BY(5) HAVING(6) ORDER BY(7) LIMIT 开始~~~~~~~1.创建数据库CREATE DATABASE prc 2.创建表tb_name,tb_stu下面是 阅读全文
posted @ 2021-06-08 17:22 清风徐徐~~ 阅读(199) 评论(0) 推荐(0)