The SQLite exception "no such table: <table> Unable to execute statement" with QSqlDatabase

Maarouf Med Mahdi

welcome,
I opened my database sqlite in Qt without error and I checked that all the tables are well created in the base and well the path of the base. but when I try to execute a query I get an error (no such table: <table> Unable to execute statement).
I am sure that I connected to a real base and that it contains all the table .
Someone you can help me please.

Taz742

@Maarouf-Med-Mahdi
Can you post your query?

Maarouf Med Mahdi

@Taz742

// --connecting data base code :

   mydb=QSqlDatabase::addDatabase("QSQLITE");

    mydb.setDatabaseName("D:\Applications\App Gestion Data CenterV2\GestionDataCenterV2\GestionDataCenter_BD.db");
    if(mydb.open())
        qDebug() << "connected";
    else
        qDebug() << "deconnected";

// --executing query code : 
 QSqlQuery requette;
 QString text_req = "insert into serveurs values('123.112.113','Phisique',1,2,3,3,'01/01/1997','12/01/1997');";

 if(requette.exec(text_req))
     qDebug()<<"requette valide";
 else
     qDebug()<<"invalide requette"<<" --> "<<requette.lastError().text();

Taz742

@Maarouf-Med-Mahdi said in How insert data into sqlite database with Qt:

insert into serveurs values('123.112.113','Phisique',1,2,3,3,'01/01/1997','12/01/1997');"

It is a valid query?
Does this query work in sql without Qt?

Maarouf Med Mahdi

Yes , i tested the same query before execute with Qt .

Vinod Kuntoji

@Maarouf-Med-Mahdi ,

Path of DB file contains some spaces. Remove those spaces and try.

Maarouf Med Mahdi

@Vinod-Kuntoji
qt connected well to my database and i have run other query like
select * from sqlite_master where tbl_name = '<table>' "; it works to show you that the path of bd is valid,

JonB

@Maarouf-Med-Mahdi
You said:

(no such table: <table> Unable to execute statement).

So it's telling you there is no table named whatever it reports for <table> (really wish you'd give the actual text of the error message, then we'd know....)

Your statement is:
insert into serveurs ...
so, assuming it reports serveurs as the table name, there is no such table as serveurs in whatever is your current database....

P.S.
Have you tried SELECT * FROM serveurs in your Qt code for yourself, to decide whether it's really an INSERT problem?

Taz742

@Maarouf-Med-Mahdi
Try:

QSqlQuery query;
query.prepare("insert into serveurs (field1, field2, field3) values (:value1, :value2, :value3)");
query.bindValue(":value1," MyValue1);
query.bindValue(":value2", MyValue2);
query.bindValue(":value3", MyValue3);

if (query.exec()) {
    //
} else {
    qDebug() << query.lastError().text();
}

JonB

@Taz742
https://sqlite.org/lang_insert.html is telling you that the list of column/field names is optional in INSERT INTO, if that's what you're trying to tell the OP to correct to.

Vinod Kuntoji

@Maarouf-Med-Mahdi ,
Are you sure, your table name is correct?

Maarouf Med Mahdi

@Vinod-Kuntoji yes i m sure

Maarouf Med Mahdi

@JNBarchan that is my dataBase file

-- Fichier généré par SQLiteStudio v3.1.1 sur mer. déc. 13 21:27:34 2017

-- Encodage texte utilisé : System

PRAGMA foreign_keys = off;
BEGIN TRANSACTION;

-- Table : historiques
CREATE TABLE historiques(
IP varchar(20) ,
date_modification date,
anc_type_serveur varchar(10),
anc_croire int (10),
anc_rack int(10),
anc_chassis int (4),
anc_position int (10),
constraint FK_historiques foreign key (IP) references serveurs(IP)
);

-- Table : serveurs
CREATE TABLE serveurs (
IP varchar(20) ,
type_serveur varchar(10),
croire int (10),
rack int(10),
chassis int (4),
position int (10),
date_creation date,
date_der_accee date,
constraint PK_serveurs primary key (IP)
);

