int OGRSQLiteViewLayer::GetFeatureCount( int bForce )
{
if (HasLayerDefnError())
return 0;
if( !TestCapability(OLCFastFeatureCount) )
return OGRSQLiteLayer::GetFeatureCount( bForce );
/* -------------------------------------------------------------------- */
/* Form count SQL. */
/* -------------------------------------------------------------------- */
const char *pszSQL;
pszSQL = CPLSPrintf( "SELECT count(*) FROM '%s' %s",
pszEscapedTableName, osWHERE.c_str() );
/* -------------------------------------------------------------------- */
/* Execute. */
/* -------------------------------------------------------------------- */
char **papszResult, *pszErrMsg;
int nRowCount, nColCount;
int nResult = -1;
if( sqlite3_get_table( poDS->GetDB(), pszSQL, &papszResult,
&nColCount, &nRowCount, &pszErrMsg ) != SQLITE_OK )
return -1;
if( nRowCount == 1 && nColCount == 1 )
nResult = atoi(papszResult[1]);
sqlite3_free_table( papszResult );
return nResult;
}
OGRFeature *OGRSQLiteViewLayer::GetNextFeature()
{
if (HasLayerDefnError())
return NULL;
return OGRSQLiteLayer::GetNextFeature();
}
OGRSpatialReference *OGRSQLiteViewLayer::GetSpatialRef()
{
if (HasLayerDefnError())
return NULL;
return poSRS;
}
OGRFeature *OGRSQLiteViewLayer::GetFeature( long nFeatureId )
{
if (HasLayerDefnError())
return NULL;
/* -------------------------------------------------------------------- */
/* If we don't have an explicit FID column, just read through */
/* the result set iteratively to find our target. */
/* -------------------------------------------------------------------- */
if( pszFIDColumn == NULL )
return OGRSQLiteLayer::GetFeature( nFeatureId );
/* -------------------------------------------------------------------- */
/* Setup explicit query statement to fetch the record we want. */
/* -------------------------------------------------------------------- */
CPLString osSQL;
int rc;
ClearStatement();
iNextShapeId = nFeatureId;
osSQL.Printf( "SELECT \"%s\", * FROM '%s' WHERE \"%s\" = %d",
OGRSQLiteEscapeName(pszFIDColumn).c_str(),
pszEscapedTableName,
OGRSQLiteEscapeName(pszFIDColumn).c_str(),
(int) nFeatureId );
CPLDebug( "OGR_SQLITE", "exec(%s)", osSQL.c_str() );
rc = sqlite3_prepare( poDS->GetDB(), osSQL, osSQL.size(),
&hStmt, NULL );
if( rc != SQLITE_OK )
{
CPLError( CE_Failure, CPLE_AppDefined,
"In GetFeature(): sqlite3_prepare(%s):\n %s",
osSQL.c_str(), sqlite3_errmsg(poDS->GetDB()) );
return NULL;
}
/* -------------------------------------------------------------------- */
/* Get the feature if possible. */
/* -------------------------------------------------------------------- */
OGRFeature *poFeature = NULL;
poFeature = GetNextRawFeature();
ResetReading();
return poFeature;
}
int OGRSQLiteViewLayer::TestCapability( const char * pszCap )
{
if (HasLayerDefnError())
return FALSE;
if (EQUAL(pszCap,OLCFastFeatureCount))
return m_poFilterGeom == NULL || osGeomColumn.size() == 0 ||
bHasSpatialIndex;
else if (EQUAL(pszCap,OLCFastSpatialFilter))
return bHasSpatialIndex;
else
return OGRSQLiteLayer::TestCapability( pszCap );
}
CPLString OGRSQLiteViewLayer::GetSpatialWhere(OGRGeometry* poFilterGeom)
{
CPLString osSpatialWHERE;
if (HasLayerDefnError())
return "";
if( poFilterGeom != NULL && bHasSpatialIndex )
{
OGREnvelope sEnvelope;
poFilterGeom->getEnvelope( &sEnvelope );
