ogrpgdatasource.cpp

GIS系统支持库Geospatial Data Abstraction Library代码.GDAL is a translator library for raster geospatial dat

/******************************************************************************
 * $Id: ogrpgdatasource.cpp,v 1.30 2005/03/04 21:04:06 fwarmerdam Exp $
 *
 * Project:  OpenGIS Simple Features Reference Implementation
 * Purpose:  Implements OGRPGDataSource class.
 * Author:   Frank Warmerdam, [e-mail]
 *
 ******************************************************************************
 * Copyright (c) 2000, Frank Warmerdam
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included
 * in all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
 * DEALINGS IN THE SOFTWARE.
 ******************************************************************************
 *
 * $Log: ogrpgdatasource.cpp,v $
 * Revision 1.30  2005/03/04 21:04:06  fwarmerdam
 * Added setting of dimension based on geometry type, or DIM override.
 *
 * Revision 1.29  2004/07/10 04:45:52  warmerda
 * more rigerous soft transaction handling
 *
 * Revision 1.28  2004/07/09 07:05:37  warmerda
 * Added OGRSQL dialect support.
 *
 * Revision 1.27  2004/04/30 18:30:05  warmerda
 * Fixed pszLayerName typo.
 *
 * Revision 1.26  2004/04/30 17:52:42  warmerda
 * added layer name laundering
 *
 * Revision 1.25  2004/04/30 15:17:38  warmerda
 * Added DELLAYER:layername ExecuteSQL() pseudo-directive.
 * Clean stale entries in geometry_columns table when creating a layer.
 *
 * Revision 1.24  2004/04/30 00:45:45  warmerda
 * default to launder being on
 *
 * Revision 1.23  2004/04/28 12:45:46  warmerda
 * Fixed screwup in table selection query.
 *
 * Revision 1.22  2004/04/23 15:10:10  warmerda
 * Added support for enumerating views.
 *
 * Revision 1.21  2004/04/02 17:44:55  warmerda
 * SELECT in caps for readability
 *
 * Revision 1.20  2004/01/19 18:48:11  warmerda
 * added commit after DROP TABLE and before dropping sequence
 *
 * Revision 1.19  2003/09/11 20:03:03  warmerda
 * initialize poSRS ariable in FetchSRS
 *
 * Revision 1.18  2003/05/21 03:59:42  warmerda
 * expand tabs
 *
 * Revision 1.17  2002/12/12 14:28:35  warmerda
 * fixed bug in DeleteLayer
 *
 * Revision 1.16  2002/10/20 03:45:27  warmerda
 * added debug on table create command
 *
 * Revision 1.15  2002/10/09 18:30:10  warmerda
 * substantial upgrade to type handling, and preservations of width/precision
 *
 * Revision 1.14  2002/10/04 14:03:09  warmerda
 * added column name laundering support
 *
 * Revision 1.13  2002/05/09 16:48:08  warmerda
 * upgrade to quote table and field names
 *
 * Revision 1.12  2002/05/09 16:03:19  warmerda
 * major upgrade to support SRS better and add ExecuteSQL
 *
 * Revision 1.11  2002/03/01 20:42:00  warmerda
 * fixed parsing of connect string, see bug 107
 *
 * Revision 1.10  2002/01/13 21:48:32  warmerda
 * fixed addgeometrycolumn call to include pszDBname
 *
 * Revision 1.9  2002/01/13 16:23:16  warmerda
 * capture dbname= parameter for use in AddGeometryColumn() call
 *
 * Revision 1.8  2001/11/15 21:19:58  warmerda
 * added soft transaction semantics
 *
 * Revision 1.7  2001/09/28 04:03:52  warmerda
 * partially upraded to PostGIS 0.6
 *
 * Revision 1.6  2001/07/18 04:55:16  warmerda
 * added CPL_CSVID
 *
 * Revision 1.5  2001/06/26 20:59:13  warmerda
 * implement efficient spatial and attribute query support
 *
 * Revision 1.4  2001/06/20 16:10:24  warmerda
 * fixed PostGIS autodetect
 *
 * Revision 1.3  2001/06/19 22:29:12  warmerda
 * upgraded to include PostGIS support
 *
 * Revision 1.2  2000/11/23 06:03:35  warmerda
 * added Oid support
 *
 * Revision 1.1  2000/10/17 17:46:51  warmerda
 * New
 *
 */

