至于return和exit在oracle存储过程中的应用,有些新手朋友们还是比较容易混淆的,本文将针对这两个关键字进行详细对比下,感兴趣的你可以参考下,希望可以帮助到你
代码如下:create or replace procedure Test5(o_cellphone in varchar2) is
v_cellphone cc_quiz_stat.cellphone %type;
v_name cc_quiz_stat %rowtype;
v_state cc_quiz_stat.state %type;
begin
declare
cursor cur_cc is
select * from cc_quiz_stat;
cursor cur_jc(v_n varchar2) is
select state from cc_quiz_stat;
begin
open cur_cc;
loop
fetch cur_cc
into v_name;
exit when cur_cc%notfound;
open cur_jc(o_cellphone);
loop
fetch cur_jc
into v_state;
exit when cur_jc %notfound;
if (o_cellphone = v_name.cellphone) then
return;
else
dbms_output.put_line('手机号' || v_name.cellphone || '省份' ||
v_state);
end if;
end loop;
close cur_jc;
end loop;
close cur_cc;
end;
end Test5;
执行结果
手机号18900000000省份全国
手机号18900000000省份南京
手机号18900000000省份天津
手机号18900000000省份 上海
手机号18900000000省份北京
代码如下:
create or replace procedure Test5(o_cellphone in varchar2) is
v_cellphone cc_quiz_stat.cellphone %type;
v_name cc_quiz_stat %rowtype;
v_state cc_quiz_stat.state %type;
begin
declare
cursor cur_cc is
select * from cc_quiz_stat;
cursor cur_jc(v_n varchar2) is
select state from cc_quiz_stat;
begin
open cur_cc;
loop
fetch cur_cc
into v_name;
exit when cur_cc%notfound;
open cur_jc(o_cellphone);
loop
fetch cur_jc
into v_state;
exit when cur_jc %notfound;
if (o_cellphone = v_name.cellphone) then
exit;
else
dbms_output.put_line('手机号' || v_name.cellphone || '省份' ||
v_state);
end if;
end loop;
close cur_jc;
end loop;
close cur_cc;
end;
end Test5;
执行结果
手机号18900000000省份全国
手机号18900000000省份南京
手机号18900000000省份天津
手机号18900000000省份 上海
手机号18900000000省份北京
手机号18900000002省份全国
手机号18900000002省份南京
手机号18900000002省份天津
手机号18900000002省份 上海
手机号18900000002省份北京
手机号18900000003省份全国
手机号18900000003省份南京
手机号18900000003省份天津
手机号18900000003省份 上海
手机号18900000003省份北京
手机号18900000004省份全国
手机号18900000004省份南京
手机号18900000004省份天津
手机号18900000004省份 上海
手机号18900000004省份北京
return 跳出整个循环,本循环后面的不再执行,
exit 跳出本次循环,下次继续执行本次循环

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MySQLclusteringenhancesdatabaserobustnessandscalabilitybydistributingdataacrossmultiplenodes.ItusestheNDBenginefordatareplicationandfaulttolerance,ensuringhighavailability.Setupinvolvesconfiguringmanagement,data,andSQLnodes,withcarefulmonitoringandpe

Optimizing database schema design in MySQL can improve performance through the following steps: 1. Index optimization: Create indexes on common query columns, balancing the overhead of query and inserting updates. 2. Table structure optimization: Reduce data redundancy through normalization or anti-normalization and improve access efficiency. 3. Data type selection: Use appropriate data types, such as INT instead of VARCHAR, to reduce storage space. 4. Partitioning and sub-table: For large data volumes, use partitioning and sub-table to disperse data to improve query and maintenance efficiency.

TooptimizeMySQLperformance,followthesesteps:1)Implementproperindexingtospeedupqueries,2)UseEXPLAINtoanalyzeandoptimizequeryperformance,3)Adjustserverconfigurationsettingslikeinnodb_buffer_pool_sizeandmax_connections,4)Usepartitioningforlargetablestoi


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