Oracle中返回结果集的存储介绍
作者:[网上资料 ]
google了一篇不错的例子,加了点注解,这样看起来更方便了:)Oracle不像SQLServer那样在存储过程中用Select就可以返回结果集,而是通过Out型的参数进行结果集返回的。实际上是利用REF CURSOR--procedure返回记录集:----------------------声明一个Package-------------- CREATE OR REPLACE PACKAGE pkg_test AS TYPE myrctype IS REF CURSOR; PROCEDURE get (p_id NUMBER, p_rc OUT myrctype); --Package中声明名为get 的Procedure(只有接口没内容)END pkg_test;-------------------------------------------------------------------------声明Package Body,即上面Package中的内容,包括Procedure get--------------------- CREATE OR REPLACE PACKAGE BODY pkg_test AS PROCEDURE get (p_id NUMBER, p_rc OUT myrctype) IS sqlstr VARCHAR2 (500); BEGIN IF p_id = 0 THEN OPEN p_rc FOR SELECT ID, NAME, sex, address, postcode, birthday FROM student; ELSE sqlstr := 'select id,name,sex,address,postcode,birthday from student where id=:w_id'; --w_id是个参数,--以下 p_rc是个REF CURSOR游标类型,而且是OUT型参数,即可返回一个记录集了。USING p_id就是替换上面SQL中:w_id值拉:) OPEN p_rc FOR sqlstr USING p_id; END IF; END get; END pkg_test; --function返回记录集的例子,原理和上面相同,而是用function的return值来返回记录集。函数返回记录集: 建立带ref cursor定义的包和包体及函数: CREATE OR REPLACE package pkg_test as /* 定义ref cursor类型 不加return类型,为弱类型,允许动态sql查询, 否则为强类型,无法使用动态sql查询; */ type myrctype is ref cursor; function get(intID number) return myrctype; end pkg_test; /CREATE OR REPLACE package body pkg_test as --函数体 function get(intID number) return myrctype is rc myrctype; --定义ref cursor变量 sqlstr varchar2(500); begin if intID=0 then --静态测试,直接用select语句直接返回结果 open rc for select id,name,sex,address,postcode,birthday from student; else --动态sql赋值,用:w_id来申明该变量从外部获得 sqlstr := 'select id,name,sex,address,postcode,birthday from student where id=:w_id'; --动态测试,用sqlstr字符串返回结果,用using关键词传递参数 open rc for sqlstr using intid; end if;return rc; end get;end pkg_test;
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