• 动态游标(比如表名作为參数)以及动态SQL分析


    表名作为參数的动态游标

    DECLARE
       v_table_name VARCHAR2(30) := 'CUX_MES_WIP_BARCODE_MAP';
       --l_rec        SYS_REFCURSOR;
       TYPE t_data IS TABLE OF VARCHAR2(30) INDEX BY BINARY_INTEGER;
       TYPE t_cur IS REF CURSOR;
       l_data       t_data;
       l_rec        t_cur;
       l_cur        VARCHAR2(4000);
       v_fm_barcode VARCHAR2(30) := 'cxy-p-001';
       v_to_barcode VARCHAR2(30) := 'cxy-p-002';
       v_barcode    VARCHAR2(30);
    BEGIN
    
       l_cur := 'select barcode from ' || v_table_name || ' where barcode >= ' ||
                ''''||v_fm_barcode||'''' || ' and barcode <= ' ||
                ''''||v_to_barcode || '''';
       dbms_output.put_line(l_cur);
       OPEN l_rec FOR l_cur;
       LOOP
          EXIT WHEN l_rec%NOTFOUND;
          FETCH l_rec BULK COLLECT
             INTO l_data;
          FOR i IN 1 .. l_data.count LOOP
          
             dbms_output.put_line(l_data(i));
          END LOOP;
       
       END LOOP;
    END;
    

    动态SQL

    /*
     1.什么是动态SQL?
     动态SQL是指在运行PL/SQL块时动态输入SQL语句。在PL/SQL块中仅仅能运行DDL(create、alter、drop)、DCL
     (grant、revoke)或比較灵活的SQL语句(如select子句不带where条件);
     动态SQL的性能不如静态SQL,可是比較灵活;
     在PL/SQL块中编写动态SQL语句时须要将SQL语句存放到字符串变量中并且SQL语句能够包括占位符(以冒号開始);
     
    
    2.动态SQL的语法
     2.1 使用execute immediate语句
     能够处理多数动态SQL操作如:DDL语句(create、alter、drop)、DML语句(insert、update、delete)、DCL(grant、revoke)
     以及单行的select子句。可是不能处理多行查询语句。

