POSTGRESQL 别名 技术教程文章

postgresql 大小写,别名

ask.id "id",ask.createTime "createTime",ask.publisherID "publisherID",users.nickname "nickname", users.icon "icon",users.gender "gender",ask.reward "reward",ask.zan "zan",ask.commentID "commentID", ask.typee "type",ask.label "label",ask.content "content",ask.image "image",count(comment.id) "commentCount" from ask inner join users on ask.publisherID=users.id left outer join comment on comment.obje...

PostgreSQL-9-别名与动态表复制

1、列别名 SELECT column_name AS alias_name FROM table_name conditions... ; alias_name: 它指定分配给列的临时名称 SELECT name,MAX(salary) AS salary_max FROM company3 GROUP BY name; 将salary的最大值设置为别名salary_max SELECT age,classno,studentname AS n FROM student; 将studentname设置为别名n 2、表别名 SELECT column1, column2.... FROM table_name AS alias_name conditions....; alias_name:它指...