ogrpgtablelayer.cpp

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

/******************************************************************************
 * $Id: ogrpgtablelayer.cpp,v 1.25 2005/02/22 12:54:05 fwarmerdam Exp $
 *
 * Project:  OpenGIS Simple Features Reference Implementation
 * Purpose:  Implements OGRPGTableLayer class, access to an existing table.
 * 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: ogrpgtablelayer.cpp,v $
 * Revision 1.25  2005/02/22 12:54:05  fwarmerdam
 * use OGRLayer base spatial filter support
 *
 * Revision 1.24  2005/02/11 22:17:10  fwarmerdam
 * Applied fix for bug 681.  The truncation logic was kicking
 * inappropriately for integerlist and stringlist values.
 *
 * Revision 1.23  2004/11/17 17:49:27  fwarmerdam
 * implemented SetFeature and DeleteFeature methods
 *
 * Revision 1.22  2004/09/16 18:24:47  fwarmerdam
 * fixed trimming code, just truncate long text
 *
 * Revision 1.21  2004/07/10 04:47:40  warmerda
 * Ensure that setting a NULL (or empty) query reset pszQuery to NULL.
 * Use soft transactions more carefully.
 * Ensure that rings are closed on polygons.
 *
 * Revision 1.20  2004/07/09 18:36:14  warmerda
 * Fixed last fix ... put the varchar stuff in side quotes and didn't
 * address the case with no length set.
 *
 * Revision 1.19  2004/07/09 16:34:23  warmerda
 * Added patch from Markus to trim strings to allowed length.
 *
 * Revision 1.18  2004/05/08 02:14:49  warmerda
 * added GetFeature() on table, generalize FID support a bit
 *
 * Revision 1.17  2004/04/30 17:52:42  warmerda
 * added layer name laundering
 *
 * Revision 1.16  2004/04/30 00:47:31  warmerda
 * launder field name oid to oid_
 *
 * Revision 1.15  2004/03/17 06:53:28  warmerda
 * Make command string arbitrary length in BuildFullQueryStatement() as
 * per report from Stephen Frost.
 *
 * Revision 1.14  2003/09/11 20:03:36  warmerda
 * avoid warning
 *
 * Revision 1.13  2003/05/21 03:59:42  warmerda
 * expand tabs
 *
 * Revision 1.12  2003/02/01 07:55:48  warmerda
 * avoid dependence on libpq-fs.h
 *
 * Revision 1.11  2003/01/08 22:07:14  warmerda
 * Added support for integer and real list field types
 *
 * Revision 1.10  2002/12/12 14:29:28  warmerda
 * fixed bug with creating features with no geometry in PostGIS
 *
 * Revision 1.9  2002/10/20 03:45:53  warmerda
 * quote table name in feature insert, and feature count commands
 *
 * Revision 1.8  2002/10/09 18:30:10  warmerda
 * substantial upgrade to type handling, and preservations of width/precision
 *
 * Revision 1.7  2002/10/09 14:16:32  warmerda
 * changed the way that character field widths are extracted from catalog
 *
 * Revision 1.6  2002/10/04 14:03:09  warmerda
 * added column name laundering support
 *
 * Revision 1.5  2002/09/19 17:40:42  warmerda
 * Make initial ResetReading() call to set full query expression in constructor.
 *
 * Revision 1.4  2002/05/09 17:21:54  warmerda
 * Don't add trailing command if no fields to be inserted.
 *
 * Revision 1.3  2002/05/09 17:09:08  warmerda
 * Ensure nSRSId is set before creating any features.
 *
 * Revision 1.2  2002/05/09 16:48:08  warmerda
 * upgrade to quote table and field names
 *
 * Revision 1.1  2002/05/09 16:03:46  warmerda
 * New
 *
 */

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

CPL_CVSID("$Id: ogrpgtablelayer.cpp,v 1.25 2005/02/22 12:54:05 fwarmerdam Exp $");

