Qt Sql error coming from nowhere: No query Unable to fetch row
I have a client connected to a server, and it is also connected to a Sqlite3 database. When I receive a message from the server a get an QMessageBox showing an error
"No query Unable to fetch row"
I tried it with qDebug() outputs and by Debugging the application but the message is not produced by me nor thrown by any DB execution, since none is executed at the moment when I get the message.
Ok I figured out that the error is shown when I write something to the socket. The error does not affect anything, the program continues to run. Here is the code piece were the error is shown:
void ConnectionHandler::sendBytes(QByteArray bytes)
QMessageBox::critical(0, "test", "test");
this->socket->write(bytes);
this->socket->flush(); // after this call the error message is shown
this->socket->waitForBytesWritten();
QMessageBox::critical(0, "test2", "test2");
I checked the bytes that are supposed to be written but they look like what they are supposed to!?
Screenshot of the error:
qt
edited Nov 13 '18 at 6:25
Cœur
17.4k9103145
asked Oct 22 '15 at 6:42
wasp256wasp256
2,16743265
|
show 2 more comments
I have a client connected to a server, and it is also connected to a Sqlite3 database. When I receive a message from the server a get an QMessageBox showing an error
"No query Unable to fetch row"
I tried it with qDebug() outputs and by Debugging the application but the message is not produced by me nor thrown by any DB execution, since none is executed at the moment when I get the message.
Ok I figured out that the error is shown when I write something to the socket. The error does not affect anything, the program continues to run. Here is the code piece were the error is shown:
void ConnectionHandler::sendBytes(QByteArray bytes)
QMessageBox::critical(0, "test", "test");
this->socket->write(bytes);
this->socket->flush(); // after this call the error message is shown
this->socket->waitForBytesWritten();
QMessageBox::critical(0, "test2", "test2");
I checked the bytes that are supposed to be written but they look like what they are supposed to!?
Screenshot of the error:
qt
edited Nov 13 '18 at 6:25
Cœur
17.4k9103145
asked Oct 22 '15 at 6:42
wasp256wasp256
2,16743265
Maybe this helps you: QT5 and SQLite3 “No query Unable to fetch row”.
– agold
Oct 22 '15 at 7:14
As mentioned I get the error but there is no transaction to the database happening, no SELECT nor INSERT!?. I inserted a breakpoint in thereadyReadmethod and before it arrives on that breakpoint I receive the error message...
– wasp256
Oct 22 '15 at 7:18
Can you add some code and indicate where this error happens? And did you try a really simple program to connect to the database and do the query (i.e. without any external client connections, etc.)? Just to check that part is working.
– agold
Oct 22 '15 at 7:20
I have no idea where the error comes from otherwise this post wouldn't be necessary, so posting the entire code is not possible. I have a server running to which two clients are connected. Both cleints are connected to a Sqlite DB, but not to the same. When one client sends a message to the other client through the server then the receiver shows the message before thereadyReadmethod is even called.
– wasp256
Oct 22 '15 at 7:26
But where in your code is this specific message (No query Unable to fetch row) shown. TheQMessageBox::criticallines in yoursendBytesfunction obviously don't show this. The message it shows you should be sent by some function that does the query call (directly or indirectly), but this cannot be deduced from this code.
– agold
Oct 22 '15 at 13:13
|
show 2 more comments
I have a client connected to a server, and it is also connected to a Sqlite3 database. When I receive a message from the server a get an QMessageBox showing an error
"No query Unable to fetch row"
I tried it with qDebug() outputs and by Debugging the application but the message is not produced by me nor thrown by any DB execution, since none is executed at the moment when I get the message.
Ok I figured out that the error is shown when I write something to the socket. The error does not affect anything, the program continues to run. Here is the code piece were the error is shown:
void ConnectionHandler::sendBytes(QByteArray bytes)
QMessageBox::critical(0, "test", "test");
this->socket->write(bytes);
this->socket->flush(); // after this call the error message is shown
this->socket->waitForBytesWritten();
QMessageBox::critical(0, "test2", "test2");
I checked the bytes that are supposed to be written but they look like what they are supposed to!?
