RegexBuddy is your perfect companion for working with regular expressions. Learning, creating, understanding, testing, using and saving regular expressions has never been easier....
文章浏览阅读872次。SQL---Expression #1 of ORDER BY clause is not in GROUP BY clause and contains nonaggregated column '数据库中执行sql语句时报这个错误: Expression #1 of ORDER BY clause is not in GROUP BY clause and contains nona..._sqlsugar expression #1 of order by clause is......
文章浏览阅读6.4k次。最近遇到了一个宏:#define crReturn(z) /do {/crLine=__LINE__; return (z); case__LINE__:;/} while (0)用VS2003编译的时候,提示 error C2051: case expression not constant按照宏替换的道理,__LINE应该是会换成行号,是整数常量啊,没有......
文章浏览阅读6.4k次。最近遇到了一个宏:#define crReturn(z) /do {/crLine=__LINE__; return (z); case__LINE__:;/} while (0)用VS2003编译的时候,提示 error C2051: case expression not constant按照宏替换的道理,__LINE应该是会换成行号,是整数常量啊,没有......
对于GROUP BY聚合操作,如果在SELECT中的列,没有在GROUP BY中出现,那么将认为这个SQL是不合法的,因为列不在GROUP BY从句中因为有only_full_group_by,所以我们要在MySQL中正确的使用group by语句的话,只能是select column1 from tb1 group by colum......