在C语言中使用查询变量的SQL语句

我正在构建一个访问SQL数据库的c++程序。我能够连接并返回以下语句的值:

retcode = SQLExecDirect(hstmt, (SQLWCHAR*)L"SELECT Beta FROM Equity WHERE Ticker = 'AAPL'", SQL_NTS);

但是，我希望能够将'AAPL'替换为字符串'ticker'，该字符串可以使用cin>>定义。

有什么办法可以做到吗?

感谢您的帮助，完整的代码如下:

#include "stdafx.h"
#include <iostream>
#include <windows.h>
#include <sql.h>
#include <sqltypes.h>
#include <sqlext.h>
#include <string>
using namespace std;
int main(){
    SQLHENV henv;
    SQLHDBC hdbc;
    SQLHSTMT hstmt;
    SQLRETURN retcode;
    SQLWCHAR OutConnStr[255];
    SQLSMALLINT OutConnStrLen;
    // Allocate environment handle
    retcode = SQLAllocHandle(SQL_HANDLE_ENV, SQL_NULL_HANDLE, &henv);
    // Set the ODBC version environment attribute
    if (retcode == SQL_SUCCESS || retcode == SQL_SUCCESS_WITH_INFO) {
        retcode = SQLSetEnvAttr(henv, SQL_ATTR_ODBC_VERSION, (void*)SQL_OV_ODBC3, 0); 
        // Allocate connection handle
        if (retcode == SQL_SUCCESS || retcode == SQL_SUCCESS_WITH_INFO) {
            retcode = SQLAllocHandle(SQL_HANDLE_DBC, henv, &hdbc); 
             // Set login timeout to 5 seconds
            if (retcode == SQL_SUCCESS || retcode == SQL_SUCCESS_WITH_INFO) {
                SQLSetConnectAttr(hdbc, SQL_LOGIN_TIMEOUT, (SQLPOINTER)5, 0);
                // Connect to data source
                retcode = SQLDriverConnect(
                    hdbc, 
                    0,
                    (SQLWCHAR*)L"DSN=Phoenix;SERVER=XXX;UID=XXX;PWD=XXX;DRIVER=MySQL Server;", 
                    _countof(L"DSN=Phoenix;SERVER=XXX;UID=XXX;PWD=XXX;DRIVER=MySQL Server;"),
                    OutConnStr,
                    255, 
                    &OutConnStrLen,
                    SQL_DRIVER_COMPLETE );
                // Allocate statement handle
                if (retcode == SQL_SUCCESS || retcode == SQL_SUCCESS_WITH_INFO) {
                    retcode = SQLAllocHandle(SQL_HANDLE_STMT, hdbc, &hstmt); 
                    // Process data
                    string  ticker;
                    cout << " Enter Ticker:     "; //Prompt Ticker
                    cin >> ticker;      //Stores Ticker
                    //retcode = SQLExecDirect(hstmt, (SQLWCHAR*)L"SELECT Beta FROM Equity WHERE Ticker = 'AAPL'", SQL_NTS);
                    retcode = SQLExecDirect(hstmt, (SQLWCHAR*)L"SELECT Beta FROM Equity WHERE Ticker = ticker", SQL_NTS);
                    if (retcode == SQL_SUCCESS) {
                        SQLINTEGER cbTestStr, iCount = 1;
                        SQLFLOAT dTestFloat;
                        SQLCHAR beta[200];
                        while (TRUE) {
                            retcode = SQLFetch(hstmt);
                            if (retcode == SQL_ERROR || retcode == SQL_SUCCESS_WITH_INFO) {
                                cout<<"An error occurred";
                            }
                            if (retcode == SQL_SUCCESS || retcode == SQL_SUCCESS_WITH_INFO){
                                SQLGetData(hstmt, 1, SQL_C_CHAR, beta, 200, &cbTestStr);
                                /* Print the row of data */
                                cout<<"Beta for "<< ticker << " = " << beta <<endl;
                                double bi;
                                cin >> bi;

                            } else {
                                break;
                            }
                        }
                    }else{
                        cout<<"Query execution error."<<endl;
                    }
                    SQLFreeHandle(SQL_HANDLE_STMT, hstmt);
                    SQLDisconnect(hdbc);
                }else{ 
                    cout<<"Connection error"<<endl;
                }
                SQLFreeHandle(SQL_HANDLE_DBC, hdbc);
            }
        }
        SQLFreeHandle(SQL_HANDLE_ENV, henv);
    }
        system("pause");
    return 0;
}