OGRLayer * OGRSQLiteExecuteSQL( GDALDataset* poDS,
const char *pszStatement,
OGRGeometry *poSpatialFilter,
CPL_UNUSED const char *pszDialect )
{
char* pszTmpDBName = (char*) CPLMalloc(256);
snprintf(pszTmpDBName, 256, "/vsimem/ogr2sqlite/temp_%p.db", pszTmpDBName);
OGRSQLiteDataSource* poSQLiteDS = NULL;
int nRet;
int bSpatialiteDB = FALSE;
CPLString osOldVal;
const char* pszOldVal = CPLGetConfigOption("OGR_SQLITE_STATIC_VIRTUAL_OGR", NULL);
if( pszOldVal != NULL )
{
osOldVal = pszOldVal;
pszOldVal = osOldVal.c_str();
}
/* -------------------------------------------------------------------- */
/* Create in-memory sqlite/spatialite DB */
/* -------------------------------------------------------------------- */
#ifdef HAVE_SPATIALITE
/* -------------------------------------------------------------------- */
/* Creating an empty SpatiaLite DB (with spatial_ref_sys populated */
/* has a significant cost. So at the first attempt, let's make */
/* one and cache it for later use. */
/* -------------------------------------------------------------------- */
#if 1
static size_t nEmptyDBSize = 0;
static GByte* pabyEmptyDB = NULL;
{
static CPLMutex* hMutex = NULL;
CPLMutexHolder oMutexHolder(&hMutex);
static int bTried = FALSE;
if( !bTried &&
CPLTestBool(CPLGetConfigOption("OGR_SQLITE_DIALECT_USE_SPATIALITE", "YES")) )
{
bTried = TRUE;
char* pszCachedFilename = (char*) CPLMalloc(256);
snprintf(pszCachedFilename, 256, "/vsimem/ogr2sqlite/reference_%p.db",
pszCachedFilename);
char** papszOptions = CSLAddString(NULL, "SPATIALITE=YES");
OGRSQLiteDataSource* poCachedDS = new OGRSQLiteDataSource();
nRet = poCachedDS->Create( pszCachedFilename, papszOptions );
CSLDestroy(papszOptions);
papszOptions = NULL;
delete poCachedDS;
if( nRet )
{
/* Note: the reference file keeps the ownership of the data, so that */
/* it gets released with VSICleanupFileManager() */
vsi_l_offset nEmptyDBSizeLarge = 0;
pabyEmptyDB = VSIGetMemFileBuffer( pszCachedFilename, &nEmptyDBSizeLarge, FALSE );
nEmptyDBSize = static_cast<size_t>(nEmptyDBSizeLarge);
}
CPLFree( pszCachedFilename );
}
}
/* The following configuration option is useful mostly for debugging/testing */
if( pabyEmptyDB != NULL && CPLTestBool(CPLGetConfigOption("OGR_SQLITE_DIALECT_USE_SPATIALITE", "YES")) )
{
GByte* pabyEmptyDBClone = (GByte*)VSI_MALLOC_VERBOSE(nEmptyDBSize);
if( pabyEmptyDBClone == NULL )
{
CPLFree(pszTmpDBName);
return NULL;
}
memcpy(pabyEmptyDBClone, pabyEmptyDB, nEmptyDBSize);
VSIFCloseL(VSIFileFromMemBuffer( pszTmpDBName, pabyEmptyDBClone, nEmptyDBSize, TRUE ));
poSQLiteDS = new OGRSQLiteDataSource();
CPLSetThreadLocalConfigOption("OGR_SQLITE_STATIC_VIRTUAL_OGR", "NO");
nRet = poSQLiteDS->Open( pszTmpDBName, TRUE, NULL );
CPLSetThreadLocalConfigOption("OGR_SQLITE_STATIC_VIRTUAL_OGR", pszOldVal);
if( !nRet )
{
/* should not happen really ! */
delete poSQLiteDS;
VSIUnlink(pszTmpDBName);
CPLFree(pszTmpDBName);
return NULL;
}
bSpatialiteDB = TRUE;
}
#else
/* No caching version */
poSQLiteDS = new OGRSQLiteDataSource();
char** papszOptions = CSLAddString(NULL, "SPATIALITE=YES");
CPLSetThreadLocalConfigOption("OGR_SQLITE_STATIC_VIRTUAL_OGR", "NO");
nRet = poSQLiteDS->Create( pszTmpDBName, papszOptions );