#define CURSOR_PAGE     1

/************************************************************************/
/*                          OGRPGTableLayer()                           */
/************************************************************************/

OGRPGTableLayer::OGRPGTableLayer( OGRPGDataSource *poDSIn, 
                                  const char * pszTableName,
                                  int bUpdate, int nSRSIdIn )

{
    poDS = poDSIn;

    pszQuery = NULL;
    pszWHERE = CPLStrdup( "" );
    pszQueryStatement = NULL;
    
    bUpdateAccess = bUpdate;

    iNextShapeId = 0;

    nSRSId = nSRSIdIn;

    poFeatureDefn = ReadTableDefinition( pszTableName );
    
    ResetReading();

    bLaunderColumnNames = TRUE;
}

/************************************************************************/
/*                          ~OGRPGTableLayer()                          */
/************************************************************************/

OGRPGTableLayer::~OGRPGTableLayer()

{
    CPLFree( pszQuery );
    CPLFree( pszWHERE );
}

/************************************************************************/
/*                        ReadTableDefinition()                         */
/*                                                                      */
/*      Build a schema from the named table.  Done by querying the      */
/*      catalog.                                                        */
/************************************************************************/

OGRFeatureDefn *OGRPGTableLayer::ReadTableDefinition( const char * pszTable )

{
    PGresult            *hResult;
    char                szCommand[1024];
    PGconn              *hPGConn = poDS->GetPGConn();
    
/* -------------------------------------------------------------------- */
/*      Fire off commands to get back the schema of the table.          */
/* -------------------------------------------------------------------- */
    poDS->FlushSoftTransaction();
    hResult = PQexec(hPGConn, "BEGIN");

    if( hResult && PQresultStatus(hResult) == PGRES_COMMAND_OK )
    {
        PQclear( hResult );
        sprintf( szCommand, 
                 "DECLARE mycursor CURSOR for "
                 "SELECT a.attname, t.typname, a.attlen,"
                 "       format_type(a.atttypid,a.atttypmod) "
                 "FROM pg_class c, pg_attribute a, pg_type t "
                 "WHERE c.relname = '%s' "
                 "AND a.attnum > 0 AND a.attrelid = c.oid "
                 "AND a.atttypid = t.oid", 
                 pszTable );

        hResult = PQexec(hPGConn, szCommand );
    }

    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 NULL;
    }

/* -------------------------------------------------------------------- */
/*      Parse the returned table information.                           */
/* -------------------------------------------------------------------- */
    OGRFeatureDefn *poDefn = new OGRFeatureDefn( pszTable );
    int            iRecord;

    for( iRecord = 0; iRecord < PQntuples(hResult); iRecord++ )
    {
        const char      *pszType, *pszFormatType;
        OGRFieldDefn    oField( PQgetvalue( hResult, iRecord, 0 ), OFTString);

        pszType = PQgetvalue(hResult, iRecord, 1 );
        pszFormatType = PQgetvalue(hResult,iRecord,3);

        /* TODO: Add detection of other primary key to use as FID */
        if( EQUAL(oField.GetNameRef(),"ogc_fid") )
        {
            bHasFid = TRUE;
            pszFIDColumn = CPLStrdup(oField.GetNameRef());
            continue;
        }
        else if( EQUAL(pszType,"geometry") )
        {
            bHasPostGISGeometry = TRUE;
            pszGeomColumn = CPLStrdup( oField.GetNameRef());
            continue;
        }
        else if( EQUAL(oField.GetNameRef(),"WKB_GEOMETRY") )
        {
            bHasWkb = TRUE;
            if( EQUAL(pszType,"OID") )
                bWkbAsOid = TRUE;
            continue;
        }

        if( EQUAL(pszType,"varchar") || EQUAL(pszType,"text") )
        {
            oField.SetType( OFTString );
        }
        else if( EQUAL(pszType,"bpchar") )
        {
            int nWidth;

