/****************************************************************************** * $Id: ogr_gensql.cpp 10646 2007-01-18 02:38:10Z warmerdam $ * * Project:  OpenGIS Simple Features Reference Implementation * Purpose:  Implements OGRGenSQLResultsLayer. * Author:   Frank Warmerdam, warmerdam@pobox.com * ****************************************************************************** * Copyright (c) 2002, 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. ****************************************************************************/#include "ogr_p.h"#include "ogr_gensql.h"#include "cpl_string.h"CPL_CVSID("$Id: ogr_gensql.cpp 10646 2007-01-18 02:38:10Z warmerdam $");/************************************************************************//*                       OGRGenSQLResultsLayer()                        *//************************************************************************/OGRGenSQLResultsLayer::OGRGenSQLResultsLayer( OGRDataSource *poSrcDS,                                              void *pSelectInfo,                                               OGRGeometry *poSpatFilter ){    swq_select *psSelectInfo = (swq_select *) pSelectInfo;    this->poSrcDS = poSrcDS;    this->pSelectInfo = pSelectInfo;    poDefn = NULL;    poSummaryFeature = NULL;    panFIDIndex = NULL;    nIndexSize = 0;    nNextIndexFID = 0;    nExtraDSCount = 0;    papoExtraDS = NULL;/* -------------------------------------------------------------------- *//*      Identify all the layers involved in the SELECT.                 *//* -------------------------------------------------------------------- */    int iTable;    papoTableLayers = (OGRLayer **)         CPLCalloc( sizeof(OGRLayer *), psSelectInfo->table_count );    for( iTable = 0; iTable < psSelectInfo->table_count; iTable++ )    {        swq_table_def *psTableDef = psSelectInfo->table_defs + iTable;        OGRDataSource *poTableDS = poSrcDS;        if( psTableDef->data_source != NULL )        {            OGRSFDriverRegistrar *poReg=OGRSFDriverRegistrar::GetRegistrar();            poTableDS =                 poReg->OpenShared( psTableDef->data_source, FALSE, NULL );            if( poTableDS == NULL )            {                if( strlen(CPLGetLastErrorMsg()) == 0 )                    CPLError( CE_Failure, CPLE_AppDefined,                               "Unable to open secondary datasource\n"                              "`%s' required by JOIN.",                              psTableDef->data_source );                return;            }            papoExtraDS = (OGRDataSource **)                CPLRealloc( papoExtraDS, sizeof(void*) * ++nExtraDSCount );            papoExtraDS[nExtraDSCount-1] = poTableDS;        }        papoTableLayers[iTable] =             poTableDS->GetLayerByName( psTableDef->table_name );                CPLAssert( papoTableLayers[iTable] != NULL );        if( papoTableLayers[iTable] == NULL )            return;    }        poSrcLayer = papoTableLayers[0];/* -------------------------------------------------------------------- *//*      Now that we have poSrcLayer, we can install a spatial filter    *//*      if there is one.                                                *//* -------------------------------------------------------------------- */    if( poSpatFilter != NULL )        SetSpatialFilter( poSpatFilter );/* -------------------------------------------------------------------- *//*      Prepare a feature definition based on the query.                *//* -------------------------------------------------------------------- */    OGRFeatureDefn *poSrcDefn = poSrcLayer->GetLayerDefn();    poDefn = new OGRFeatureDefn( psSelectInfo->table_defs[0].table_alias );    poDefn->Reference();    iFIDFieldIndex = poSrcDefn->GetFieldCount();    for( int iField = 0; iField < psSelectInfo->result_columns; iField++ )    {        swq_col_def *psColDef = psSelectInfo->column_defs + iField;        OGRFieldDefn oFDefn( psColDef->field_name, OFTInteger );        OGRFieldDefn *poSrcFDefn = NULL;        OGRFeatureDefn *poLayerDefn =             papoTableLayers[psColDef->table_index]->GetLayerDefn();        if( psColDef->field_index > -1             && psColDef->field_index < poLayerDefn->GetFieldCount() )            poSrcFDefn = poLayerDefn->GetFieldDefn(psColDef->field_index);        if( psColDef->col_func_name != NULL )        {            oFDefn.SetName( CPLSPrintf( "%s_%s",psColDef->col_func_name,                                        psColDef->field_name) );        }        if( psColDef->col_func == SWQCF_COUNT )            oFDefn.SetType( OFTInteger );        else if( poSrcFDefn != NULL )        {            oFDefn.SetType( poSrcFDefn->GetType() );            oFDefn.SetWidth( poSrcFDefn->GetWidth() );            oFDefn.SetPrecision( poSrcFDefn->GetPrecision() );        }        else if ( psColDef->field_index >= iFIDFieldIndex )        {            switch ( SpecialFieldTypes[psColDef->field_index-iFIDFieldIndex] )            {              case SWQ_INTEGER:                oFDefn.SetType( OFTInteger );                break;              case SWQ_FLOAT:                oFDefn.SetType( OFTReal );                break;              default:                oFDefn.SetType( OFTString );                break;            }        }        poDefn->AddFieldDefn( &oFDefn );    }    poDefn->SetGeomType( poSrcLayer->GetLayerDefn()->GetGeomType() );/* -------------------------------------------------------------------- *//*      If an ORDER BY is in effect, apply it now.                      *//* -------------------------------------------------------------------- */    if( psSelectInfo->order_specs > 0         && psSelectInfo->query_mode == SWQM_RECORDSET )        CreateOrderByIndex();    ResetReading();}/************************************************************************//*                       ~OGRGenSQLResultsLayer()                       *//************************************************************************/OGRGenSQLResultsLayer::~OGRGenSQLResultsLayer(){    if( m_nFeaturesRead > 0 && poDefn != NULL )    {        CPLDebug( "GenSQL", "%d features read on layer '%s'.",                  (int) m_nFeaturesRead,                   poDefn->GetName() );    }    ClearFilters();/* -------------------------------------------------------------------- *//*      Free various datastructures.                                    *//* -------------------------------------------------------------------- */    CPLFree( papoTableLayers );    papoTableLayers = NULL;                 if( panFIDIndex != NULL )        CPLFree( panFIDIndex );    if( poSummaryFeature )        delete poSummaryFeature;    if( pSelectInfo != NULL )        swq_select_free( (swq_select *) pSelectInfo );    if( poDefn != NULL )    {        poDefn->Release();    }/* -------------------------------------------------------------------- *//*      Release any additional datasources being used in joins.         *//* -------------------------------------------------------------------- */    OGRSFDriverRegistrar *poReg=OGRSFDriverRegistrar::GetRegistrar();    for( int iEDS = 0; iEDS < nExtraDSCount; iEDS++ )        poReg->ReleaseDataSource( papoExtraDS[iEDS] );    CPLFree( papoExtraDS );}/************************************************************************//*                            ClearFilters()                            *//*                                                                      *//*      Clear up all filters currently in place on the target layer,    *//*      and joined layers.  We try not to leave them installed          *//*      except when actively fetching features.                         *//************************************************************************/void OGRGenSQLResultsLayer::ClearFilters(){/* -------------------------------------------------------------------- *//*      Clear any filters installed on the target layer.                *//* -------------------------------------------------------------------- */    if( poSrcLayer != NULL )    {        poSrcLayer->SetAttributeFilter( "" );        poSrcLayer->SetSpatialFilter( NULL );    }/* -------------------------------------------------------------------- *//*      Clear any attribute filter installed on the joined layers.      *//* -------------------------------------------------------------------- */    swq_select *psSelectInfo = (swq_select *) pSelectInfo;    int iJoin;    if( psSelectInfo != NULL )    {        for( iJoin = 0; iJoin < psSelectInfo->join_count; iJoin++ )        {            swq_join_def *psJoinInfo = psSelectInfo->join_defs + iJoin;            OGRLayer *poJoinLayer =                 papoTableLayers[psJoinInfo->secondary_table];                        poJoinLayer->SetAttributeFilter( "" );        }    }}/************************************************************************//*                            ResetReading()                            *//************************************************************************/void OGRGenSQLResultsLayer::ResetReading() {    swq_select *psSelectInfo = (swq_select *) pSelectInfo;    if( psSelectInfo->query_mode == SWQM_RECORDSET )    {        poSrcLayer->SetAttributeFilter( psSelectInfo->whole_where_clause );                poSrcLayer->SetSpatialFilter( m_poFilterGeom );                poSrcLayer->ResetReading();    }    nNextIndexFID = 0;}/************************************************************************//*                           SetNextByIndex()                           *//*                                                                      *//*      If we already have an FID list, we can easily resposition       *//*      ourselves in it.                                                *//************************************************************************/OGRErr OGRGenSQLResultsLayer::SetNextByIndex( long nIndex ){    swq_select *psSelectInfo = (swq_select *) pSelectInfo;    if( psSelectInfo->query_mode == SWQM_SUMMARY_RECORD         || psSelectInfo->query_mode == SWQM_DISTINCT_LIST         || panFIDIndex != NULL )    {        nNextIndexFID = nIndex;        return OGRERR_NONE;    }    else    {        return poSrcLayer->SetNextByIndex( nIndex );    }}/************************************************************************//*                             GetExtent()                              *//************************************************************************/OGRErr OGRGenSQLResultsLayer::GetExtent( OGREnvelope *psExtent,                                          int bForce ){    swq_select *psSelectInfo = (swq_select *) pSelectInfo;    if( psSelectInfo->query_mode == SWQM_RECORDSET )        return poSrcLayer->GetExtent( psExtent, bForce );    else        return OGRERR_FAILURE;}/************************************************************************//*                           GetSpatialRef()                            *//************************************************************************/OGRSpatialReference *OGRGenSQLResultsLayer::GetSpatialRef() {    swq_select *psSelectInfo = (swq_select *) pSelectInfo;    if( psSelectInfo->query_mode != SWQM_RECORDSET )        return NULL;    else        return poSrcLayer->GetSpatialRef();}/************************************************************************//*                          GetFeatureCount()                           *//************************************************************************/int OGRGenSQLResultsLayer::GetFeatureCount( int bForce ){    swq_select *psSelectInfo = (swq_select *) pSelectInfo;    if( psSelectInfo->query_mode != SWQM_RECORDSET )        return 1;    else if( m_poAttrQuery == NULL )        return poSrcLayer->GetFeatureCount( bForce );    else        return OGRLayer::GetFeatureCount( bForce );