【正文】 ............................................................................................8 、基本概念：...................................................................................................................................8 、數(shù)據(jù)庫安全：...............................................................................................................................8 、基本的SQL SELECT 語句.............................................................................................................8 、SELECT語句...................................................................................................................................9 語法：.......................................................................................................................................9 SQL語句說明：.................................................... .....................................................................9 數(shù)字和日期都可以使用數(shù)學運算符建立表達式。...............................................................9 定義空（NULL）值...................................................................................................................9 別名...........................................................................................................................................9 spool +路徑 ...........................................................................................................................10 連接操作符： || ...................................................................................................................10 文本字符串.............................................................................................................................10 DISTINCT......................................................................... ........................................................10 、SQLPLUS 與 SQL 的關系...........................................................................................................10 SQLPLUS命令的功能：...........................................................................................................10 查詢 SQLPLUS 命令...............................................................................................................10 SQLPLUSW 在 WINDOWS 下運行的分析器。.................................................................................................................................................29 2.amp。...............................................................................................................................................29 ：...................................................................................................................................29 格式化命令：................................................................................................................................30 做腳本文件的過程：......................................................................... ...........................................31 數(shù)據(jù)操作語句：............................................................................................................................31 1. 插入...................................................................................................................................31 2. 刪除...................................................................................................................................31 3. 更新...................................................................................................................................31 4. MERGE語句.........................................................................................................................32 5. 事務（transaction）：...................................................................................................32 創(chuàng)建和管理表................................................................................................... .............................33 表（TABLE）基本的存儲單位，由行和列組成。.............................................................................34 CTAS（子查詢建表）：...........................................................................................................34 截取：.....................................................................................................................................35 給表加注釋：COMMENT...........................................................................................................36 約束條件：.............................................................................................................................36 （VIEW）........................................................................................................................... ..37 、序列：.........................................................................................................................................39 、索引：.........................................................................................................................................40 控制用戶的訪問............................................................................................................................41 .......................................................................................................................41 ：.......................................................................................................................................41 ...........................................................................................................................42 BY 子句：.......................................................................................... ...........................42 BY 子句的增強.............................................................................................................43 函數(shù).........................................................................................................................43 高級子查詢...............................................................................