COMMIT TRANSACTION;
PRAGMA foreign_keys = on;

Maarouf Med Mahdi

@JNBarchan I give you the result of this query
select * from serveurs;
***the code:
mydb.setDatabaseName("D:\Applications\App Gestion Data CenterV2\GestionDataCenterV2\GestionDataCenter_BD.db");
if(mydb.open())
qDebug() << "connected";
else
qDebug() << "deconnected";

QSqlQuery requette;
QString text_req = "select * from serveurs;";
if(requette.exec(text_req))
qDebug()<<"requette valide";
else
qDebug()<<"invalide requette"<<" --> "<<requette.lastError().text();
***the debug
connected
invalide requette --> "no such table: serveurs Unable to execute statement"

Maarouf Med Mahdi

@Taz742 this query shows me the same error
QString text_req = "insert into serveurs('IP','type_serveur','croire','rack','chassis','position','date_creation','date_der_accee') values('123.112.113','Physique',1,2,3,3,'01/01/1997','12/01/1997');";

// I wish you saw my database I posted it

Stoyan

@Maarouf-Med-Mahdi
This message also prove that there is no such table in your database.
You can check which tables are available with this code:

if(mydb.open())
        qDebug() << "connected";
    else
        qDebug() << "deconnected";
qDebug() << "Tables: " << mydb.tables();

Maybe there is a difference in some letter in other code page (UTF-8 vs ANSI).

Maarouf Med Mahdi

Hi @Stoyan that show me (), i think you saw my db i posted it ,
all tables has been created but Qt can not find it

Maarouf Med Mahdi

@Stoyan previously I used the encoding "system", now I've changed to UTF-8 but the same error still see

Stoyan

@Maarouf-Med-Mahdi
It seems that you are not connected to the database.
Try to change your code for open database.
Instead:

if(mydb.open())
        qDebug() << "connected";
    else
        qDebug() << "deconnected";

use this:

    if(!mydb.open())
    {
        qDebug() << mydb.lastError().text();
    }

BTW, what is the result from query that you use to test database connection:

select * from sqlite_master where tbl_name = 'serveurs';

Maarouf Med Mahdi

@Stoyan connected and that query works
select * from sqlite_master where tbl_name = 'serveurs';

Stoyan

@Maarouf-Med-Mahdi
OK, but what is the result? Empty set or 2-3 rows?

Stoyan

In SQLite a database is a single file. And I think that, if database file don't exists it is created and practically the connection is made to new empty database.
You can search on your computer for file with the name "GestionDataCenter_BD.db". I guess that there will be another such file in other folder than original database.

Maarouf Med Mahdi

@Stoyan i understood what you said, but i m sure i connected to the real database from a real path
mydb.setDatabaseName("D:\Applications\App Gestion Data CenterV2\GestionDataCenterV2\GestionDataCenter_BD.db");

karlheinzreichel

I think the answer is quite simple:
use double backslash!

instead of

 mydb.setDatabaseName("D:\Applications\App Gestion Data CenterV2\GestionDataCenterV2\GestionDataCenter_BD.db");

use

 mydb.setDatabaseName("D:\\Applications\\App Gestion Data CenterV2\\GestionDataCenterV2\\GestionDataCenter_BD.db");

regards
Karl-Heinz

Maarouf Med Mahdi

Hi @karlheinzreichel , i got that message
connected
invalide requette --> "file is encrypted or is not a database Unable to execute statement"

karlheinzreichel

@Maarouf-Med-Mahdi said in How insert data into sqlite database with Qt:

(no such table: <table> Unable to execute statement).

But before you get the error:
(no such table: <table> Unable to execute statement).

now you get
file is encrypted or is not a database Unable to execute statement

it's somehow different.

Have you tried to test the database with sqlite3 database application?

