过程中的 PL/SQL 游标不起作用
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【中文标题】过程中的 PL/SQL 游标不起作用【英文标题】：PL/SQL Cursor in Procedure doesn't work 【发布时间】：2016-01-26 19:41:02 【问题描述】：好吧，我的数据库中有培训师和认证表（类似于学位或执照），我正在尝试创建程序，对于给定的培训师 ID 和新日期，该程序将更新此人的执照。
CREATE TABLE Trainer
(
trainer_id number(10) PRIMARY KEY,
name varchar2(15),
surname varchar2(15),
address varchar2(50),
phone number(8),
certification number(10)
);
INSERT INTO Trainer
VALUES(null, 'John', 'Climps', 'Blowing St, 134',18273643, 10);
INSERT INTO Trainer
VALUES(null, 'Bill', 'Spark', 'Academic St, 2', 28947384, 2);
INSERT INTO Trainer
VALUES(null, 'Olga', 'Redric', 'Captain Jack St, 7', 11862343, 6);
INSERT INTO Trainer
VALUES(null, 'Alex', 'Rose', 'Green St, 98', 18238633, 4);
INSERT INTO Trainer
VALUES(null, 'Monna', 'Lebindsky', 'Doge St, 1', 18685663, 5);
INSERT INTO Trainer
VALUES(null, 'Jack', 'Not', 'Tahon St, 76', 28941643, 3);
INSERT INTO Trainer
VALUES(null, 'Max', 'Scheight', 'Red Forrest St, 25', 28164064, 7);
INSERT INTO Trainer
VALUES(null, 'Emily', 'Ruby', 'Main St, 8', 1894636474, 8);
INSERT INTO Trainer
VALUES(null, 'Linda', 'Glaze', 'Yelecki St, 63', 18462343, 9);
INSERT INTO Trainer
VALUES(null, 'Merry', 'Gold', 'Main St, 101', 18434334, 1);
DROP TABLE Certification;
CREATE TABLE Certification
(
certific_id number(10) PRIMARY KEY,
name varchar2(50),
description varchar2(1000),
date_of_achieve varchar2(8),
date_of_expire varchar2(8)
);
INSERT INTO Certification
VALUES(null, 'Fitness trainer', 'Course for a beginner fitness trainer',
'09.10.15', '09.10.16');
INSERT INTO Certification
VALUES(null, 'Fitness trainer', 'Course for a advanced fitness trainer',
'17.07.13', '13.07.16');
INSERT INTO Certification
VALUES(null, 'Football trainer', 'Degree of a football trainer', '11.01.12',
'01.10.16');
INSERT INTO Certification
VALUES(null, 'Tennis trainer', 'Degree of a tennis trainer', '25.05.15',
'12.04.18');
INSERT INTO Certification
VALUES(null, 'Swimming trainer', 'Course for a swimming trainer for children',
'18.10.14', '18.10.17');
INSERT INTO Certification
VALUES(null, 'Yoga master', 'Achieved after special yoga and medidation
cources in India','01.12.13', '15.04.16');
INSERT INTO Certification
VALUES(null, 'Sport master', 'Specialist in all sport activities', '14.03.14',
'14.03.18');
INSERT INTO Certification
VALUES(null, 'Fitness trainer', 'Master in workouts', '11.09.15', '11.03.18');
INSERT INTO Certification
VALUES(null, 'Equipment specialist', 'Master and instrucor of gym equipments',
'30.09.12', '30.01.16');
INSERT INTO Certification
VALUES(null, 'Boxer', 'Master in martial arts and boxing', '27.11.13',
'17.12.16');
这是我的程序
CREATE OR REPLACE PROCEDURE updateTrainerCertificate(trainerID in number, nextDate in varchar)
AS
no_trainer exception;
no_name exception;
invalid_date exception;
no_certificate exception;
tr_id number(10);
tr_name varchar2(50);
certific number(10);
new_day_achieve varchar(8);
Begin
SELECT trainer_id INTO tr_id FROM Trainer WHERE trainer_id = trainerID;
if tr_id is null then raise no_trainer;
else
SELECT name INTO tr_name FROM Trainer WHERE trainer_id = tr_id;
if tr_name is null then no_name;
else
SELECT certification INTO certific FROM Trainer, Certification
WHERE Trainer.certification = Certification.certific_id
AND trainer_id = tr_id;
if certificate in null then raise no_certificate;
else
SELECT TO_CHAR(sysdate, 'DD.MM.YY') INTO new_day_achieve
FROM DUAL;
if LENGTH(new_day_achieve) != 8 or LENGTH(nextDate) != 8
then raise invalid_date;
else
UPDATE Certification SET date_of_achieve = new_date_achieve,
date_of_expire = nextDate
WHERE certific_id = certific;
DBMS_output.put_line(tr_name || ' updated certificate from '
|| new_day_achive || ' till ' || nextDate);
end if;
end if;
end if;
end if;
exception
when no_trainer then dbms_output.put_line('No trainer found');
when no_name then dbms_output.put_line('Error. Trainer without name.
Check table Trainer');
when invalid_date then dbms_output.put_line('Invalid date format');
when no_certificate then dbms_output.put_line('Trainer does not have any
certificate');
End;
/
编译显示难以理解的错误
【问题讨论】：
【参考方案1】：创建表和插入数据的代码错误，它尝试在非空列中插入一些空值。
在程序中，变量名错误，此代码为我编译：
CREATE OR REPLACE PROCEDURE updateTrainerCertificate(trainerID in number, nextDate in varchar)
AS
no_trainer exception;
no_name exception;
invalid_date exception;
no_certificate exception;
tr_id number(10);
tr_name varchar2(50);
certific number(10);
new_day_achieve varchar(8);
Begin
SELECT trainer_id INTO tr_id FROM Trainer WHERE trainer_id = trainerID;
if tr_id is null then raise no_trainer;
else
SELECT name INTO tr_name FROM Trainer WHERE trainer_id = tr_id;
if tr_name is null then raise no_name;
else
SELECT certification INTO certific FROM Trainer, Certification
WHERE Trainer.certification = Certification.certific_id
AND trainer_id = tr_id;
if certific is null then raise no_certificate;
else
SELECT TO_CHAR(sysdate, 'DD.MM.YY') INTO new_day_achieve
FROM DUAL;
if LENGTH(new_day_achieve) != 8 or LENGTH(nextDate) != 8
then raise invalid_date;
else
UPDATE Certification SET date_of_achieve = new_day_achieve,
date_of_expire = nextDate
WHERE certific_id = certific;
DBMS_output.put_line(tr_name || ' updated certificate from '
|| new_day_achieve || ' till ' || nextDate);
end if;
end if;
end if;
end if;
exception
when no_trainer then dbms_output.put_line('No trainer found');
when no_name then dbms_output.put_line('Error. Trainer without name.
Check table Trainer');
when invalid_date then dbms_output.put_line('Invalid date format');
when no_certificate then dbms_output.put_line('Trainer does not have any
certificate');
End;
/
我在 SQLDeveloper 4.0.3.16 中编译过，所有错误都在“编译器日志”窗口中可见，并指出错误所在行和原因
【讨论】：
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