CPLSetThreadLocalConfigOption("OGR_SQLITE_STATIC_VIRTUAL_OGR", pszOldVal);
CSLDestroy(papszOptions);
papszOptions = NULL;
if( nRet )
{
bSpatialiteDB = TRUE;
}
#endif
else
{
delete poSQLiteDS;
poSQLiteDS = NULL;
#else // HAVE_SPATIALITE
if( true )
{
#endif // HAVE_SPATIALITE
poSQLiteDS = new OGRSQLiteDataSource();
CPLSetThreadLocalConfigOption("OGR_SQLITE_STATIC_VIRTUAL_OGR", "NO");
nRet = poSQLiteDS->Create( pszTmpDBName, NULL );
CPLSetThreadLocalConfigOption("OGR_SQLITE_STATIC_VIRTUAL_OGR", pszOldVal);
if( !nRet )
{
delete poSQLiteDS;
VSIUnlink(pszTmpDBName);
CPLFree(pszTmpDBName);
return NULL;
}
}
/* -------------------------------------------------------------------- */
/* Attach the Virtual Table OGR2SQLITE module to it. */
/* -------------------------------------------------------------------- */
OGR2SQLITEModule* poModule = OGR2SQLITE_Setup(poDS, poSQLiteDS);
sqlite3* hDB = poSQLiteDS->GetDB();
/* -------------------------------------------------------------------- */
/* Analysze the statement to determine which tables will be used. */
/* -------------------------------------------------------------------- */
std::set<LayerDesc> oSetLayers;
std::set<CPLString> oSetSpatialIndex;
CPLString osModifiedSQL;
OGR2SQLITEGetPotentialLayerNames(pszStatement, oSetLayers,
oSetSpatialIndex, osModifiedSQL);
std::set<LayerDesc>::iterator oIter = oSetLayers.begin();
if( strcmp(pszStatement, osModifiedSQL.c_str()) != 0 )
CPLDebug("OGR", "Modified SQL: %s", osModifiedSQL.c_str());
pszStatement = osModifiedSQL.c_str(); /* do not use it anymore */
int bFoundOGRStyle = ( osModifiedSQL.ifind("OGR_STYLE") != std::string::npos );
/* -------------------------------------------------------------------- */
/* For each of those tables, create a Virtual Table. */
/* -------------------------------------------------------------------- */
OGRLayer* poSingleSrcLayer = NULL;
for(; oIter != oSetLayers.end(); ++oIter)
{
const LayerDesc& oLayerDesc = *oIter;
/*CPLDebug("OGR", "Layer desc : %s, %s, %s, %s",
oLayerDesc.osOriginalStr.c_str(),
oLayerDesc.osSubstitutedName.c_str(),
oLayerDesc.osDSName.c_str(),
oLayerDesc.osLayerName.c_str());*/
CPLString osSQL;
OGRLayer* poLayer = NULL;
CPLString osTableName;
int nExtraDS;
if( oLayerDesc.osDSName.size() == 0 )
{
poLayer = poDS->GetLayerByName(oLayerDesc.osLayerName);
/* Might be a false positive (unlikely) */
if( poLayer == NULL )
continue;
osTableName = oLayerDesc.osLayerName;
nExtraDS = -1;
}
else
{
OGRDataSource* poOtherDS = (OGRDataSource* )
OGROpen(oLayerDesc.osDSName, FALSE, NULL);
if( poOtherDS == NULL )
{
CPLError(CE_Failure, CPLE_AppDefined,
"Cannot open datasource '%s'",
oLayerDesc.osDSName.c_str() );
delete poSQLiteDS;
VSIUnlink(pszTmpDBName);
CPLFree(pszTmpDBName);
return NULL;
}
poLayer = poOtherDS->GetLayerByName(oLayerDesc.osLayerName);
if( poLayer == NULL )
{
CPLError(CE_Failure, CPLE_AppDefined,
"Cannot find layer '%s' in '%s'",
oLayerDesc.osLayerName.c_str(),
oLayerDesc.osDSName.c_str() );
delete poOtherDS;
delete poSQLiteDS;
VSIUnlink(pszTmpDBName);
CPLFree(pszTmpDBName);
return NULL;
}
osTableName = oLayerDesc.osSubstitutedName;
nExtraDS = OGR2SQLITE_AddExtraDS(poModule, poOtherDS);
}
if( oSetLayers.size() == 1 )
poSingleSrcLayer = poLayer;
osSQL.Printf("CREATE VIRTUAL TABLE \"%s\" USING VirtualOGR(%d,'%s',%d,%d)",