#include "ogr_pg.h"
#include "cpl_conv.h"
#include "cpl_string.h"

CPL_CVSID("$Id: ogrpgdatasource.cpp,v 1.30 2005/03/04 21:04:06 fwarmerdam Exp $");

static void OGRPGNoticeProcessor( void *arg, const char * pszMessage );

/************************************************************************/
/*                          OGRPGDataSource()                           */
/************************************************************************/

OGRPGDataSource::OGRPGDataSource()

{
    pszName = NULL;
    pszDBName = NULL;
    papoLayers = NULL;
    nLayers = 0;
    hPGConn = NULL;
    bHavePostGIS = FALSE;
    nSoftTransactionLevel = 0;

    nKnownSRID = 0;
    panSRID = NULL;
    papoSRS = NULL;
}

/************************************************************************/
/*                          ~OGRPGDataSource()                          */
/************************************************************************/

OGRPGDataSource::~OGRPGDataSource()

{
    int         i;

    FlushSoftTransaction();

    CPLFree( pszName );
    CPLFree( pszDBName );

    for( i = 0; i < nLayers; i++ )
        delete papoLayers[i];
    
    CPLFree( papoLayers );

    if( hPGConn != NULL )
        PQfinish( hPGConn );

    for( i = 0; i < nKnownSRID; i++ )
    {
        if( papoSRS[i] != NULL && papoSRS[i]->Dereference() == 0 )
            delete papoSRS[i];
    }
    CPLFree( panSRID );
    CPLFree( papoSRS );
}

/************************************************************************/
/*                                Open()                                */
/************************************************************************/

int OGRPGDataSource::Open( const char * pszNewName, int bUpdate,
                              int bTestOpen )

{
    CPLAssert( nLayers == 0 );

/* -------------------------------------------------------------------- */
/*      Verify postgresql prefix.                                       */
/* -------------------------------------------------------------------- */
    if( !EQUALN(pszNewName,"PG:",3) )
    {
        if( !bTestOpen )
            CPLError( CE_Failure, CPLE_AppDefined, 
                      "%s does not conform to PostgreSQL naming convention,"
                      " PG:*\n" );
        return FALSE;
    }
    
/* -------------------------------------------------------------------- */
/*      Try to establish connection.                                    */
/* -------------------------------------------------------------------- */
    hPGConn = PQconnectdb( pszNewName + 3 );
    if( hPGConn == NULL || PQstatus(hPGConn) == CONNECTION_BAD )
    {
        CPLError( CE_Failure, CPLE_AppDefined, 
                  "PGconnectcb failed.\n%s", 
                  PQerrorMessage(hPGConn) );
        PQfinish(hPGConn);
        hPGConn = NULL;
        return FALSE;
    }

    pszName = CPLStrdup( pszNewName );
    
    bDSUpdate = bUpdate;

/* -------------------------------------------------------------------- */
/*      Install a notice processor.                                     */
/* -------------------------------------------------------------------- */
    PQsetNoticeProcessor( hPGConn, OGRPGNoticeProcessor, this );

/* -------------------------------------------------------------------- */
/*      Try to establish the database name from the connection          */
/*      string passed.                                                  */
/* -------------------------------------------------------------------- */
    if( strstr(pszNewName, "dbname=") != NULL )
    {
        int     i;

        pszDBName = CPLStrdup( strstr(pszNewName, "dbname=") + 7 );

        for( i = 0; pszDBName[i] != '\0'; i++ )
        {
            if( pszDBName[i] == ' ' )                                   
            {
                pszDBName[i] = '\0';
                break;
            }
        }
    }
    else if( getenv( "USER" ) != NULL )
        pszDBName = CPLStrdup( getenv("USER") );
    else
        pszDBName = CPLStrdup( "unknown_dbname" );
        
    CPLDebug( "OGR_PG", "DBName=\"%s\"", pszDBName );