    2.2 使用open...for,fetch和close语句 在游标中使用。

    2.3 使用批量动态SQL语句 */ --------------------------------------------------------------- *************************************************************** 1. 使用execute immediate --------------------------------------------------------------- 1.1 使用execute immediate处理DDL语句 --------------------------------------------------------------- --案例01:使用execute immediate处理DDL语句--create declare create_table varchar2(200); begin create_table:='create table ' ||'&table_name' ||'(sid int, sno int)'; execute immediate create_table ; end; --案例02:使用execute immediate处理DDL语句---alter declare alter_table varchar2(200); begin alter_table:='alter table &target_table_name modify &column_name varchar2(10)'; execute immediate alter_table ; end; --案例03:使用execute immediate处理DDL语句---drop declare drop_table varchar2(200); begin drop_table:='drop table ' ||'&target_table_name'; execute immediate drop_table ; end; --案例04:使用execute immediate处理DDL语句--drop table create or replace procedure drop_table (table_name varchar2) is sql_sta varchar2(200); begin sql_sta:='drop table ' ||table_name; execute immediate sql_sta; end; --调用方法: exec drop_table('accp'); --案例05:使用execute immediate处理DDL语句--create+select declare select_sta varchar2(200); emp_rec emp%rowtype; begin execute immediate 'create table sodi(sid int, sno int)'; select_sta:='select * from emp where empno=:id'; execute immediate select_sta into emp_rec using &1; /*使用占位符时,这个占位符是在引號内使用的*/ end; --------------------------------------------------------- 1.2 使用execute immediate处理DCL语句 ---------------------------------------------------------- --案例01:使用execute immediate处理DCL语句--grant create or replace procedure grant_priv(priv varchar2, username varchar2) is priv_stat varchar2(200); begin priv_stat:=' grant '|| priv || ' to ' || username; --注意字符串和连接符之间的空格 execute immediate priv_stat; end; --调用方法 exec grant_priv('create session', 'scott'); --案例02:使用execute immediate处理DCL语句--revoke create or replace procedure revoke_priv(priv varchar2, username varchar2) is priv_stat varchar2(200); begin priv_stat:=' revoke '|| priv || ' from ' || username; --注意字符串和连接符之间的空格 execute immediate priv_stat; end; --调用方法 exec revoke_priv('create session', 'scott'); ---------------------------------------------------------------- 1.3.使用execute immediate处理DML语句 ---------------------------------------------------------------- 1.处理无占位符和return子句的DML语句 --案例01:查询子句:select declare sql_stat varchar2(100); begin sql_stat:='select * from emp'; execute immediate sql_stat; end; --案例02:处理无占位符和return子句的DML语句--insert declare insert_table varchar2(200); begin insert_table:='insert into &table_name values (&sid, &sno)'; execute immediate insert_table; end; --案例03:处理无占位符和return子句的DML语句--update declare update_table varchar2(200); begin update_table:='update &table_name set &column_name=&new_value '; execute immediate update_table; end; --案例06:处理无占位符和return子句的DML语句--delete declare delete_table varchar2(200); begin delete_table:='delete from &table_name '; execute immediate delete_table; end; --案例05:新建一个表然后插入数据--create+insert declare create_table varchar2(200); begin create_table:='create table &table_name(sid int, sno int)'; execute immediate create_table ; end; declare insert_table varchar2(200); begin insert_table:='insert into &table_name values (&sid, &sno)'; execute immediate insert_table; end; --案例06:同一时候实现新建一个表并插入数据--create+insert declare create_table varchar2(200); insert_table varchar2(200); begin create_table:='create table &table_name (sid int, sno int)'; execute immediate create_table ; insert_table:='insert into &table_name values (&sid, &sno)'; execute immediate insert_table; end; --案例07:同一时候实现新建一个表并插入数据--create+insert+update /* 这里也能够分开写 */ declare create_table varchar2(200); insert_table varchar2(200); update_table varchar2(200); begin create_table:='create table &table_name (sid int, sno int)'; execute immediate create_table ; insert_table:='insert into &table_name values (&sid, &sno)'; execute immediate insert_table; update_table:='update &table_name set &column_name=&new_value where sid=&old_value'; execute immediate update_table; end; --案例08:同一时候实现新建一个表并插入数据--create+insert+update+delete declare create_table varchar2(200); insert_table varchar2(200); update_table varchar2(200); delete_table varchar2(200); begin create_table:='create table &table_name (sid int, sno int)'; execute immediate create_table ; insert_table:='insert into &table_name values (&sid, &sno)'; execute immediate insert_table; update_table:='update &table_name set &column_name=&new_value where sid=&old_value'; execute immediate update_table; delete_table:='delete from &delete_tablename'; execute immediate delete_table; end; --案例08:同一时候实现新建一个表并插入数据--create+insert+update+delete+insert declare create_table varchar2(200); insert_table varchar2(200); update_table varchar2(200); delete_table varchar2(200); re_insert_table varchar2(200); begin create_table:='create table &table_name (sid int, sno int)'; execute immediate create_table ; insert_table:='insert into &table_name values (&sid, &sno)'; execute immediate insert_table; update_table:='update &table_name set &column_name=&new_value where sid=&old_value'; execute immediate update_table; delete_table:='delete from &delete_tablename'; execute immediate delete_table; re_insert_table:='insert into &re_table_name values (&new_sid, &new_sno)'; execute immediate re_insert_table; end; 2.