码迷,mamicode.com
首页 >  
搜索关键字:where    ( 20257个结果
错误代码: 1247 Reference 'startTime' not supported (forward reference in item list)
1、错误描述1 queries executed, 0 success, 1 errors, 0 warnings 查询:SELECT a.createUserId AS typeId, (SELECT COUNT(c.id) FROM t_aps c WHERE c.`status` IN (2, 5) AND c.createTime >= start... 错误代码: 1247 Refe...
分类:其他好文   时间:2015-07-21 20:42:40    阅读次数:832
错误代码: 1054 Unknown column 't.createUsrId' in 'group statement'
1、错误描述1 queries executed, 0 success, 1 errors, 0 warnings 查询:select count(t.id),t.`createUserId` from t_acs_ints t where t.id not in (SELECT t1.ionId FROM t_acs_cont t1, t_ac... 错误代码: 1054 Unknown c...
分类:其他好文   时间:2015-07-21 20:41:58    阅读次数:206
子查询与连接
子查询(Subquery)是指出现在其他SQL语句内的SELECT子句例如:SELECT * FROM t1 WHERE col1 = (SELECT col2 FROM t2);其中SELECT * FROM t1,称为Outer Query/Outer Statement(外层查询)SELECT...
分类:其他好文   时间:2015-07-21 20:16:46    阅读次数:103
海量数据查询代码优化--转载
具体要注意的:1.应尽量避免在 where 子句中对字段进行 null 值判断,否则将导致引擎放弃使用索引而进行全表扫描,如:select id from t where num is null可以在num上设置默认值0,确保表中num列没有null值,然后这样查询:select id from t...
分类:其他好文   时间:2015-07-21 20:11:37    阅读次数:107
UPDATE
1 --使用表达式更新一个单列的值 2 UPDATE employee 3 SET salary = salary*1.1 4 WHERE department_id = 90 5 6 --使用子查询更新一个单列的值 7 UPDATE employee 8 SET salary ...
分类:其他好文   时间:2015-07-21 18:37:07    阅读次数:93
DELETE
1 DELETE FROM table1 WHERE ...
分类:其他好文   时间:2015-07-21 18:33:52    阅读次数:64
Sql去重复查询
select *from ( select *, row_number() over (partition by Code order by code desc ) as seq from GNS_Goods ) as t where seq=1
分类:数据库   时间:2015-07-21 14:39:35    阅读次数:200
LeetCode 1 Two Sum
1Given an arrayof integers, find two numbers such that they add up to a specific targetnumber.The functiontwoSum should return indices of the two numbers such that they add up to thetarget, where inde...
分类:其他好文   时间:2015-07-21 12:56:09    阅读次数:93
[LeetCode][Java] Path Sum II
题目: Given a binary tree and a sum, find all root-to-leaf paths where each path's sum equals the given sum. For example: Given the below binary tree and sum = 22, 5 /...
分类:编程语言   时间:2015-07-21 12:54:55    阅读次数:127
SQL与NoSQL的CRUD对比
SQL与NoSQL的CRUD对比 flyfish 2015-7-21 Create, Read, Update and Delete (CRUD) SQL方式 查 SELECT 列名称 FROM 表名称 SELECT * FROM 表名称 SELECT 列名称 FROM 表名称 WHERE 列 运算符 值 增 INSERT...
分类:数据库   时间:2015-07-21 12:49:55    阅读次数:134
© 2014 mamicode.com 版权所有  联系我们:gaon5@hotmail.com
迷上了代码!