标签：select
求帮助入职写数据库查询语句遇到问题，求大神们帮忙！
是这样的，现在有T1,T2,T3,T4 T5 5张表，以T1为主表，多表联查数据。 本人是这样写的： (SELECT T1.CODE, T2.NAME,T3.TYPE,T4.ACCOUNT FROM T1 INNER JOIN T2 ON T1.ID=T2.ID INNER JOIN T3 ON T1.ID=T3.ID INNER JOIN T4 ON T1……
没有数量栏，只有由count（）求数量，查询能出来正确结果，怎么样行转列？
没有行转列的正确SQL： select d.Region,d.MODEL,count(d.WLAN_MAC) as “数量” from deviceinfo as d GROUP BY d.Region,d.MODEL; 本人本人写的的行转列，格式正确，但是数量错误： select d.region, count(if(d.MOD……
MYSQL:SELECT * FROM (SELECT * FROM USER ORDER BY USER_N
在mysql中执行如SELECT * FROM (SELECT * FROM USER ORDER BY USER_NAME) TMP LIMIT 0 20这种语句，最终结果为什么没有安装user_name排序？ 解决方案 10 查询子集中的排序是不起作用的吧。 SELECT * FROM USER ORDER BY USER_NAME LIMIT 0 20……
问一下带in 和 子查询的sql语句怎么进行优化？
UPDATE user_bank_info set fisused = 2 where fuserid in ( SELECT userid FROM ( select DISTINCT ubi.fuserid as userid from customer as c JOIN user_bank_info as ubi ON c.fuserid =ubi……
timestamp的问题
问下select UNIX_TIMESTAMP(select lendtime from lendlist where lid = 19);为什么会报错？ 该怎么解决？ 解决方案 10 试试：SELECT UNIX_TIMESTAMP(SELECT lendtime FROM lendlist WHERE lid=19); 呢，怀疑你的是(不规范导致的……
哪个帮本人优化下这个sql语句，跪谢了……
SELECT t.* FROM (SELECT t1.USER_ID,t3.CUST_ID,t3.BILL_ID AS MSISDN,t3.CREATE_DATE AS ACTIVE_DATE,t1.ACCT_ID,t2.CUST_GROUP FROM so1.ins_accrel_571 t1,so1.um_cm_account t2 ,so1.ins_u……
mysql 多表连接语句优化讨教
SELECT * from (SELECT `dili_c`.*, `dili_uf`.`fchannelcode`,`dili_uf`.`fcashbalance`, `dili_uf`.`fchannelbalance`, `dili_uf`.`favailablebalance`, `dili_uf`.`fholdbalance`, (SELECT……