/* -------------------------------------------------------------------- */
/*      Test to see if this database instance has support for the       */
/*      PostGIS Geometry type.  If so, disable sequential scanning      */
/*      so we will get the value of the gist indexes.                   */
/* -------------------------------------------------------------------- */
    PGresult            *hResult;
    
    hResult = PQexec(hPGConn, "BEGIN");

    if( hResult && PQresultStatus(hResult) == PGRES_COMMAND_OK )
    {
        PQclear( hResult );

        hResult = PQexec(hPGConn, 
                         "SELECT oid FROM pg_type WHERE typname = 'geometry'" );
    }

    if( hResult && PQresultStatus(hResult) == PGRES_TUPLES_OK 
        && PQntuples(hResult) > 0 )
    {
        bHavePostGIS = TRUE;
        nGeometryOID = atoi(PQgetvalue(hResult,0,0));
    }
    else
        nGeometryOID = (Oid) 0;

    if( hResult )
        PQclear( hResult );

    hResult = PQexec(hPGConn, "SET ENABLE_SEQSCAN = OFF");
    PQclear( hResult );

    hResult = PQexec(hPGConn, "COMMIT");
    PQclear( hResult );

/* -------------------------------------------------------------------- */
/*      Get a list of available tables.                                 */
/* -------------------------------------------------------------------- */
    hResult = PQexec(hPGConn, "BEGIN");

    if( hResult && PQresultStatus(hResult) == PGRES_COMMAND_OK )
    {
        PQclear( hResult );

        hResult = PQexec(hPGConn, 
                         "DECLARE mycursor CURSOR for "
                         "SELECT relname FROM pg_class "
                         "WHERE (relkind in ('r','v') AND relname !~ '^pg')" );
    }

    if( hResult && PQresultStatus(hResult) == PGRES_COMMAND_OK )
    {
        PQclear( hResult );
        hResult = PQexec(hPGConn, "FETCH ALL in mycursor" );
    }

    if( !hResult || PQresultStatus(hResult) != PGRES_TUPLES_OK )
    {
        CPLError( CE_Failure, CPLE_AppDefined, 
                  "%s", PQerrorMessage(hPGConn) );
        return FALSE;
    }

/* -------------------------------------------------------------------- */
/*      Parse the returned table list                                   */
/* -------------------------------------------------------------------- */
    char        **papszTableNames=NULL;
    int           iRecord;

    for( iRecord = 0; iRecord < PQntuples(hResult); iRecord++ )
    {
        const char *pszTable = PQgetvalue(hResult, iRecord, 0);

        if( EQUAL(pszTable,"spatial_ref_sys")
            || EQUAL(pszTable,"geometry_columns") )
            continue;

        papszTableNames = CSLAddString(papszTableNames, 
                                       PQgetvalue(hResult, iRecord, 0));
    }

/* -------------------------------------------------------------------- */
/*      Cleanup                                                         */
/* -------------------------------------------------------------------- */
    PQclear( hResult );

    hResult = PQexec(hPGConn, "CLOSE mycursor");
    PQclear( hResult );

    hResult = PQexec(hPGConn, "COMMIT");
    PQclear( hResult );

/* -------------------------------------------------------------------- */
/*      Get the schema of the available tables.                         */
/* -------------------------------------------------------------------- */
    for( iRecord = 0; 
         papszTableNames != NULL && papszTableNames[iRecord] != NULL;
         iRecord++ )
    {
        OpenTable( papszTableNames[iRecord], bUpdate, FALSE );
    }

    CSLDestroy( papszTableNames );
    
    return nLayers > 0 || bUpdate;
}

/************************************************************************/
/*                             OpenTable()                              */
/************************************************************************/

int OGRPGDataSource::OpenTable( const char *pszNewName, int bUpdate,
                                int bTestOpen )

{
/* -------------------------------------------------------------------- */
/*      Create the layer object.                                        */
/* -------------------------------------------------------------------- */
    OGRPGLayer  *poLayer;

    poLayer = new OGRPGTableLayer( this, pszNewName, bUpdate );

/* -------------------------------------------------------------------- */
/*      Add layer to data source layer list.                            */
/* -------------------------------------------------------------------- */
    papoLayers = (OGRPGLayer **)
        CPLRealloc( papoLayers,  sizeof(OGRPGLayer *) * (nLayers+1) );
    papoLayers[nLayers++] = poLayer;
    
    return TRUE;
}

/************************************************************************/