c语言关于从数据库读取数据写文件

#include  <stdio.h>

exec sql include sqlca

int main(){

    exec sql begin declare section

        char userpasswd[30]="openlab/123456"

        struct{

            int  id

            char name[30]

            double salary

        }emp

    exec sql end   declare section

    exec sql connect:userpasswd

    exec sql declare empcursor cursor for 

        select id,first_name,salary  from 

        s_emp order by salary

    exec sql  open  empcursor

    exec sql  whenever notfound do break

    for(){

    exec sql  fetch empcursor into :emp

    printf("%d:%s:%lf\n",emp.id,emp.name,

                     emp.salary)

    }

    exec sql  close empcursor

    exec sql commit work release    

}

把数据存到结构体里。

private void GetDataByParmSqlCommand()\x0d\x0a{\x0d\x0aSqlConnection sqlc = new SqlConnection(DBUtility.SqlHelper.ConnectionStringLocalTransaction) //取连接字符串饼建立sqlconnection\x0d\x0atry\x0d\x0a{\x0d\x0a\x0d\x0asqlc.Open()\x0d\x0aSqlCommand com = new SqlCommand("select * from c6 where usr_id = usr_id", sqlc)\x0d\x0aSqlParameter parm = new SqlParameter()\x0d\x0aparm.ParameterName = "@usr_id"\x0d\x0aparm.Value = "01\x0d\x0acom.Parameters.Add(parm)\x0d\x0acom.ExecuteNonQuery()\x0d\x0aDataSet ds = new DataSet()\x0d\x0aSqlDataAdapter sda = new SqlDataAdapter(com)\x0d\x0asda.Fill(ds, "c6")\x0d\x0aDataTable dt = ds.Tables[0]\x0d\x0atextbox.Text ="用户代码："+ dt.Rows[0]["usr_id"].ToString().Trim() +"用户名称："+ dt.Rows[0]["usr_name"].ToString().Trim() \x0d\x0a//这样组合一下就可以了,看你要显示哪些信息\x0d\x0a\x0d\x0a}\x0d\x0acatch (Exception ee)\x0d\x0a{\x0d\x0aMessageBox.Show(ee.Message, "")\x0d\x0a}\x0d\x0afinally\x0d\x0a{\x0d\x0asqlc.Close()\x0d\x0a}\x0d\x0a}

int CountLines(char *filename) { ifstream ReadFileint n=0char line[512]ReadFile.open(filename,ios::in)//ios::in 表示以只读的方式读取文件 if(ReadFile.fail())//文件打开失败:返回0 { return 0} else//文件存在 { while(!ReadFile.eof()) { ReadFile.getline(line,512,'\n')n++} return n}

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