处理占位符的DML语句 --案例01:处理占位符的DML语句:create+insert declare create_table varchar2(200); insert_table varchar2(200); begin create_table:='create table &table_name (sid int, sno int)'; execute immediate create_table ; insert_table:='insert into &target_table_name values (:sid, :sno)'; execute immediate insert_table using &2,&3; end; --案例02:处理占位符的DML语句:create+insert_update declare create_table varchar2(200); insert_table varchar2(200); update_table varchar2(200); begin create_table:='create table &table_name (sid int, sno int)'; execute immediate create_table ; insert_table:='insert into &target_table_name values (:sid, :sno)'; execute immediate insert_table using &1,&2; update_table:='update &update_tablename set &update_column_name=:new_value where &condition_column=:old_value '; execute immediate update_table using &3 ,&4; end; ---or declare create_table varchar2(200); insert_table varchar2(200); update_table varchar2(200); begin create_table:='create table &新建的表名 (sid int, sno int)'; execute immediate create_table ; insert_table:='insert into &插入数据的表名 values (:sid, :sno)'; execute immediate insert_table using &sid的值 ,&sno的值; update_table:='update &被更新的表名 set &更新的列名=:new_value where &条件列=:old_value '; execute immediate update_table using &新值 ,&条件列的值; end; --案例03:处理占位符的DML语句:create+update+insert+delete declare create_table varchar2(200); insert_table varchar2(200); update_table varchar2(200); delete_table varchar2(200); begin create_table:='create table &table_name (sid int, sno int)'; execute immediate create_table ; insert_table:='insert into &target_table_name values (:sid, :sno)'; execute immediate insert_table using &1,&2; update_table:='update &update_tablename set &update_column_name=:new_value where &update_condition_column=:delete_condition_column_value '; execute immediate update_table using &3 ,&4; delete_table:='delete from &dele_table_name where &delete_condition_column=:delete_condition_column_value'; execute immediate delete_table using &5; end; ---运行过程: SQL> declare 2 create_table varchar2(200); 3 insert_table varchar2(200); 4 update_table varchar2(200); 5 delete_table varchar2(200); 6 begin 7 create_table:='create table &table_name (sid int, sno int)'; 8 execute immediate create_table ; 9 10 insert_table:='insert into &target_table_name values (:sid, :sno)'; 11 execute immediate insert_table using &1,&2; 12 13 update_table:='update &update_tablename set &update_column_name=:new_value where &update_condition_column=:delete_condition_column_value '; 14 execute immediate update_table using &3 ,&4; 15 16 delete_table:='delete from &dele_table_name where &delete_condition_column= :delete_condition_column_value'; 17 execute immediate delete_table using &5; 18 end; 19 / 输入 table_name 的值: sz 原值 7: create_table:='create table &table_name (sid int, sno int)'; 新值 7: create_table:='create table sz (sid int, sno int)'; 输入 target_table_name 的值: sz 原值 10: insert_table:='insert into &target_table_name values (:sid, :sno)'; 新值 10: insert_table:='insert into sz values (:sid, :sno)'; 输入 1 的值: 101 输入 2 的值: 201 原值 11: execute immediate insert_table using &1,&2; 新值 11: execute immediate insert_table using 101,201; 输入 update_tablename 的值: sz 输入 update_column_name 的值: sid 输入 update_condition_column 的值: sno 原值 13: update_table:='update &update_tablename set &update_column_name=:new_ value where &update_condition_column=:delete_condition_column_value '; 新值 13: update_table:='update sz set sid=:new_value where sno=:delete_conditi on_column_value '; 输入 3 的值: 1001 输入 4 的值: 201 原值 14: execute immediate update_table using &3 ,&4; 新值 14: execute immediate update_table using 1001 ,201; 输入 dele_table_name 的值: sz 输入 delete_condition_column 的值: sno 原值 16: delete_table:='delete from &dele_table_name where &delete_condition_c olumn=:delete_condition_column_value'; 新值 16: delete_table:='delete from sz where sno=:delete_condition_column_valu e'; 输入 5 的值: 201 原值 17: execute immediate delete_table using &5; 新值 17: execute immediate delete_table using 201; PL/SQL 过程已成功完毕。 SQL> select * from sz; 未选定行 3.处理包括returning子句的DML语句 --案例01:处理包括returning子句的DML语句--create+insert+update declare create_table varchar2(200); insert_table varchar2(200); update_table varchar2(200); res varchar2(100); begin create_table:='create table &new_table_name (sid int, sno int)'; execute immediate create_table; insert_table:='insert into &insert_target_table_name values (:sid, :sno)'; execute immediate insert_table using &1,&2 ; update_table:='update &update_target_table_name set &udpate_column_name=:new_value where &condition_column_name=:old_value returning &returning_name into :res'; execute immediate update_table using &3,&4 returning into res; dbms_output.put_line('the result is : ' ||res); end;






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  • 原文地址:https://www.cnblogs.com/blfbuaa/p/6951305.html
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