OGRSQLiteEscapeName(osTableName).c_str(),
nExtraDS,
OGRSQLiteEscape(oLayerDesc.osLayerName).c_str(),
bFoundOGRStyle,
TRUE/*bExposeOGRNativeData*/);
char* pszErrMsg = NULL;
int rc = sqlite3_exec( hDB, osSQL.c_str(),
NULL, NULL, &pszErrMsg );
if( rc != SQLITE_OK )
{
CPLError(CE_Failure, CPLE_AppDefined,
"Cannot create virtual table for layer '%s' : %s",
osTableName.c_str(), pszErrMsg);
sqlite3_free(pszErrMsg);
continue;
}
for(int i=0; i<poLayer->GetLayerDefn()->GetGeomFieldCount(); i++)
{
OGR2SQLITEDealWithSpatialColumn(poLayer, i, oLayerDesc,
osTableName, poSQLiteDS, hDB,
bSpatialiteDB, oSetLayers,
oSetSpatialIndex);
}
}
/* -------------------------------------------------------------------- */
/* Reload, so that virtual tables are recognized */
/* -------------------------------------------------------------------- */
poSQLiteDS->ReloadLayers();
/* -------------------------------------------------------------------- */
/* Prepare the statement. */
/* -------------------------------------------------------------------- */
/* This will speed-up layer creation */
/* ORDER BY are costly to evaluate and are not necessary to establish */
/* the layer definition. */
int bUseStatementForGetNextFeature = TRUE;
int bEmptyLayer = FALSE;
sqlite3_stmt *hSQLStmt = NULL;
int rc = sqlite3_prepare( hDB,
pszStatement, -1,
&hSQLStmt, NULL );
if( rc != SQLITE_OK )
{
CPLError( CE_Failure, CPLE_AppDefined,
"In ExecuteSQL(): sqlite3_prepare(%s):\n %s",
pszStatement, sqlite3_errmsg(hDB) );
if( hSQLStmt != NULL )
{
sqlite3_finalize( hSQLStmt );
}
delete poSQLiteDS;
VSIUnlink(pszTmpDBName);
CPLFree(pszTmpDBName);
return NULL;
}
/* -------------------------------------------------------------------- */
/* Do we get a resultset? */
/* -------------------------------------------------------------------- */
rc = sqlite3_step( hSQLStmt );
if( rc != SQLITE_ROW )
{
if ( rc != SQLITE_DONE )
{
CPLError( CE_Failure, CPLE_AppDefined,
"In ExecuteSQL(): sqlite3_step(%s):\n %s",
pszStatement, sqlite3_errmsg(hDB) );
sqlite3_finalize( hSQLStmt );
delete poSQLiteDS;
VSIUnlink(pszTmpDBName);
CPLFree(pszTmpDBName);
return NULL;
}
if( !STARTS_WITH_CI(pszStatement, "SELECT ") )
{
sqlite3_finalize( hSQLStmt );
delete poSQLiteDS;
VSIUnlink(pszTmpDBName);
CPLFree(pszTmpDBName);
return NULL;
}
bUseStatementForGetNextFeature = FALSE;
bEmptyLayer = TRUE;
}
/* -------------------------------------------------------------------- */
/* Create layer. */
/* -------------------------------------------------------------------- */
OGRSQLiteSelectLayer *poLayer = NULL;
poLayer = new OGRSQLiteExecuteSQLLayer( pszTmpDBName,
poSQLiteDS, pszStatement, hSQLStmt,
bUseStatementForGetNextFeature, bEmptyLayer );
if( poSpatialFilter != NULL )
poLayer->SetSpatialFilter( 0, poSpatialFilter );
if( poSingleSrcLayer != NULL )
poLayer->SetMetadata( poSingleSrcLayer->GetMetadata( "NATIVE_DATA" ),
"NATIVE_DATA" );
return poLayer;
}
/************************************************************************/
/* OGRSQLiteGetReferencedLayers() */
/************************************************************************/
std::set<LayerDesc> OGRSQLiteGetReferencedLayers(const char* pszStatement)
{
