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/*-------------------------------------------------------------------------
*
* FILE
* pgconnection.cc
*
* DESCRIPTION
* implementation of the PgConnection class.
* PgConnection encapsulates a frontend to backend connection
*
* Copyright (c) 1994, Regents of the University of California
*
* IDENTIFICATION
* $Header: /cvsroot/pgsql/src/interfaces/libpq++/Attic/pgconnection.cc,v 1.10 2000/07/27 19:44:01 momjian Exp $
*
*-------------------------------------------------------------------------
*/
#include "pgconnection.h"
// ****************************************************************
//
// PgConnection Implementation
//
// ****************************************************************
// default constructor -- initialize everything
PgConnection::PgConnection()
: pgConn(NULL), pgResult(NULL), pgCloseConnection(0)
{}
// constructor -- checks environment variable for database name
// Now uses PQconnectdb
PgConnection::PgConnection(const char* conninfo)
: pgConn(NULL), pgResult(NULL), pgCloseConnection(1)
{
// Connect to the database
Connect( conninfo );
}
// destructor - closes down the connection and cleanup
PgConnection::~PgConnection()
{
// Close the connection only if needed
// This feature will most probably be used by the derived classes that
// need not close the connection after they are destructed.
CloseConnection();
}
// PgConnection::CloseConnection()
// close down the connection if there is one
void PgConnection::CloseConnection()
{
// if the connection is open, close it first
if ( pgCloseConnection ) {
if(pgResult) PQclear(pgResult);
pgResult=NULL;
if(pgConn) PQfinish(pgConn);
pgConn=NULL;
pgCloseConnection=0;
}
}
// PgConnection::connect
// establish a connection to a backend
ConnStatusType PgConnection::Connect(const char* conninfo)
{
// if the connection is open, close it first
CloseConnection();
// Connect to the database
pgConn = PQconnectdb(conninfo);
// Now we have a connection we must close (even if it's bad!)
pgCloseConnection = 1;
// Status will return either CONNECTION_OK or CONNECTION_BAD
return Status();
}
// PgConnection::status -- return connection or result status
ConnStatusType PgConnection::Status()
{
return PQstatus(pgConn);
}
// PgConnection::exec -- send a query to the backend
ExecStatusType PgConnection::Exec(const char* query)
{
// Clear the Result Stucture if needed
if (pgResult)
PQclear(pgResult);
// Execute the given query
pgResult = PQexec(pgConn, query);
// Return the status
if (pgResult)
return PQresultStatus(pgResult);
else
return PGRES_FATAL_ERROR;
}
// Return true if the Postgres command was executed OK
int PgConnection::ExecCommandOk(const char* query)
{
return Exec(query) == PGRES_COMMAND_OK;
} // End ExecCommandOk()
int PgConnection::ExecTuplesOk(const char* query)
{
return Exec(query) == PGRES_TUPLES_OK;
} // End ExecTuplesOk()
// Don't know why these next two need to be part of Connection
// PgConnection::notifies() -- returns a notification from a list of unhandled notifications
PGnotify* PgConnection::Notifies()
{
Exec(" ");
return PQnotifies(pgConn);
}
// From Integer To String Conversion Function
string PgConnection::IntToString(int n)
{
char buffer [32];
memset(buffer, 0, sizeof(buffer));
sprintf(buffer, "%d", n);
return buffer;
}
int PgConnection::ConnectionBad()
{
return Status() == CONNECTION_BAD;
}
const char* PgConnection::ErrorMessage()
{
return (const char *)PQerrorMessage(pgConn);
}
const char* PgConnection::DBName()
{
return (const char *)PQdb(pgConn);
}
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