How to Retrive data...?

[gunturrohith]

Hi i am trying to retrive the data from the database here is my program

Intially i am entering the mobile no in a line edit which i have named it as "searchedit" and then i am strong the data of line edit into a string and then i am trying to reterive the data from the database by the help mobile number which is present in the string and i have written the query as beolw

QString str1 = searchedit->text();
searchedit->setText(str1);

int ret;
QSqlQuery query;
query.exec("SELECT * FROM details WHERE mobile="(str1.data())"");

i am storing the data in a line edit into a string and then i am trying to retrive the data from the database which matches with the data present in the string,but it is showing an error " '"SELECT * FROM details WHERE mobile="' cannot be used as a function"

I need to retirve the details of the user by the help of their mobile numbers.

Please help to retrive the data from the data base i am using the sqlite database and my QT version is 4.7.4

Thanks in advance
Rohith.G

[wysota]

Your code has incorrect C++ syntax. QSqlQuery docs contains an example how to build a query with parameters using QSqlQuery::prepare().

[gunturrohith]

Sorry can you please elaborate the explanation i have not got anything which is familiar to my question in the QSqlQuery

[wysota]

Click the second link in my post, read the docs and evaluate the code in the big gray box.

[gunturrohith]

Hi thanks for your help and i have made some modifications in my code once please go through this and tell me where i am making mistake..?
Here is my code

QString str1 = searchedit->text();
        //searchedit->setText(str1);
        QString str("SELECT * FROM details WHERE mobile=");
 
        QString finalStr = str+ str1.toAscii().data();
        qDebug()<<"Data in FinalStr:"<<finalStr;
        bool ret;
        QSqlQuery query;
        //ret=query.exec("SELECT * FROM details WHERE mobile='str1.toAscii().data()'");
        query.prepare("finalstr");
        ret=query.exec();
 
        if(ret==true)
        {
        qDebug("comparison success");
        QMessageBox msgbox;
        msgbox.setText("<h5>Registered User</h5>");
        msgbox.exec();
        }
        else
        {
        QMessageBox msgbox;
        msgbox.setText("Not Registered");
        msgbox.exec();
        }
* * * *

QString str1 = searchedit->text();
        //searchedit->setText(str1);
        QString str("SELECT * FROM details WHERE mobile=");

        QString finalStr = str+ str1.toAscii().data();
        qDebug()<<"Data in FinalStr:"<<finalStr;
        bool ret;
        QSqlQuery query;
        //ret=query.exec("SELECT * FROM details WHERE mobile='str1.toAscii().data()'");
        query.prepare("finalstr");
        ret=query.exec();

        if(ret==true)
        {
        qDebug("comparison success");
        QMessageBox msgbox;
        msgbox.setText("<h5>Registered User</h5>");
        msgbox.exec();
        }
        else
        {
        QMessageBox msgbox;
        msgbox.setText("Not Registered");
        msgbox.exec();
        }
* * * *

To copy to clipboard, switch view to plain text mode 

This code producing a result as Not Registered even if the data is present in the database
Please help me
Thanks in advance
Rohith.G

[wysota]

query.prepare("finalstr");

query.prepare("finalstr");

To copy to clipboard, switch view to plain text mode 

I don't think this is a valid SQL query. Do you know what is a string in c++ and how does it differ from a variable identifier?