1118-02补充 cursor 基本例子

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fsmgmt.msc

/*
cursor
1.参数列表，is <select_statement> 是否含有 变量
2.接收游标值
2.1 标量类型变量
2.2 记录类型变量
2.3 for循环中的循环计数变量
3.游标属性
3.1 显式游标，ref cursor 语法: 游标名%游标属性
3.2 隐式游标 语法: SQL%游标属性
*/

set serveroutput on;
/*cursor,无参，接收游标值:1.标量类型变量*/
declare
cursor v_cur is
select serial_no,type_code,brand_code,brand_name from t_sales;
vi_serial_no integer;
vv_type_code varchar2(30);
vv_brand_code varchar2(30);
vv_brand_name varchar2(30);
begin
open v_cur;
loop
fetch v_cur into vi_serial_no,vv_type_code,vv_brand_code,vv_brand_name;
exit when v_cur%notfount;
dbms_output.put_line( vi_serial_no||','||vv_type_code||','||vv_brand_code||','||vv_brand_name );
end loop;
close v_cur;
exception
dbms_output.put_line(sqlcode||sqlerrm);
end;
/

set serveroutput on;
/*cursor,无参，接收游标值:2.记录类型变量*/
declare
cursor v_cur is
select serial_no,type_code,brand_code,brand_name from t_sales;
type t_record is record (
serial_no integer,
type_code varchar2(30),
brand_code varchar2(30),
brand_name varchar2(30)
);
v_record t_record; --记录类型 的显式定义
--v_record t_sales%rowtype; --记录类型 的隐式定义（table）
-- v_record v_t_sales%rowtype; --记录类型 的隐式定义（view）
--v_record v_cur%rowtype; --记录类型 的游标定义
begin
open v_cur;
loop
fetch v_cur into v_record;
-- fetch v_cur into v_record.serial_no,v_record.type_code,v_record.brand_code,v_record.brand_name;
exit when v_cur%notfount;
dbms_output.put_line( vi_serial_no||','||vv_type_code||','||vv_brand_code||','||vv_brand_name );
end loop;
close v_cur;
exception
dbms_output.put_line(sqlcode||sqlerrm);
end;
/

set serveroutput on;
/*cursor,无参，接收游标值:3.for循环中的循环计数标量*/
declare
cursor v_cur is
select serial_no,type_code,brand_code,brand_name from t_sales;
begin
for i_row in v_cur loop
dbms_output.put_line( i_row.serial_no||','||i_row.type_code||','||i_row.brand_code||','||i_row.brand_name );
end loop;
exception
dbms_output.put_line(sqlcode||sqlerrm);
end;
/

set serveroutput on;
/*cursor，有参，无变量*/
declare
cursor v_cur(vp_serial_no integer default 5) is
select serial_no,type_code,brand_code,brand_name from t_sales where serial_no <= vp_serial_no;
begin
for i_row in v_cur(3) loop
dbms_output.put_line( i_row.serial_no||','||i_row.type_code||','||i_row.brand_code||','||i_row.brand_name );
end loop;
exception
dbms_output.put_line(sqlcode||sqlerrm);
end;
/

set serveroutput on;
/*cursor，有参，有变量*/
declare
vv_type_code varchar2(30);
cursor v_cur(vp_serial_no integer default 5) is
select serial_no,type_code,brand_code,brand_name from t_sales where serial_no <= vp_serial_no and type_code = upper(vv_type_code);
v_record v_cur%rowtype;
begin
vv_type_code := 'T01'; --open前 赋值
--open v_cur; --参数列表 有默认值的游标，open时可以不带参数列表
open v_cur(3);
loop
fetch v_cur into v_record;
exit when v_cur%notfount;
dbms_output.put_line( v_record.serial_no||','||v_record.type_code||','||v_record.brand_code||','||v_record.brand_name );
end loop;
close v_cur;
exception
dbms_output.put_line(sqlcode||sqlerrm);
end;
/

set serveroutput on;
/*游标属性:1.显式游标，ref cusor*/
declare
cursor v_cur is
select serial_no,type_code,brand_code,brand_name from t_sales;
v_record v_cur%rowtype;
begin
if not (v_cur%isopen) then
open v_cur;
end if;

fetch v_cur into v_record;
while v_cur%found loop
dbms_output.put_line( v_cur%rowcount||':'||v_record.serial_no||','||v_record.type_code||','||v_record.brand_code||','||v_record.brand_name );
fetch v_cur into v_record;
end loop;
exception
dbms_output.put_line(sqlcode||sqlerrm);
end;
/

set serveroutput on;
/*游标属性: 2.隐式游标*/
declare
type t_record is record (
serial_no integer,
type_code varchar2(30),
brand_code varchar2(30),
brand_name varchar2(30)
);
v_record t_record;
begin
select serial_no,type_code,brand_code,brand_name into v_record from t_sales where serial_no = 1;
dbms_output.put_line(to_char(SQL%rowcount));
update t_sales set brand_name = brand_name||'_01';
dbms_output.put_line(to_char(SQL%rowcount));
--commit;
rollback;
dbms_output.put_line(to_char(SQL%rowcount));
exception
dbms_output.put_line(sqlcode||sqlerrm);
end;
/

/* ref cursor
定义:
1.select语句
2.sql字符串
*/
set serveroutput on;
/*ref cursor,指定游标语句:1.select语句*/
declare
type t_ref_cursor is ref cursor;
v_ref_cur t_ref_cursor;
vi_serial_no integer := 5;
v_record t_sales%rowtype;
begin
open v_ref_cur for
select serial_no,type_code,brand_code,brand_name into v_record from t_sales where serial_no <= vi_serial_no;
loop
fetch v_ref_cur into v_record;
exit when v_reg_cur%notfound;
dbms_output.put_line(v_record.serial_no||','||v_record.type_code||','||v_record.brand_code||','||v_record.brand_name );
end loop;
exception
dbms_output.put_line(sqlcode||sqlerrm);
end;
/

set serveroutput on;
/*ref cursor,指定游标语句:2.sql字符串*/
declare
type t_ref_cursor is ref cursor;
v_ref_cur t_ref_cursor;
vi_serial_no integer := 5;
v_record t_sales%rowtype;
vv_sql varchar2(500);
begin
vi_serial_no := 3;
/*使用 普通变量
vv_sql := ' select serial_no,type_code,brand_code,brand_name into v_record from t_sales where serial_no <= '||vi_serial_no ;
open v_ref_cur for vv_sql;
*/
/*使用 绑定变量*/
vv_sql := ' select serial_no,type_code,brand_code,brand_name into v_record from t_sales where serial_no <= :serial_no' ;
open v_ref_cur for vv_sql using vi_serial_no; --open时指定绑定变量的值
loop
fetch v_ref_cur into v_record;
exit when v_reg_cur%notfound;
dbms_output.put_line(v_record.serial_no||','||v_record.type_code||','||v_record.brand_code||','||v_record.brand_name );
end loop;
exception
dbms_output.put_line(sqlcode||sqlerrm);
end;
/