Richard.FreeBSD

摘要： 当在Linux下频繁存取文件后，物理内存会很快被用光，当程序结束后，内存不会被正常释放，而是一直作为caching。这个问题，貌似有不少人在问，不过都没有看到有什么很好解决的办法。那么我来谈谈这个问题。一、通常情况先来说说free命令：引用［root@server ~］# free -mtotal used free shared buffers cachedMem： 249 163 86 0 10 94-/+ buffers/cache： 58 191Swap： 511 0 511其中：引用total 内存总数used 已经使用的内存数free 空闲的内存数shared 多个进程共享的内存总 阅读全文

摘要： -- general notes:-- - tables are split using the protocol-- - keys are created outside the table, when possible-- - foreign keys (constraints) are added using ULOG2_ADD_FOREIGN_KEYS()-- - some procedures for maintainance are provided (suppressing entries, compressing tables, running ~VACUUM)-- - sec 阅读全文

摘要： CREATE TABLE log (log_id int(10) unsigned NOT NULL auto_increment,log_time datetime NOT NULL,log_user Varchar(30) NOT NULL,log_title Varchar(30) default NULL,log_content text default NULL,PRIMARY KEY(log_id)); 阅读全文

摘要： Oracle PL/SQL:CREATE TABLE statement: create a table with primary key.CREATE TABLE statement can be used to create table objects in database. It is possible to add constraints like primary key ,foreign key while table creation.Primary key is the unique identifier for a row of data.One table cannot c 阅读全文