摘要：From Wikipedia, the free encyclopedia For cross-tabulation that aggregates only by counting (rather than summing, averaging, etc.), see Contingency ta 阅读全文

摘要：If the object being deleted has incomplete class type at the point of deletion and the complete class has a non-trivial destructor or a deallocation f 阅读全文

摘要：1、安装 sudo apt install postgresql-all 2、建立用户 sudo su - postgres，可以免密登录数据库create user myuser with password '111' CREATEDB;用新用户登录，不出意外应该会报Peer authentica 阅读全文