sql_分类_产笑科技

thinkphp5开启sql日志记录

thinkphp5开启sql日志记录的方法

阅读全文

posted @ 2022-11-24 21:15:46 阅读(1505)

mysql报错Expression #1 of SELECT list is not in GROUP BY clause and contains nonaggregated column问题解决

报错信息：Expression #1 of SELECT list is not in GROUP BY clause and contains nonaggregated column 'web_db.articles_tag.id' which is not functionally dependent on columns in GROUP BY clause; this is incompatible with sql_mode=only_full_group_by

阅读全文

posted @ 2022-05-04 16:43:27 阅读(744)

mysql报错Expression #2 of ORDER BY clause is not in GROUP BY clause and contains nonaggregated column问题解决

报错信息：Expression #2 of ORDER BY clause is not in GROUP BY clause and contains nonaggregated column 'web_db.articles_tag.id' which is not functionally dependent on columns in GROUP BY clause; this is incompatible with sql_mode=only_full_group_by

阅读全文

posted @ 2022-05-04 16:34:00 阅读(727)

mysql报错Expression #3 of SELECT list is not in GROUP BY clause and contains nonaggregated column问题

今天sql一对多关联查询发现一个错误，提示说查询的字段不在group by的子句中，因为sql_mode是only_full_group_by。

阅读全文

posted @ 2020-07-12 13:50:27 阅读(386)

sql查询：存在A表而不在B表中的数据

A、B两表，找出ID字段中，存在A表，但是不存在B表的数据。方法一：使用 not in

阅读全文

posted @ 2019-10-06 09:48:51 阅读(889)

sql update set使用case when语句

update TD_XXX set djyzmdm=null,djyzmsj=null,DLCS= case when DLCS is null then 1 else DLCS+1 end where djsj='xxx'

阅读全文

posted @ 2019-07-05 17:46:13 阅读(1316)

mysql表复制create table like和create table as比较

CREATE TABLE A LIKE B 此种方式在将表B复制到A时候会将表B完整的字段结构和索引复制到表A中来。

阅读全文

posted @ 2019-07-05 17:45:22 阅读(385)

mysql 中find_in_set()和in()用法比较

mysql 中find_in_set()和in()用法比较，在mysql中in可以包括指定的数字，而find_in_set()用于特定的数据类型。find_in_set 函数使用方法个例子来说：有个文章表里面有个type字段，它存储的是文章类型，有 1头条、2推荐、3热点、4图文...1,12,13 等等。

阅读全文

posted @ 2019-06-07 17:33:54 阅读(368)

MySQL: ON DUPLICATE KEY UPDATE 用法

使用该语法可在插入记录的时候先判断记录是否存在，如果不存在则插入，否则更新，很方便，无需执行两条SQL

阅读全文

posted @ 2019-04-30 19:48:42 阅读(283)