/* We first check that the spatial index table exists */
if (!bHasCheckedSpatialIndexTable)
{
bHasCheckedSpatialIndexTable = TRUE;
char **papszResult;
int nRowCount, nColCount;
char *pszErrMsg = NULL;
CPLString osSQL;
osSQL.Printf("SELECT name FROM sqlite_master "
"WHERE name='idx_%s_%s'",
pszEscapedUnderlyingTableName, osUnderlyingGeometryColumn.c_str());
int rc = sqlite3_get_table( poDS->GetDB(), osSQL.c_str(),
&papszResult, &nRowCount,
&nColCount, &pszErrMsg );
if( rc != SQLITE_OK )
{
CPLError( CE_Failure, CPLE_AppDefined, "Error: %s",
pszErrMsg );
sqlite3_free( pszErrMsg );
bHasSpatialIndex = FALSE;
}
else
{
if (nRowCount != 1)
{
bHasSpatialIndex = FALSE;
}
sqlite3_free_table(papszResult);
}
}
if (bHasSpatialIndex)
{
osSpatialWHERE.Printf("%s IN ( SELECT pkid FROM 'idx_%s_%s' WHERE "
"xmax > %.12f AND xmin < %.12f AND ymax > %.12f AND ymin < %.12f)",
pszFIDColumn,
pszEscapedUnderlyingTableName, osUnderlyingGeometryColumn.c_str(),
sEnvelope.MinX - 1e-11, sEnvelope.MaxX + 1e-11,
sEnvelope.MinY - 1e-11, sEnvelope.MaxY + 1e-11);
}
else
{
CPLDebug("SQLITE", "Count not find idx_%s_%s layer. Disabling spatial index",
pszEscapedUnderlyingTableName, osUnderlyingGeometryColumn.c_str());
}
}
if( poFilterGeom != NULL && bSpatialiteLoaded && !bHasSpatialIndex )
{
OGREnvelope sEnvelope;
poFilterGeom->getEnvelope( &sEnvelope );
/* A bit inefficient but still faster than OGR filtering */
osSpatialWHERE.Printf("MBRIntersects(\"%s\", BuildMBR(%.12f, %.12f, %.12f, %.12f))",
osGeomColumn.c_str(),
sEnvelope.MinX - 1e-11, sEnvelope.MinY - 1e-11,
sEnvelope.MaxX + 1e-11, sEnvelope.MaxY + 1e-11);
}
return osSpatialWHERE;
}
CPLString OGRSQLiteViewLayer::GetSpatialWhere(int iGeomCol,
OGRGeometry* poFilterGeom)
{
if (HasLayerDefnError() || poFeatureDefn == NULL ||
iGeomCol < 0 || iGeomCol >= poFeatureDefn->GetGeomFieldCount())
return "";
if( poFilterGeom != NULL && bHasSpatialIndex )
{
OGREnvelope sEnvelope;
poFilterGeom->getEnvelope( &sEnvelope );
/* We first check that the spatial index table exists */
if (!bHasCheckedSpatialIndexTable)
{
bHasCheckedSpatialIndexTable = TRUE;
char **papszResult;
int nRowCount, nColCount;
char *pszErrMsg = NULL;
CPLString osSQL;
osSQL.Printf("SELECT name FROM sqlite_master "
"WHERE name='idx_%s_%s'",
pszEscapedUnderlyingTableName,
OGRSQLiteEscape(osUnderlyingGeometryColumn).c_str());
int rc = sqlite3_get_table( poDS->GetDB(), osSQL.c_str(),
&papszResult, &nRowCount,
&nColCount, &pszErrMsg );
if( rc != SQLITE_OK )
{
CPLError( CE_Failure, CPLE_AppDefined, "Error: %s",
pszErrMsg );
sqlite3_free( pszErrMsg );
bHasSpatialIndex = FALSE;
}
else
{
if (nRowCount != 1)
{
bHasSpatialIndex = FALSE;
}
sqlite3_free_table(papszResult);
}
}
if (bHasSpatialIndex)
{
return FormatSpatialFilterFromRTree(poFilterGeom,
CPLSPrintf("\"%s\"", OGRSQLiteEscapeName(pszFIDColumn).c_str()),
pszEscapedUnderlyingTableName,
OGRSQLiteEscape(osUnderlyingGeometryColumn).c_str());
}
else
{
CPLDebug("SQLITE", "Count not find idx_%s_%s layer. Disabling spatial index",
pszEscapedUnderlyingTableName, osUnderlyingGeometryColumn.c_str());
}
}
if( poFilterGeom != NULL && poDS->IsSpatialiteLoaded() )
{
return FormatSpatialFilterFromMBR(poFilterGeom,
OGRSQLiteEscapeName(poFeatureDefn->GetGeomFieldDefn(iGeomCol)->GetNameRef()).c_str());
}
return "";
}
