Combobox Delegate 25.000 records

Dear All

I am having a problem with a combo box that I use in a tablewidget with a delegate. Combobox has the contents from a sql quary that has 25.000 lines of records. When I press the column in the table that has the combo, it takes nearly 10 sec to display the combo.

Does any body could help for to make it faster!

Quote:

---

Originally Posted by aekilic

Dear All
Combobox has the contents from a sql quary that has 25.000 lines of records.
Does any body could help for to make it faster!

---

From mysql or sqlite?

I have a 15000 contact mysql table if i run from from intranet the loading is 3-4 second
if i copy on a ( therad process ) mysql table on a sqlite3 memory table it display on 1 second..

I use postgres, but the solution could be help full, could you please tell me how you did it?

I am a bit new to Qt...

I write the network table to sqlite :memory: ram..

Simply here a sample ....
ad work on 2 connection cache & intranet

Code:

---

/* open big database !!!! */
    /* i use sheme = "mysql://username:pass@host:port/database"  */
    QUrl dns(sheme,QUrl::TolerantMode);
    const QString dbase = dns.path().replace("/","");
    QStringList drivers = QSqlDatabase::drivers();
    type = "Q"+dns.scheme().toUpper();
	  std::cout << "######### type   " << qPrintable(type ) << "\n" << std::endl;
    if (!drivers.contains(type)) {
    std::cout << "######### " << qPrintable(tr("Unable to Load Driver %1").arg(type)) << "\n" << std::endl;
    return false;      
    }
    ////  .....user port and so .............
		db = QSqlDatabase::addDatabase(type,QString("master_mysql_%1").arg(trac));
    /* open QSQLITE on ram */
    cachedb = QSqlDatabase::addDatabase("QSQLITE");
    cachedb.setDatabaseName(":memory:");
     if (!cachedb.open()) {
        QMessageBox::critical(0, qApp->tr("Cannot open local database"),
            qApp->tr("Unable to establish a cache database connection.\n\n"
                     "Click Cancel to exit."), QMessageBox::Cancel);
        return false;
    }
 
    LoadCache();
 
  /* fill memory table to quick load and runn query */
  /* update i send to db mysql if needed relaod LoadCache() */
void DB_Manager::LoadCache()
{
    QSqlQuery query("",cachedb);
    QApplication::setOverrideCursor(QCursor(Qt::WaitCursor));
    query.exec("DROP TABLE IF EXISTS catememo");
    query.exec("create table catememo (id INTEGER PRIMARY KEY AUTOINCREMENT,root_id INTEGER,name varchar(110),lft INTEGER,rgt INTEGER,oldid INTEGER,xmlattribute BLOB)");
    QStringList line_data;
    QSqlQueryModel *mod = new QSqlQueryModel();
    mod->setQuery(QString("SELECT * FROM %1 ").arg(TABELLA_CATES),current());
    const int summline = mod->rowCount();
 
    for (int e = 0; e < summline; ++e) {
        line_data.clear();
        QSqlRecord r = mod->record(e);
               for (int x = 0; x < mod->columnCount(); ++x)  {
                   QString cellTxt = "'"+G_Quote(r.value(x).toString())+"'";
                   line_data.append(cellTxt);
               }
        QString cainsert = QString("insert into catememo values (%1)").arg(line_data.join(","));
        bool mcis = query.exec(cainsert);
    }
 
    QApplication::restoreOverrideCursor(); 
}

---

Should I have to write this to delegate?

Second thing is first you disconnect with the current server and than you copy them to sqlite?

Quote:

---

Originally Posted by aekilic

Should I have to write this to delegate?

---

No, i have make a extra DBconnect manager to call other utility
after first connect i fill cache...

Quote:

---

Second thing is first you disconnect with the current server and than you copy them to sqlite?

---

If connection is open from server you can reload table any time...


a extra DB manager i send instance to other widged or class to manage and fill combobox or export mysql dump ecc..


here is a piece on dir
http://ppk.ciz.ch/qt_c++/cms_layer/
http://ppk.ciz.ch/qt_c++/cms_layer/DB_Manager.h
http://ppk.ciz.ch/qt_c++/cms_layer/DB_Manager.cpp

Hello everybody,

I have connected 2 database for the program,

Code:

---

db = QSqlDatabase::addDatabase("QPSQL");
 		db.setHostName("10.0.0.11");
 		db.setPort(5432);
		db.setDatabaseName(comboDonem->currentText());
		db.setUserName(lineKullanici->text());
		db.setPassword(lineSifre->text());

---

and the other one is

Code:

---

QSqlDatabase::database("in_mem_db", false).close();
	QSqlDatabase::removeDatabase("in_mem_db");
	cachedb = QSqlDatabase::addDatabase("QSQLITE", "in_mem_db");
	cachedb.setDatabaseName(":memory:");
	if (!cachedb.open())
	{
		QMessageBox::warning(this, tr("Unable to open database"), tr("An error occured while opening the connection: ") + cachedb.lastError().text());
		return false;
	}

---

I could load the cache and select from cache. But the problem I have is when I go to another page(another .h file), I could not connect to cache. I could only connect db. (PQSQL)

I want to know How could I connect the cache and select from there.

simple point your cache connecion on query

QSqlQuery query("",cachedb);

like sql example

connect / query to first db is
QSqlQuery query();
connect / query to sqlite memory
QSqlQuery query("",cachedb);

you can now query to all db listed on
QStringList QSqlDatabase::connectionNames () [static]

if you not like to save db pointer:

QSqlDatabase QSqlDatabase::database ( const QString & connectionName = QLatin1String( defaultConnection ), bool open = true ) [static]

Dear Patric

Thank you for your reply again, but it didnt solve my problem actually.

Should I have to connect to cachedb on main.cpp?

Because what I do is on main cpp starts a entrance .ui which you log on the postgresql. In which i also connect to cachedb. After that you go to the mainpage.h. The problem I have is I could not connect to cache in the mainpage.h

Dear Patric,

I am trying mybest. But when I close the form that I created cachedb, and open another form, I lost connectiong to the cachedb. But default db connection(PQSQL) stays. Please help me...