/* -------------------------------------------------------------------- */
/* Analysze the statement to determine which tables will be used. */
/* -------------------------------------------------------------------- */
std::set<LayerDesc> oSetLayers;
std::set<CPLString> oSetSpatialIndex;
CPLString osModifiedSQL;
OGR2SQLITEGetPotentialLayerNames(pszStatement, oSetLayers,
oSetSpatialIndex, osModifiedSQL);
return oSetLayers;
}
bool NgwGdalIo::createLayer (int &new_layer_id, const NgwLayerInfo &layer_info, QString base_url,
int resource_group_id, QString base_url_copy_features, int layer_id_copy_features)
{
GDALDatasetPtr dataset_p;
u_openDataset(dataset_p, base_url, resource_group_id, false);
if (dataset_p.data() == NULL)
{
error = QObject::tr("Unable to open NGW dataset via GDAL");
return false;
}
QByteArray ba_name(layer_info.name.toUtf8());
OGRwkbGeometryType geom_type = Core::g_findGeomTypeGdal(layer_info.geom_type);
OGRSpatialReference *srs = new OGRSpatialReference();
srs->importFromEPSG(3857);
char **papszOptions = NULL;
papszOptions = CSLAddString(papszOptions, "OVERWRITE=NO");
OGRLayer *layer = dataset_p.data()->CreateLayer(ba_name.data(), srs, geom_type, papszOptions);
CSLDestroy(papszOptions);
OSRRelease(srs);
if (layer == NULL)
{
error = QObject::tr("Unable to create NGW layer via GDAL");
error += QString("\nGDAL error: %1").arg(CPLGetLastErrorMsg());
return false;
}
for (int i = 0; i < layer_info.fields.size(); i++)
{
QByteArray ba_field_name = std::get<0>(layer_info.fields[i]).toUtf8();
OGRFieldType field_type = Core::g_findFieldTypeGdal(std::get<2>(layer_info.fields[i]));
OGRFieldDefn field_defn(ba_field_name.data(), field_type);
layer->CreateField(&field_defn);
// TEMP. There may be another way to create field aliases via GDAL in future.
QString s_field_alias = QString("FIELD_%1_ALIAS").arg(i);
layer->SetMetadataItem(s_field_alias.toUtf8().data(),
std::get<1>(layer_info.fields[i]).toUtf8().data());
// TODO: delete layer if the creation of field was not successfull? What if at the time
// between creation and this deletion some other layer have been created outside? How to
// remove layer in GDAL not by layer index & how to properly get index of a layer in
// GDALDataset?
}
layer->SyncToDisk(); // otherwise NGW id of created resource will not be assigned to the new layer
auto metadata = layer->GetMetadata("");
QString s_new_layer_id = {CSLFetchNameValue(metadata, "id")};
new_layer_id = s_new_layer_id.toInt();
if (base_url_copy_features != "" && layer_id_copy_features != -1)
{
// TODO (important): here we need own credentioals for dataset_p2 !
GDALDatasetPtr dataset_p2;
u_openDataset(dataset_p2, base_url_copy_features.toUtf8().data(), layer_id_copy_features, true);
if (dataset_p2.data() == NULL)
{
// TODO: warning
error = QObject::tr("Unable to open NGW dataset to copy features from");
//return false;
}
else
{
OGRLayer *layer2 = dataset_p2.data()->GetLayer(0);
if (layer2 == NULL)
{
// TODO: warning
error = QObject::tr("Unable to open NGW layer to copy features from");
//return false;
}
else
{
layer2->ResetReading();
OGRFeature *feature;
while ((feature = layer2->GetNextFeature()) != NULL)
{
layer->CreateFeature(feature);
OGRFeature::DestroyFeature(feature);
}
layer->SyncToDisk();
}
}
}
return true;
}
