11.26 MySQL学习记录
摘要：
select * from world.country; select *from world.city; select *from world.countrylanguage; /*分组与排序*/select continent, count(*) as num_countryfrom world 阅读全文
posted @ 2017-11-26 16:29 vincenthe1 阅读(87) 评论(0) 推荐(0)
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