Screenshot of the error:
qt
edited Nov 13 '18 at 6:25
Cœur
17.4k9103145
asked Oct 22 '15 at 6:42
wasp256wasp256
2,16743265
I have a client connected to a server, and it is also connected to a Sqlite3 database. When I receive a message from the server a get an QMessageBox showing an error
"No query Unable to fetch row"
I tried it with qDebug() outputs and by Debugging the application but the message is not produced by me nor thrown by any DB execution, since none is executed at the moment when I get the message.
Ok I figured out that the error is shown when I write something to the socket. The error does not affect anything, the program continues to run. Here is the code piece were the error is shown:
void ConnectionHandler::sendBytes(QByteArray bytes)
QMessageBox::critical(0, "test", "test");
this->socket->write(bytes);
this->socket->flush(); // after this call the error message is shown
this->socket->waitForBytesWritten();
QMessageBox::critical(0, "test2", "test2");
I checked the bytes that are supposed to be written but they look like what they are supposed to!?
Screenshot of the error:
qt
qt
edited Nov 13 '18 at 6:25
Cœur
17.4k9103145
asked Oct 22 '15 at 6:42
wasp256wasp256
2,16743265
edited Nov 13 '18 at 6:25
Cœur
17.4k9103145
asked Oct 22 '15 at 6:42
wasp256wasp256
2,16743265
edited Nov 13 '18 at 6:25
Cœur
17.4k9103145
edited Nov 13 '18 at 6:25
Cœur
17.4k9103145
edited Nov 13 '18 at 6:25
Cœur
17.4k9103145
17.4k9103145
asked Oct 22 '15 at 6:42
wasp256wasp256
2,16743265
asked Oct 22 '15 at 6:42
wasp256wasp256
2,16743265
asked Oct 22 '15 at 6:42
wasp256wasp256
2,16743265
2,16743265
Maybe this helps you: QT5 and SQLite3 “No query Unable to fetch row”.
– agold
Oct 22 '15 at 7:14
As mentioned I get the error but there is no transaction to the database happening, no SELECT nor INSERT!?. I inserted a breakpoint in thereadyReadmethod and before it arrives on that breakpoint I receive the error message...
– wasp256
Oct 22 '15 at 7:18
Can you add some code and indicate where this error happens? And did you try a really simple program to connect to the database and do the query (i.e. without any external client connections, etc.)? Just to check that part is working.
– agold
Oct 22 '15 at 7:20
I have no idea where the error comes from otherwise this post wouldn't be necessary, so posting the entire code is not possible. I have a server running to which two clients are connected. Both cleints are connected to a Sqlite DB, but not to the same. When one client sends a message to the other client through the server then the receiver shows the message before thereadyReadmethod is even called.
– wasp256
Oct 22 '15 at 7:26
But where in your code is this specific message (No query Unable to fetch row) shown. TheQMessageBox::criticallines in yoursendBytesfunction obviously don't show this. The message it shows you should be sent by some function that does the query call (directly or indirectly), but this cannot be deduced from this code.
– agold
Oct 22 '15 at 13:13
|
show 2 more comments
Maybe this helps you: QT5 and SQLite3 “No query Unable to fetch row”.
– agold
Oct 22 '15 at 7:14
As mentioned I get the error but there is no transaction to the database happening, no SELECT nor INSERT!?. I inserted a breakpoint in thereadyReadmethod and before it arrives on that breakpoint I receive the error message...
– wasp256
Oct 22 '15 at 7:18
Can you add some code and indicate where this error happens? And did you try a really simple program to connect to the database and do the query (i.e. without any external client connections, etc.)? Just to check that part is working.
– agold
Oct 22 '15 at 7:20
I have no idea where the error comes from otherwise this post wouldn't be necessary, so posting the entire code is not possible. I have a server running to which two clients are connected. Both cleints are connected to a Sqlite DB, but not to the same. When one client sends a message to the other client through the server then the receiver shows the message before thereadyReadmethod is even called.
– wasp256
Oct 22 '15 at 7:26
But where in your code is this specific message (No query Unable to fetch row) shown. TheQMessageBox::criticallines in yoursendBytesfunction obviously don't show this. The message it shows you should be sent by some function that does the query call (directly or indirectly), but this cannot be deduced from this code.
– agold
Oct 22 '15 at 13:13
Maybe this helps you: QT5 and SQLite3 “No query Unable to fetch row”.
– agold
Oct 22 '15 at 7:14
Maybe this helps you: QT5 and SQLite3 “No query Unable to fetch row”.
– agold
Oct 22 '15 at 7:14
As mentioned I get the error but there is no transaction to the database happening, no SELECT nor INSERT!?. I inserted a breakpoint in the
readyRead method and before it arrives on that breakpoint I receive the error message...– wasp256
Oct 22 '15 at 7:18
As mentioned I get the error but there is no transaction to the database happening, no SELECT nor INSERT!?. I inserted a breakpoint in the
readyRead method and before it arrives on that breakpoint I receive the error message...– wasp256
Oct 22 '15 at 7:18
Can you add some code and indicate where this error happens? And did you try a really simple program to connect to the database and do the query (i.e. without any external client connections, etc.)? Just to check that part is working.
– agold
Oct 22 '15 at 7:20
Can you add some code and indicate where this error happens? And did you try a really simple program to connect to the database and do the query (i.e. without any external client connections, etc.)? Just to check that part is working.
– agold
Oct 22 '15 at 7:20
I have no idea where the error comes from otherwise this post wouldn't be necessary, so posting the entire code is not possible. I have a server running to which two clients are connected. Both cleints are connected to a Sqlite DB, but not to the same. When one client sends a message to the other client through the server then the receiver shows the message before the
readyRead method is even called.– wasp256
Oct 22 '15 at 7:26
I have no idea where the error comes from otherwise this post wouldn't be necessary, so posting the entire code is not possible. I have a server running to which two clients are connected. Both cleints are connected to a Sqlite DB, but not to the same. When one client sends a message to the other client through the server then the receiver shows the message before the
readyRead method is even called.– wasp256
Oct 22 '15 at 7:26
But where in your code is this specific message (No query Unable to fetch row) shown. The
QMessageBox::critical lines in your sendBytes function obviously don't show this. The message it shows you should be sent by some function that does the query call (directly or indirectly), but this cannot be deduced from this code.– agold
Oct 22 '15 at 13:13
But where in your code is this specific message (No query Unable to fetch row) shown. The
QMessageBox::critical lines in your sendBytes function obviously don't show this. The message it shows you should be sent by some function that does the query call (directly or indirectly), but this cannot be deduced from this code.– agold
Oct 22 '15 at 13:13
|
show 2 more comments
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Maybe this helps you: QT5 and SQLite3 “No query Unable to fetch row”.
– agold
Oct 22 '15 at 7:14
As mentioned I get the error but there is no transaction to the database happening, no SELECT nor INSERT!?. I inserted a breakpoint in the
readyReadmethod and before it arrives on that breakpoint I receive the error message...– wasp256
Oct 22 '15 at 7:18
Can you add some code and indicate where this error happens? And did you try a really simple program to connect to the database and do the query (i.e. without any external client connections, etc.)? Just to check that part is working.
– agold
Oct 22 '15 at 7:20
I have no idea where the error comes from otherwise this post wouldn't be necessary, so posting the entire code is not possible. I have a server running to which two clients are connected. Both cleints are connected to a Sqlite DB, but not to the same. When one client sends a message to the other client through the server then the receiver shows the message before the
readyReadmethod is even called.– wasp256
Oct 22 '15 at 7:26
But where in your code is this specific message (No query Unable to fetch row) shown. The
QMessageBox::criticallines in yoursendBytesfunction obviously don't show this. The message it shows you should be sent by some function that does the query call (directly or indirectly), but this cannot be deduced from this code.– agold
Oct 22 '15 at 13:13