int OGRSQLiteSelectLayer::TestCapability( const char * pszCap )
{
if (EQUAL(pszCap,OLCFastSpatialFilter))
{
if (osSQLCurrent != osSQLBase)
return TRUE;
size_t i = 0;
OGRSQLiteLayer* poBaseLayer = GetBaseLayer(i);
if (poBaseLayer == NULL)
{
CPLDebug("SQLITE", "Cannot find base layer");
return FALSE;
}
OGRPolygon oFakePoly;
const char* pszWKT = "POLYGON((0 0,0 1,1 1,1 0,0 0))";
oFakePoly.importFromWkt((char**) &pszWKT);
CPLString osSpatialWhere = poBaseLayer->GetSpatialWhere(&oFakePoly);
return osSpatialWhere.size() != 0;
}
else
return OGRSQLiteLayer::TestCapability( pszCap );
}
int OGRSQLiteSelectLayer::RebuildSQLWithSpatialClause()
{
osSQLCurrent = osSQLBase;
if (m_poFilterGeom == NULL)
{
return TRUE;
}
size_t i = 0;
OGRSQLiteLayer* poBaseLayer = GetBaseLayer(i);
if (poBaseLayer == NULL)
{
CPLDebug("SQLITE", "Cannot find base layer");
return FALSE;
}
CPLString osSpatialWhere = poBaseLayer->GetSpatialWhere(m_poFilterGeom);
if (osSpatialWhere.size() == 0)
{
CPLDebug("SQLITE", "Cannot get spatial where clause");
return FALSE;
}
while (i < osSQLBase.size() && osSQLBase[i] == ' ')
i ++;
if (i < osSQLBase.size() && EQUALN(osSQLBase.c_str() + i, "WHERE ", 6))
{
osSQLCurrent = osSQLBase.substr(0, i + 6);
osSQLCurrent += osSpatialWhere;
osSQLCurrent += " AND (";
size_t nEndOfWhere = osSQLBase.ifind(" GROUP ");
if (nEndOfWhere == std::string::npos)
nEndOfWhere = osSQLBase.ifind(" ORDER ");
if (nEndOfWhere == std::string::npos)
nEndOfWhere = osSQLBase.ifind(" LIMIT ");
if (nEndOfWhere == std::string::npos)
{
osSQLCurrent += osSQLBase.substr(i + 6);
osSQLCurrent += ")";
}
else
{
osSQLCurrent += osSQLBase.substr(i + 6, nEndOfWhere - (i + 6));
osSQLCurrent += ")";
osSQLCurrent += osSQLBase.substr(nEndOfWhere);
}
}
else if (i < osSQLBase.size() &&
(EQUALN(osSQLBase.c_str() + i, "GROUP ", 6) ||
EQUALN(osSQLBase.c_str() + i, "ORDER ", 6) ||
EQUALN(osSQLBase.c_str() + i, "LIMIT ", 6)))
{
osSQLCurrent = osSQLBase.substr(0, i);
osSQLCurrent += " WHERE ";
osSQLCurrent += osSpatialWhere;
osSQLCurrent += " ";
osSQLCurrent += osSQLBase.substr(i);
}
else if (i == osSQLBase.size())
{
osSQLCurrent = osSQLBase.substr(0, i);
osSQLCurrent += " WHERE ";
osSQLCurrent += osSpatialWhere;
}
else
{
CPLDebug("SQLITE", "SQL expression too complex for the driver to insert spatial filter in it");
return FALSE;
}
return TRUE;
}
