我正在使用Oracle10g,试图排除在Oracle10g的字符类中包含-或带插入符号的_的条目。我可以通过以下命令找到包含破折号或下划线的条目:
WITH example
AS (SELECT 'AAAA-1' n FROM DUAL
UNION
SELECT 'AAAAA_1' FROM DUAL
UNION
SELECT 'AAAA' FROM DUAL)
SELECT *
FROM example
WHERE REGEXP_LIKE (n, '
有两个select语句:
select max(min(str)) from (select 0 id, 'a' str from dual) group by id having min(str) = 'a';
select strconcat(min(str)) from (select 0 id, 'a' str from dual) group by id having min(str) = 'a';
唯一的区别是外层聚合函数:max()与strconcat()。
您可以将strconcat()替换为您已有的任