上一篇解析链接如下: https://www.cnblogs.com/wcwen1990/p/9325968.html 1.SQL示例1: SQL> select * from ( select * from tmp1 where c >= 1 ) t1 left join ( select * from tmp2 where b < 30 ) t2 on t1.a = t2.a and t2.d > 1 and t1.e >= 2 where t1.b < 50 ;…
错误提示: psql: could not connect to server: No such file or directory Is the server running locally and accepting connections on Unix domain socket "/var/run/postgresql/.s.PGSQL.5432"? 出现该问题的很多,以下是目前碰到的几种情况,之后碰到继续补充: 1.删除了/tmp路径中的.s.PGSQL.5432 与.…