嵌入式SQL与主语言的通信_MySQL

#include
#include

EXEC SQL BEGIN DECLARE SECTION; /*主变量说明开始*/ 
char deptname[64];
char HSno[64];
char HSname[64]; 
char HSsex[64];
int HSage;
int NEWAGE;
long SQLCODE;
EXEC SQL END DECLARE SECTION;     /*主变量说明结束*/

EXEC SQL INCLUDE sqlca;               /*定义SQL通信区*/

/*************************************************************************/

int main(void)                           /*C语言主程序开始*/
{
int count = 0;
char yn;                              /*变量yn代表yes或no*/
printf("Please choose the department name(CS/MA/IS): "); 
scanf("%s", deptname);                 /*为主变量deptname赋值*/
EXEC SQL CONNECT TO HP-08D6CXF128B/SQL2000 USER sa;         /*连接数据库TEST*/
EXEC SQL DECLARE SX CURSOR FOR   /*定义游标*/
SELECT Sno, Sname, Ssex, Sage   /*SX对应语句的执行结果*/
FROM Student
WHERE SDept = :deptname;
EXEC SQL OPEN SX;        /*打开游标SX便指向查询结果的第一行*/

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for ( ; ; )                       /*用循环结构逐条处理结果集中的记录*/
{ 
EXEC SQL FETCH SX INTO :HSno, :HSname, :HSsex,:HSage;
      /*推进游标，将当前数据放入主变量*/
if (sqlca->sqlcode != 0)     /* sqlcode != 0,表示操作不成功*/
break;                /*利用SQLCA中的状态信息决定何时退出循环*/
if(count++ == 0)             /*如果是第一行的话，先打出行头*/
printf("/n%-10s %-20s %-10s %-10s/n", "Sno", "Sname", "Ssex", "Sage");
printf("%-10s %-20s %-10s %-10d/n", HSno, HSname, HSsex, HSage); 
     /*打印查询结果*/
printf("UPDATE AGE(y/n)?"); /*询问用户是否要更新该学生的年龄*/
do{                     
    scanf("%c",&yn);
}
while(yn != 'N' && yn != 'n' && yn != 'Y' && yn != 'y');
if (yn == 'y' || yn == 'Y')                 /*如果选择更新操作*/
{
   printf("INPUT NEW AGE:");
   scanf("%d",&NEWAGE);          /*用户输入新年龄到主变量中*/
   EXEC SQL UPDATE Student            /*嵌入式SQL*/
   SET Sage = :NEWAGE
   WHERE CURRENT OF SX ;
}                 /*对当前游标指向的学生年龄进行更新*/
}

EXEC SQL CLOSE SX;           /*关闭游标SX不再和查询结果对应*/
EXEC SQL COMMIT WORK;                           /*提交更新*/
EXEC SQL DISCONNECT TEST;                  /*断开数据库连接*/
}