The following code example shows how to bind parameters to create parameterized statements.

Binding Parameters

Use the SQLBindParameter function to bind the specified parameter position to the specified variable. Note that the parameter order starts at 1.

Example

The following example executes a parameterized SELECT and iterates over the results. You can use SQLExecDirect to execute any parameterized statement.

  SQLHENV henv;
  SQLHDBC hdbc;
  SQLHSTMT hstmt;
  char sStudent_ID[30] = {0};
  SQLLEN cbsStudent_ID = 0;
  char param[30] = {0};
  strcpy(param, "US");
  SQLLEN cbParam = SQL_NTS;
  if (SQLAllocHandle(SQL_HANDLE_ENV, 0 ,&henv) == SQL_SUCCESS) {
    SQLSetEnvAttr(henv, SQL_ATTR_ODBC_VERSION, (void*)SQL_OV_ODBC3, 0); 
    if (SQLAllocHandle(SQL_HANDLE_DBC, henv ,&hdbc) == SQL_SUCCESS) {
      if (SQLConnect(hdbc, "CData Btrieve Source", SQL_NTS, 0, 0, 0, 0) == SQL_SUCCESS) {
        if (SQLAllocHandle(SQL_HANDLE_STMT, hdbc ,&hstmt) == SQL_SUCCESS) {
          SQLBindParameter(hstmt, 1, SQL_PARAM_INPUT, SQL_C_CHAR, SQL_CHAR, 100, 0, (SQLPOINTER)param, 30, &cbParam);
          if (SQLExecDirect(hstmt, "SELECT Student_ID FROM [CData].[Btrieve].Billing WHERE Student_ID = ?", SQL_NTS) == SQL_SUCCESS) {
            while(SQLFetch(hstmt) == SQL_SUCCESS) {
              if (SQLGetData(hstmt, 1, SQL_C_CHAR, (SQLPOINTER)sStudent_ID, 255, &cbsStudent_ID) == SQL_SUCCESS) {
                printf("Student_ID: %s\n", sStudent_ID);
              }
            }
          }
          SQLFreeHandle(SQL_HANDLE_STMT, hstmt);
        }
        SQLDisconnect(hdbc);
      }
      SQLFreeHandle(SQL_HANDLE_DBC, hdbc);
    }
    SQLFreeHandle(SQL_HANDLE_ENV, henv);
  }