不久之后，我看到太多的怪人评论Oracle的问题，说“不要使用()运算符，而是使用JOIN语法”。
我确实看到这两个都很好。但是，使用它们的真正区别是什么？我会欢迎答案，更多来自经验。
1. Is there anything to do with limitations in application,performance,etc. while using them? 2. What would you suggest for me?
我在Oracle documentation读了一些东西，但并不足以让我理解或感受到全面的信息。
注意：我打算迁移200个包和程序，如果使用Keyword而不是()
3. Also is there any freeware tools to do the rewrite?
发布样品
+----------------------------------+------------------------------------------------+ |-INNER JOIN - CONVENTIONAL |-INNER JOIN - ANSI Syntax | |----------------------------------|------------------------------------------------| |SELECT |SELECT | | EMP.DEPTNO | ENAME,| |FROM | DNAME,| | EMP,| EMP.DEPTNO,| | DEPT | DEPT.DEPTNO | |WHERE | FROM | | EMP.DEPTNO = DEPT.DEPTNO; | SCOTT.EMP INNER JOIN SCOTT.DEPT | | | ON EMP.DEPTNO = DEPT.DEPTNO; | |----------------------------------|------------------------------------------------| |-LEFT OUTER JOIN - CONVENTIONAL |-LEFT OUTER JOIN - ANSI Syntax | |----------------------------------|------------------------------------------------| |SELECT | SELECT | | EMP.DEPTNO | ENAME,| | DEPT | DEPT.DEPTNO | |WHERE | FROM | | EMP.DEPTNO = DEPT.DEPTNO(+);| SCOTT.EMP LEFT OUTER JOIN SCOTT.DEPT | | | ON EMP.DEPTNO = DEPT.DEPTNO; | |----------------------------------|------------------------------------------------| |-RIGHT OUTER JOIN - CONVENTIONAL |-RIGHT OUTER JOIN - ANSI Syntax | |----------------------------------|------------------------------------------------| |SELECT | SELECT | | EMP.DEPTNO | ENAME,| | DEPT | DEPT.DEPTNO | |WHERE | FROM | | EMP.DEPTNO(+) = DEPT.DEPTNO;| SCOTT.EMP RIGHT OUTER JOIN SCOTT.DEPT | | | ON EMP.DEPTNO = DEPT.DEPTNO; | |----------------------------------|------------------------------------------------| |-FULL OUTER JOIN - CONVENTIONAL |-FULL OUTER JOIN - ANSI Syntax | |----------------------------------|------------------------------------------------| | | | |SELECT | SELECT | | * | * | |FROM | FROM | | EMP,| SCOTT.EMP FULL OUTER JOIN SCOTT.DEPT | | DEPT | ON EMP.DEPTNO = DEPT.DEPTNO; | |WHERE | | | EMP.DEPTNO = DEPT.DEPTNO(+) | | |UNION ALL | | |SELECT | | | * | | |FROM | | | EMP,| | | DEPT | | |WHERE | | | EMP.DEPTNO(+) = DEPT.DEPTNO | | | AND EMP.DEPTNO IS NULL; | | |__________________________________|________________________________________________|
PS：阅读所有更新分组的答案摘要。
