Question

I am trying to insert huge data in sqlite, to gain performance, I am using transaction statement. My code looks like this:
CSVParser parser;

   query.exec("BEGIN TRANSACTION;");
   while (!file.atEnd())
    {
           line = file.readLine();
           if (line == "")
                  continue;
            parser << line.toStdString(); // Feed the line to the parser
                // Now extract the columns from the line
            parser >> sCol1 >> sCol2 >> sCol3 >> sCol4;

            // Method one to insert data
            sqlQuery = "INSERT INTO Person(phone, name, firstname, lastname) VALUES (" \
                         "'" + QString(sCol1.c_str()) + \
                         "','" + QString(sCol2.c_str()) + \
                         "','" + QString(sCol4.c_str()) + \
                         "','" + QString(sCol3.c_str()) + "')";
            //query.exec(sqlQuery);

            // Method two to insert data
             query.prepare("INSERT INTO Person(phone, name, firstname, lastname) VALUES (:phone, :name, firstname, :lastname");
             query.bindValue(":phone", QString(sCol1.c_str()));
             query.bindValue(":name", QString(sCol2.c_str()));
             query.bindValue(":firstname", QString(sCol4.c_str()));
             query.bindValue(":lastname", QString(sCol3.c_str()));
             query.exec();
             cout << query.lastError().text().toStdString();
      }

   query.exec("END TRANSACTION;");  

If I use the first method, the data inserted fine, but the problem may occur later if a text contains charcarter like this “‘”. To avoid this, I switched to prepared statement, a new problem, no data inserted. The only error I see:

Parameter count mismatch Parameter count mismatch Parameter count
mismatch Parameter count mismatch Parameter count mismatch Parameter
count mismatch Parameter count mismatch Parameter count mismatch
Is there I am missing here?

Answer 1

I wonder if this is the cause:

query.prepare("INSERT INTO Person(phone, name, firstname, lastname)
    VALUES (:phone, :name, firstname, :lastname");
                                              ^^^
         missing close paren inside the string^^^