c++ - 如何摆脱使用但未定义的标签

Question

我正在尝试在嵌入式 sql 中打印表格的行。我有这段代码，其中 publication 是表，pubid 是属性。我试过这个:

    EXEC SQL DECLARE C1 CURSOR FOR SELECT pubid FROM publication;
    EXEC SQL OPEN C1;
    EXEC SQL WHENEVER NOT FOUND GOTO close_c1;
    for(;;) {
        EXEC SQL FETCH C1 INTO :pubid;
        cout<<pubid<<endl;
    }
    close_c1:
    EXEC SQL CLOSE C1;

编译器给我这个错误:错误:标签“close_c1”已使用但未定义。我该如何解决这个问题？

Answer 1

只是猜测...将 WHENEVER 行放在嵌入式 sql 序列的第一位。

来自“SQL 引用第 2 卷”:

WHENEVER
.....
Note:
.....
Every executable SQL statement in a program is within the scope of one implicit or >explicit WHENEVER statement of each type. The scope of a WHENEVER statement is related to the listing sequence of the statements in >the program, not their execution sequence.