            nWidth = atoi(PQgetvalue(hResult,iRecord,2));
            if( nWidth == -1 )
            {
                if( EQUALN(pszFormatType,"character(",10) )
                    nWidth = atoi(pszFormatType+10);
                else
                    nWidth = 0;
            }
            oField.SetType( OFTString );
            oField.SetWidth( nWidth );
        }
        else if( EQUAL(pszType,"numeric") )
        {
            const char *pszFormatName = PQgetvalue(hResult,iRecord,3);
            const char *pszPrecision = strstr(pszFormatName,",");
            int    nWidth, nPrecision = 0;

            nWidth = atoi(pszFormatName + 8);
            if( pszPrecision != NULL )
                nPrecision = atoi(pszPrecision+1);
            
            if( nPrecision == 0 )
                oField.SetType( OFTInteger );
            else
                oField.SetType( OFTReal );

            oField.SetWidth( nWidth );
            oField.SetPrecision( nPrecision );
        }
        else if( EQUAL(pszFormatType,"integer[]") )
        {
            oField.SetType( OFTIntegerList );
        }
        else if( EQUAL(pszFormatType,"float[]") )
        {
            oField.SetType( OFTRealList );
        }
        else if( EQUAL(pszType,"int2") )
        {
            oField.SetType( OFTInteger );
            oField.SetWidth( 5 );
        }
        else if( EQUALN(pszType,"int",3) )
        {
            oField.SetType( OFTInteger );
        }
        else if( EQUALN(pszType,"float",5) || EQUALN(pszType,"double",6) )
        {
            oField.SetType( OFTReal );
        }
        else if( EQUAL(pszType, "date") ) 
        {
            oField.SetType( OFTString );
            oField.SetWidth( 10 );
        }
        else if( EQUAL(pszType, "time") ) 
        {
            oField.SetType( OFTString );
            oField.SetWidth( 8 );
        }
        
        poDefn->AddFieldDefn( &oField );
    }

    PQclear( hResult );

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

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

    return poDefn;
}

/************************************************************************/
/*                          SetSpatialFilter()                          */
/************************************************************************/

void OGRPGTableLayer::SetSpatialFilter( OGRGeometry * poGeomIn )

{
    if( !InstallFilter( poGeomIn ) )
        return;

    BuildWhere();

    ResetReading();
}

/************************************************************************/
/*                             BuildWhere()                             */
/*                                                                      */
/*      Build the WHERE statement appropriate to the current set of     */
/*      criteria (spatial and attribute queries).                       */
/************************************************************************/

void OGRPGTableLayer::BuildWhere()

{
    char        szWHERE[4096];

    CPLFree( pszWHERE );
    pszWHERE = NULL;

    szWHERE[0] = '\0';

    if( m_poFilterGeom != NULL && bHasPostGISGeometry )
    {
        OGREnvelope  sEnvelope;

        m_poFilterGeom->getEnvelope( &sEnvelope );
        sprintf( szWHERE, 
                 "WHERE %s && GeometryFromText('BOX3D(%.12f %.12f, %.12f %.12f)'::box3d,%d) ",
                 pszGeomColumn, 
                 sEnvelope.MinX, sEnvelope.MinY, 
                 sEnvelope.MaxX, sEnvelope.MaxY,
                 nSRSId );
    }

    if( pszQuery != NULL )
    {
        if( strlen(szWHERE) == 0 )
            sprintf( szWHERE, "WHERE %s ", pszQuery  );
        else
            sprintf( szWHERE+strlen(szWHERE), "AND %s ", pszQuery );
    }

    pszWHERE = CPLStrdup(szWHERE);
}

/************************************************************************/
/*                      BuildFullQueryStatement()                       */
/************************************************************************/

void OGRPGTableLayer::BuildFullQueryStatement()

{
    if( pszQueryStatement != NULL )
    {
        CPLFree( pszQueryStatement );
        pszQueryStatement = NULL;
    }