Re: ADODB Command memory leak

I suspect you have a pointer leak in your code. It is quite easy to do in
C++, as we all know. (G)

Following code I just wrote works for me, no leaks ->

// START SAMPLE
// JetParam.cpp : Defines the entry point for the console application.
//

#include <windows.h>
#include <conio.h>
#include <stdio.h>

#undef EOF
#import <msado15.dll> no_namespace // Add full path to msado15.dll to vc++
include path.

_bstr_t JET_CONNECT(L"Provider=Microsoft.Jet.OLEDB.4.0;Data
Source=C:\\NW99.mdb;");
#define LOOP_COUNT 100000 // Number of loops to execute.

_ConnectionPtr GetJetConnection()
{
HRESULT hr;
_ConnectionPtr conn = NULL;

hr = conn.CreateInstance( __uuidof(Connection) );
//if ( FAILED( hr ) ) throw( _com_error( hr, NULL ) );

conn->CursorLocation = adUseServer;

// Open connection.
conn->Open( JET_CONNECT, "", "", -1L );

return conn;

}

void main(void)
{
HRESULT hr;
_ConnectionPtr global_conn = NULL;
_ConnectionPtr conn = NULL;
_CommandPtr cmd = NULL;
BOOL fCreateTestTable = TRUE;
int i;
CoInitialize(NULL);

try
{
// Open global conn to keep Jet loaded (perf).
global_conn = GetJetConnection();

for (i=1; i<=LOOP_COUNT; i++ )
{
// Open local conn for loop.
conn = GetJetConnection();

if ( fCreateTestTable )
{
try
{
conn->Execute(L"drop table T1",NULL,adExecuteNoRecords|adCmdText);
}
catch ( _com_error ex )
{

}

conn->Execute(L"create table T1(f1 int, f2
text(255))",NULL,adExecuteNoRecords|adCmdText);
fCreateTestTable = FALSE;
}

// Now create parameterized ADO call.
hr = cmd.CreateInstance( __uuidof(Command) );
if ( FAILED( hr ) ) throw( _com_error( hr, NULL ) );

cmd->ActiveConnection = conn;

// Create insert statement and setup params.
cmd->CommandText = L"insert into T1 (f1,f2) values (?,?)";
cmd->CommandType = adCmdText;

cmd->Parameters->Append(cmd->CreateParameter(
L"p1",adInteger,adParamInput,0));
cmd->Parameters->Append(cmd->CreateParameter(
L"p2",adVarChar,adParamInput,255));

cmd->Parameters->Item[0L]->Value = 1L;
cmd->Parameters->Item[1L]->Value = L"This is a test";

// Execute statement.
cmd->Execute(NULL,NULL,adExecuteNoRecords);

// Cleanup
cmd->ActiveConnection = NULL;
cmd = NULL;
conn->Close();
conn = NULL;

if ( 0 == (i%1000))
{
printf( "Completed %08lu of %08lu iterations.\n", i, LOOP_COUNT );
}
}

}
catch( _com_error ex )
{
// Robust error trapping left as an exercise for the reader. (G)
printf( "_com_error=%S\n" );
}
return;
}
// END SAMPLE


Matt Neerincx [MSFT]

This posting is provided "AS IS", with no warranties, and confers no rights.

Please do not send email directly to this alias. This alias is for newsgroup
purposes only.

"khalprin" <khalprin@xxxxxxxxxxxxxxxxxxxxxxxxx> wrote in message
news:88157683-9E86-44B2-B65E-6C040A959E72@xxxxxxxxxxxxxxxx
> My logic is such that the connection to the database is not maintained
> between calls to the Execute() method. Sorry I didn't mention that
> before.
> My test involves these steps:
>
> 1. Create the connection object
> 2. Connect to the database
> 3. Create the command object
> 4. Create/Append command parameters
> 5. Execute the command
> 6. Destroy the command object
> 7. Close database connection
> 8. Go to step 2 for xxxx iterations
> 9. Destroy the connection object.
>
> Thanks.
>
>
> "Val Mazur (MVP)" wrote:
>
>> Hi,
>>
>>
>> See if it does not help
>>
>> http://support.microsoft.com/default.aspx?scid=kb;en-us;248014
>>
>> --
>> Val Mazur
>> Microsoft MVP
>>
>> http://xport.mvps.org
>>
>>
>>
>> "khalprin" <khalprin@xxxxxxxxxxxxxxxxxxxxxxxxx> wrote in message
>> news:ACD0680A-59E1-4179-BEA8-1AFF685C6441@xxxxxxxxxxxxxxxx
>> > Hello,
>> >
>> > I'm tracking down a memory leak and have narrowed it down to the single
>> > line
>> > of my code that calls the Execute() method of the ADODB Command object.
>> >
>> > In this case, the Execute() is executing a query (that takes 2
>> > parameters)
>> > in MS Access that inserts 3 records into a table. I'm using the
>> > command
>> > 'adCmdStoredProc' with the flag 'adExecuteNoRecords'. The command
>> > executes
>> > successfully and does not return a recordset pointer.
>> >
>> > When I run this through 1000s of iterations for my test, memory usage
>> > grows
>> > continuously. If I comment out the Execute() call, memory usage does
>> > not
>> > grow.
>> >
>> > The command is setup as follows:
>> >
>> > pCmd->put_ActiveConnection(*pConn); // variant
>> > pCmd->CommandText = szQuery; // name of query/stored proc
>> > pCmd->CommandType = cmd; // ADODB command id
>> >
>> > The actual line of code that executes the command is:
>> >
>> > pCmd->Execute(NULL, NULL, cmd | ADODB::adExecuteNoRecords);
>> >
>> >
>> > Any ideas?
>> >
>>
>>
>>


.

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