Warning: Attempt to read property "ID" on bool in /www/wwwroot/129.28.78.18/wp-content/themes/storeys-pro/wbc/components/og_schema/wb_og_schema.php on line 471

Warning: Attempt to read property "display_name" on bool in /www/wwwroot/129.28.78.18/wp-content/themes/storeys-pro/wbc/components/og_schema/wb_og_schema.php on line 480

Warning: Attempt to read property "display_name" on bool in /www/wwwroot/129.28.78.18/wp-content/themes/storeys-pro/wbc/components/og_schema/wb_og_schema.php on line 487

Warning: Attempt to read property "description" on bool in /www/wwwroot/129.28.78.18/wp-content/themes/storeys-pro/wbc/components/og_schema/wb_og_schema.php on line 489

Warning: Attempt to read property "ID" on bool in /www/wwwroot/129.28.78.18/wp-content/themes/storeys-pro/wbc/components/og_schema/wb_og_schema.php on line 493

2020.09.23.叶梦宇

学习总结

外键约束

多表联查:通过主键的id的值找到另一张表的id数据

先创建,没有外键的表

删除时,先删除有外键的表

模糊查询

条件是在where 关键词后面写

like 一种好像的意思

_只表示一位字符

%表示有0~n个字符

准备工作

GitHub、码云,git

准备自己 设计 “个人博客的数据库”

node

微信小程序:云数据库(mongodb)

nosql(json)

学习心得

使用数据库的时候疯狂报错,对数据库的操作不熟悉,虽然只学习了简单的数据库语句,但是还是会出现各种问题。对数据库还不熟练 ,还是要 多练习

评论留言