CPLErr OGRSQLiteViewLayer::EstablishFeatureDefn()
{
int rc;
sqlite3 *hDB = poDS->GetDB();
sqlite3_stmt *hColStmt = NULL;
const char *pszSQL;
OGRSQLiteLayer* poUnderlyingLayer = (OGRSQLiteLayer*) poDS->GetLayerByName(osUnderlyingTableName);
if (poUnderlyingLayer == NULL)
{
CPLError(CE_Failure, CPLE_AppDefined,
"Cannot find underlying layer %s for view %s",
osUnderlyingTableName.c_str(), pszViewName);
return CE_Failure;
}
if ( !poUnderlyingLayer->IsTableLayer() )
{
CPLError(CE_Failure, CPLE_AppDefined,
"Underlying layer %s for view %s is not a regular table",
osUnderlyingTableName.c_str(), pszViewName);
return CE_Failure;
}
const char* pszRealUnderlyingGeometryColumn = poUnderlyingLayer->GetGeometryColumn();
if ( pszRealUnderlyingGeometryColumn == NULL ||
!EQUAL(pszRealUnderlyingGeometryColumn, osUnderlyingGeometryColumn.c_str()) )
{
CPLError(CE_Failure, CPLE_AppDefined,
"Underlying layer %s for view %s has not expected geometry column name (%s instead of %s)",
osUnderlyingTableName.c_str(), pszViewName,
pszRealUnderlyingGeometryColumn ? pszRealUnderlyingGeometryColumn : "(null)",
osUnderlyingGeometryColumn.c_str());
return CE_Failure;
}
poSRS = poUnderlyingLayer->GetSpatialRef();
if (poSRS)
poSRS->Reference();
this->bHasSpatialIndex = poUnderlyingLayer->HasSpatialIndex();
/* -------------------------------------------------------------------- */
/* Get the column definitions for this table. */
/* -------------------------------------------------------------------- */
hColStmt = NULL;
pszSQL = CPLSPrintf( "SELECT %s, * FROM '%s' LIMIT 1", pszFIDColumn, pszEscapedTableName );
rc = sqlite3_prepare( hDB, pszSQL, strlen(pszSQL), &hColStmt, NULL );
if( rc != SQLITE_OK )
{
CPLError( CE_Failure, CPLE_AppDefined,
"Unable to query table %s for column definitions : %s.",
pszViewName, sqlite3_errmsg(hDB) );
return CE_Failure;
}
rc = sqlite3_step( hColStmt );
if ( rc != SQLITE_DONE && rc != SQLITE_ROW )
{
CPLError( CE_Failure, CPLE_AppDefined,
"In Initialize(): sqlite3_step(%s):\n %s",
pszSQL, sqlite3_errmsg(hDB) );
sqlite3_finalize( hColStmt );
return CE_Failure;
}
/* -------------------------------------------------------------------- */
/* Collect the rest of the fields. */
/* -------------------------------------------------------------------- */
BuildFeatureDefn( pszViewName, hColStmt );
sqlite3_finalize( hColStmt );
/* -------------------------------------------------------------------- */
/* Set the geometry type if we know it. */
/* -------------------------------------------------------------------- */
poFeatureDefn->SetGeomType( poUnderlyingLayer->GetGeomType() );
return CE_None;
}
OGRSQLiteLayer* OGRSQLiteSelectLayer::GetBaseLayer(size_t& i)
{
char** papszTokens = CSLTokenizeString(osSQLBase.c_str());
int bCanInsertSpatialFilter = TRUE;
int nCountSelect = 0, nCountFrom = 0, nCountWhere = 0;
for(int iToken = 0; papszTokens[iToken] != NULL; iToken++)
{
if (EQUAL(papszTokens[iToken], "SELECT"))
nCountSelect ++;
else if (EQUAL(papszTokens[iToken], "FROM"))
nCountFrom ++;
else if (EQUAL(papszTokens[iToken], "WHERE"))
nCountWhere ++;
else if (EQUAL(papszTokens[iToken], "UNION") ||
EQUAL(papszTokens[iToken], "JOIN") ||
EQUAL(papszTokens[iToken], "INTERSECT") ||
EQUAL(papszTokens[iToken], "EXCEPT"))
{
bCanInsertSpatialFilter = FALSE;
}
}
CSLDestroy(papszTokens);
if (!(bCanInsertSpatialFilter && nCountSelect == 1 && nCountFrom == 1 && nCountWhere <= 1))
{
CPLDebug("SQLITE", "SQL expression too complex to analyse");
return NULL;
}
size_t nFromPos = osSQLBase.ifind(" from ");
if (nFromPos == std::string::npos)
{
return NULL;
}
int bInSingleQuotes = (osSQLBase[nFromPos + 6] == '\'');
CPLString osBaseLayerName;
for( i = nFromPos + 6 + (bInSingleQuotes ? 1 : 0);
i < osSQLBase.size(); i++ )
{
if (osSQLBase[i] == '\'' && i + 1 < osSQLBase.size() &&
osSQLBase[i + 1] == '\'' )
{
osBaseLayerName += osSQLBase[i];
i++;
}
else if (osSQLBase[i] == '\'' && bInSingleQuotes)
{
i++;
break;
}
else if (osSQLBase[i] == ' ' && !bInSingleQuotes)
break;
else
osBaseLayerName += osSQLBase[i];
}
OGRSQLiteLayer* poUnderlyingLayer = NULL;
if( strchr(osBaseLayerName, '(') == NULL &&
osGeomColumn.size() != 0 )
{
CPLString osNewUnderlyingTableName;
osNewUnderlyingTableName.Printf("%s(%s)",
osBaseLayerName.c_str(),
osGeomColumn.c_str());
poUnderlyingLayer =
(OGRSQLiteLayer*) poDS->GetLayerByName(osNewUnderlyingTableName);
}
if( poUnderlyingLayer == NULL )
poUnderlyingLayer = (OGRSQLiteLayer*) poDS->GetLayerByName(osBaseLayerName);
if( poUnderlyingLayer != NULL && poSRS != NULL &&
poUnderlyingLayer->GetSpatialRef() != NULL &&
poSRS != poUnderlyingLayer->GetSpatialRef() &&
!poSRS->IsSame(poUnderlyingLayer->GetSpatialRef()) )
{
CPLDebug("SQLITE", "Result layer and base layer don't have the same SRS.");
return NULL;
}
return poUnderlyingLayer;
}
