1.利用group by 去重复2.可以利用下面的sql去重复,如下 1) select id,name,sex from (select a.*,row_number() over(partition by a.id,a.set order by name) su from test a ) where su=1 2)select id,name,sex from (select a.*,row_number() over(p
以下SQL执行时间按序号递减。1,动态SQL,没有绑定变量,每次执行都做硬解析操作,占用较大的共享池空间,若共享池空间不足,会导致其他SQL语句的解析信息被挤出共享池。create or replace procedure proc1as beginfor i in 1..100000 loop execute imme
case when 用法(1)简单case函数:格式: case 列名 when 条件值1 then 选项1 when 条件值1 then 选项2...... else 默认值 end例如: select case job_level when '1' then '1111' when '2' then '2222' when '3' then '3333
用到GROUP BY 语句查询时com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: Expression #2 of SELECT list is not in GROUP BY clause and contains nonaggregated column 'col_user_6.a.START_TIME' which is not functionally dependent on colu
触发器编号类别ORACLEMYSQL注释1创建触发器语句不同create or replace trigger TG_ES_FAC_UNIT before insert or update or delete on ES_FAC_UNIT for each rowcreate trigger `hs_esbs`.`TG_INSERT_ES_FAC_UNIT` BEFORE INSERT on `hs_esbs`.`es_fac_u
1.查询:注册时间为今天的所有用户数:select count(*) from customer where TO_DAYS(createtime) = TO_DAYS(NOW())2.获取当前时间到凌晨24点还有多长时间:(Java中可用于判断某时间是否为今天)final Calendar cal = Calendar.getInstance(); ca
Expression #1 of ORDER BY clause is not in GROUP BY clause and contains nonaggregated column 'information_schema.PROFILING.SEQ' which is not functionally dependent on columns in GROUP BY clause; this is incompatible with sql_mode=only_full_
Oracle sql 子字符串长度判断 select t.* from d_table t WHEREsubstr(t.col,1,1)='8' and instr(t.col,'/')0 and length(substr(t.col,1,instr(t.col,'/')))5; 字符串的前两位都是数字:select * from d_table t WHERE regexp_like(substr(t.col,1,2), '^[
DELETE FROM 表名 WHERE (字段1,字段2,字段3)IN (SELECT 字段1,字段2,字段3 FROM (SELECT 字段1,字段2,字段3 FROM 表名 GROUP BY 字段1,字段2,字段3 HAVING COUNT(*)1) s1) ANDid NOT IN (SELECT id FROM (SELECT id FROM 表名 GROUP BY 字段1,字段2,字段3