Maarouf Med Mahdi

@karlheinzreichel
all queries it works well with SQLiteStudio and has the same database

Stoyan

@Maarouf-Med-Mahdi
I'm sure there is such database in correct path. But did you found another file with the same name in other directory?
Also, you should use '/' as directory separator:

Qt uses "/" as a universal directory separator in the same way that "/" is used as a path separator in URLs. If you always use "/" as a directory separator, Qt will translate your paths to conform to the underlying operating system.

Stoyan

@Maarouf-Med-Mahdi
With SQLiteStudio you are connecting to real database and everything works.
With Qt you are trying to connect to wrong database and new database file is created and connected. This database is empty and that's why there is no tables in it.
Execute this query with SQLiteStudio and with Qt and compare the results.

select * from sqlite_master where tbl_name = 'serveurs';

And how much files with name "GestionDataCenter_BD.db" did you found in your computer?

Maarouf Med Mahdi

I copied the same database (exported) and put it in the directory of my project. and I checked with notepade that all the tables are created, in the end I gave it to QT by the way of this last database

Maarouf Med Mahdi

@Stoyan that query
select * from sqlite_master where tbl_name = 'serveurs';
works in the both

Stoyan

@Maarouf-Med-Mahdi
It always works. The question is how many rows returns in each case.

Maarouf Med Mahdi

@Stoyan -1
QString text_req = "select * from sqlite_master where tbl_name='serveurs'";
if(requette.exec(text_req))
qDebug()<<"requette valide"<<requette.size();
else
qDebug()<<"invalide requette"<<" --> "<<requette.lastError().text();
connected
requette valide -1

Stoyan

@Maarouf-Med-Mahdi
Unfortunately, SQLite doesn't support QSqlQuery::size() function.
Instead you can use this:

if(requette.exec(text_req))
{
    requette.last();
    qDebug() << requette.at() + 1;
}

Maarouf Med Mahdi

@Stoyan that give me -1 again

Stoyan

@Maarouf-Med-Mahdi
You should just change directory separator in your code from "\" to "/".
I make some tests with this code:

    QSqlDatabase mydb = QSqlDatabase::addDatabase("QSQLITE");
    mydb.setDatabaseName("C:\Projects\Test\BD.db");
    if(!mydb.open())
    {
        qDebug() << mydb.lastError().text();
    }
    qDebug() << "Tables: " << mydb.tables();
    quint16 cnt = 0;
     QSqlQuery q;
     QString text_req = "select * from sqlite_master where tbl_name='serveurs'";
     if(q.exec(text_req))
     {
         while(q.next())
         {
             cnt++;
         }
         qDebug() << "Records count: " << cnt;
     }
     else
         qDebug()<<"Invalide query"<<" --> " << q.lastError().text();

On compile it give warnings:

warning: unknown escape sequence: '\P'
warning: unknown escape sequence: '\T'
warning: unknown escape sequence: '\B'

The result was this (just like yours):

Tables:  ()
Records count:  0

When I change this row:

    mydb.setDatabaseName("C:\Projects\Test\BD.db");

with this:

    mydb.setDatabaseName("C:/Projects/Test/BD.db");

there are no warnings, everything works and the result is:

Tables:  ("serveurs", "historiques")
Records count:  2

Maarouf Med Mahdi

Just I want to give my experience result or a advice about this and to don't repeate to other members.
Sometimes, Qt does not accept an absolute path of the database file if it is not in the
same output program file (Debug or Release).
If Qt can not recover your database file, it will create a new empty database in the same output program folder. this can make the not such table sql error .
I want to thank all the members they help me for finding my proposed solution.

SGaist

Hi,

That's unrelated to Qt. It's how SQLite behaves. If there's no file matching the parameter you give it, it will create it. What you can do is check the file existence with QFile.

Maarouf Med Mahdi

Hi @SGaist
Thanks for that SQLite information . I checked that .
all what i did to find that solution, i have moved the DataBase file to the output folder .