Question

我写了一个ecpg代码。我试图根据表中是否已存在元组，将元组插入表中。我正在编译时出现“错误：break语句不在循环内或切换”请帮忙我在代码中评论了编译器显示错误的行

EXEC SQL DECLARE cursor4 CURSOR FOR
select count(*)
from works_on
where pno = :project
and essn = :ssn;

EXEC SQL OPEN cursor4;
EXEC SQL WHENEVER NOT FOUND DO BREAK;

while (SQLCODE==0)
{
EXEC SQL FETCH IN cursor4 INTO :cnt; 
}

EXEC SQL CLOSE cursor4;
EXEC SQL BEGIN DECLARE SECTION;
const char *qry = "INSERT INTO WORKS_ON VALUES(?,?,?);";
EXEC SQL END DECLARE SECTION;

if (cnt == 0 )
{
EXEC SQL PREPARE mystmt from :qry;
exec sql execute mystmt using '123456789',3,5.0; // where i am getting error

}

Answer 1

执行WHENEVER句子，直到它在代码中找到另一个WHENEVER。你必须在你的bucle之后取消 WHENVER NOT FOUND break 。

EXEC SQL DECLARE cursor4 CURSOR FOR
select count(*)
from works_on
where pno = :project
and essn = :ssn;

EXEC SQL OPEN cursor4;
EXEC SQL WHENEVER NOT FOUND DO BREAK;

while (SQLCODE==0)
{
EXEC SQL FETCH IN cursor4 INTO :cnt; 
}
EXEC SQL WHENEVER NOT FOUND CONTINUE;   //Add this line to your code.

EXEC SQL CLOSE cursor4;
EXEC SQL BEGIN DECLARE SECTION;
const char *qry = "INSERT INTO WORKS_ON VALUES(?,?,?);";
EXEC SQL END DECLARE SECTION;

if (cnt == 0 )
{
EXEC SQL PREPARE mystmt from :qry;
exec sql execute mystmt using '123456789',3,5.0;

ecpg错误：break语句不在循环或开关内

1 个答案: