Debug Assertion

Davitor

Hi All I am geting debug assertion failed Line 3232 in file dbcore.cpp.Code is here

Database database;
try
{
if(database.OpenEx(_T("Driver={MySQL ODBC 5.1 Driver};Server=localhost;Database=;User=root; Password=root;Option=3;"), CDatabase::noOdbcDialog))
{
AfxMessageBox("Connection Successfully");

		CString szSql = "SHOW DATABASES";

CRecordset rs(&database);
rs.Open( CRecordset::forwardOnly, szSql);

while (!rs.IsEOF())
{
CString szBuf;

rs.GetFieldValue("DATABASE", szBuf);

rs.MoveNext();
}

rs.Close();

	}
}
catch(CException \*e)
{
AfxMessageBox("Connection Failed");	
}

i am geting assertion in this line

rs.Open( CRecordset::forwardOnly, szSql);
Debug assertion failed Line 3232 in file dbcore.cpp.

I see line 3232 in dbcore.cpp file.There i found this syntax

ASSERT(m_nFields != 0);

Can any one tell how can i solve that debug assertion. Plz help me

Madhu Nair 0

Use CDBException to catch the error in your database code

_Superman_

Your query didn't have any output fields. Probably something wrong with the query.

«_Superman_» I love work. It gives me something to do between weekends.

Davitor

Thanks for reply. I use CDBException class for catch the error.But it's showing same Assertion.

Davitor

Ok but same query i have check in mysql,then it's working fine.If you have any more query then plz give me.

CPallini

See if this [^] helps. :)

If the Lord God Almighty had consulted me before embarking upon the Creation, I would have recommended something simpler. -- Alfonso the Wise, 13th Century King of Castile.
This is going on my arrogant assumptions. You may have a superb reason why I'm completely wrong. -- Iain Clarke
[My articles]

Davitor

Hi CPallini Thanks for reply.may i know where is concept of my question in your post?Plz help me

CPallini

It looks like you've to change the flag "Ignore # in table name" in your ODBC driver in order to make the statement 'SHOW DATABASES' work. :)

If the Lord God Almighty had consulted me before embarking upon the Creation, I would have recommended something simpler. -- Alfonso the Wise, 13th Century King of Castile.
This is going on my arrogant assumptions. You may have a superb reason why I'm completely wrong. -- Iain Clarke
[My articles]

Davitor

So i change

CString szSql = "SHOW DATABASES"; to this
szSql = "SHOW DATABASES from mysql",

or

rs.Open( CRecordset::forwardOnly, szSql); to this
rs.Open( _T("Driver={MySQL ODBC 5.1 Driver};Server=localhost;Database=;User=root; Password=root;Option=3;"),szSql,CRecordset::forwardOnly);

Both are givesame debug assertion. Plz help me

Stuart Dootson

Ummmmm - "SHOW DATABASES" isn't SQL? It IS a MySQL command - but that doesn't necessarily make it something you can execute using ODBC?

Java, Basic, who cares - it's all a bunch of tree-hugging hippy cr*p

Davitor

yaa i know "SHOW DATABASE" is Mysql command and i am useing for MySql.Can you tell how and which command is execute for SHOW DATABASE useing ODBC? Plz help me

CPallini

You may try 'SHOW SCHEMA', it looks like more 'SQL standard'. :)

If the Lord God Almighty had consulted me before embarking upon the Creation, I would have recommended something simpler. -- Alfonso the Wise, 13th Century King of Castile.
This is going on my arrogant assumptions. You may have a superb reason why I'm completely wrong. -- Iain Clarke
[My articles]

Stuart Dootson

Don't think you can use CRecordset - I don't think it lets you execute arbitrary commands. You could use CDatabase::ExecuteSQL - but that doesn't return any results. You can use ODBC to execute that command - here's how you'd do it in Python

import dbi
import odbc
conn = odbc.odbc("Driver={MySQL ODBC 5.1 Driver}; Server=localhost; Database=; User=root; Password=password; Option=3;")
curs = conn.cursor()
curs.execute("SHOW DATABASES")
curs.fetchall()

results in something like this

[('information_schema',), ('mysql',), ('test',)]

Here's how you could do it in C++ with ADO:

#import "libid:2A75196C-D9EB-4129-B803-931327F72D5C" rename("EOF", "adoEOF")

int main()
{
CoInitialize(0);
ADODB::_ConnectionPtr conn(__uuidof(ADODB::Connection));
conn->Open(_bstr_t("Driver={MySQL ODBC 5.1 Driver}; Server=localhost; Database=; User=root; Password=password; Option=3;"), "", "", 0);
ADODB::_RecordsetPtr rs = conn->Execute(_bstr_t("SHOW DATABASES"), 0, ADODB::adCmdText);

_variant_t databaseNames = rs->GetRows(ADODB::adGetRowsRest);
}

databaseNames is a SAFEARRAY containing BSTR elements, one for each database name.

Last modified: 3hrs 14mins after originally posted --

Java, Basic, who cares - it's all a bunch of tree-hugging hippy cr*p

Davitor

Thanks

Davitor

Hi Stuart Dootson This things is working fine.But i need to use "Select * from Tablename".Show how can i get full information of table in

_variant_t.

Plz help me

Stuart Dootson

It's not too difficult to find[^] appropriate examples[^] on t'Internet.

Java, Basic, who cares - it's all a bunch of tree-hugging hippy cr*p