Line data    Source code

       1             : /******************************************************************************
       2             :  *
       3             :  * Project:  MSSQL Spatial driver
       4             :  * Purpose:  Implements OGRMSSQLSpatialSelectLayer class, layer access to the
       5             :  *results of a SELECT statement executed via ExecuteSQL(). Author:   Tamas
       6             :  *Szekeres, szekerest at gmail.com
       7             :  *
       8             :  ******************************************************************************
       9             :  * Copyright (c) 2010, Tamas Szekeres
      10             :  *
      11             :  * SPDX-License-Identifier: MIT
      12             :  ****************************************************************************/
      13             : 
      14             : #include "cpl_conv.h"
      15             : #include "ogr_mssqlspatial.h"
      16             : 
      17             : // SQL_CA_SS_UDT_TYPE_NAME not defined in unixODBC headers
      18             : #ifndef SQL_CA_SS_BASE
      19             : #define SQL_CA_SS_BASE 1200
      20             : #endif
      21             : 
      22             : #ifndef SQL_CA_SS_UDT_TYPE_NAME
      23             : #define SQL_CA_SS_UDT_TYPE_NAME (SQL_CA_SS_BASE + 20)
      24             : #endif
      25             : 
      26             : /************************************************************************/
      27             : /*                     OGRMSSQLSpatialSelectLayer()                     */
      28             : /************************************************************************/
      29             : 
      30           0 : OGRMSSQLSpatialSelectLayer::OGRMSSQLSpatialSelectLayer(
      31           0 :     OGRMSSQLSpatialDataSource *poDSIn, CPLODBCStatement *poStmtIn)
      32           0 :     : OGRMSSQLSpatialLayer(poDSIn)
      33             : 
      34             : {
      35           0 :     iNextShapeId = 0;
      36           0 :     nSRSId = 0;
      37           0 :     poFeatureDefn = nullptr;
      38             : 
      39           0 :     poStmt = poStmtIn;
      40           0 :     pszBaseStatement = CPLStrdup(poStmtIn->GetCommand());
      41             : 
      42             :     /* identify the geometry column */
      43           0 :     pszGeomColumn = nullptr;
      44           0 :     int iImageCol = -1;
      45           0 :     for (int iColumn = 0; iColumn < poStmt->GetColCount(); iColumn++)
      46             :     {
      47           0 :         if (EQUAL(poStmt->GetColTypeName(iColumn), "image"))
      48             :         {
      49             :             SQLCHAR szTableName[256];
      50           0 :             SQLSMALLINT nTableNameLength = 0;
      51             : 
      52           0 :             SQLColAttribute(poStmt->GetStatement(), (SQLSMALLINT)(iColumn + 1),
      53             :                             SQL_DESC_TABLE_NAME, szTableName,
      54             :                             sizeof(szTableName), &nTableNameLength, nullptr);
      55             : 
      56           0 :             if (nTableNameLength > 0)
      57             :             {
      58             :                 OGRLayer *poBaseLayer =
      59           0 :                     poDS->GetLayerByName((const char *)szTableName);
      60           0 :                 if (poBaseLayer != nullptr &&
      61           0 :                     EQUAL(poBaseLayer->GetGeometryColumn(),
      62             :                           poStmt->GetColName(iColumn)))
      63             :                 {
      64           0 :                     nGeomColumnType = MSSQLCOLTYPE_BINARY;
      65           0 :                     pszGeomColumn = CPLStrdup(poStmt->GetColName(iColumn));
      66             :                     /* copy spatial reference */
      67           0 :                     if (!poSRS && poBaseLayer->GetSpatialRef())
      68           0 :                         poSRS = poBaseLayer->GetSpatialRef()->Clone();
      69           0 :                     break;
      70             :                 }
      71             :             }
      72           0 :             else if (iImageCol == -1)
      73           0 :                 iImageCol = iColumn;
      74             :         }
      75           0 :         else if (EQUAL(poStmt->GetColTypeName(iColumn), "geometry"))
      76             :         {
      77           0 :             nGeomColumnType = MSSQLCOLTYPE_GEOMETRY;
      78           0 :             pszGeomColumn = CPLStrdup(poStmt->GetColName(iColumn));
      79           0 :             break;
      80             :         }
      81           0 :         else if (EQUAL(poStmt->GetColTypeName(iColumn), "geography"))
      82             :         {
      83           0 :             nGeomColumnType = MSSQLCOLTYPE_GEOGRAPHY;
      84           0 :             pszGeomColumn = CPLStrdup(poStmt->GetColName(iColumn));
      85           0 :             break;
      86             :         }
      87           0 :         else if (EQUAL(poStmt->GetColTypeName(iColumn), "udt"))
      88             :         {
      89             :             SQLCHAR szUDTTypeName[256];
      90           0 :             SQLSMALLINT nUDTTypeNameLength = 0;
      91             : 
      92           0 :             SQLColAttribute(poStmt->GetStatement(), (SQLSMALLINT)(iColumn + 1),
      93             :                             SQL_CA_SS_UDT_TYPE_NAME, szUDTTypeName,
      94             :                             sizeof(szUDTTypeName), &nUDTTypeNameLength,
      95             :                             nullptr);
      96             : 
      97             :             // For some reason on unixODBC, a UCS2 string is returned
      98           0 :             if (EQUAL((char *)szUDTTypeName, "geometry") ||
      99           0 :                 (nUDTTypeNameLength == 16 &&
     100           0 :                  memcmp(szUDTTypeName, "g\0e\0o\0m\0e\0t\0r\0y", 16) == 0))
     101             :             {
     102           0 :                 nGeomColumnType = MSSQLCOLTYPE_GEOMETRY;
     103           0 :                 pszGeomColumn = CPLStrdup(poStmt->GetColName(iColumn));
     104             :             }
     105           0 :             else if (EQUAL((char *)szUDTTypeName, "geography") ||
     106           0 :                      (nUDTTypeNameLength == 18 &&
     107           0 :                       memcmp(szUDTTypeName, "g\0e\0o\0g\0r\0a\0p\0h\0y", 18) ==
     108             :                           0))
     109             :             {
     110           0 :                 nGeomColumnType = MSSQLCOLTYPE_GEOGRAPHY;
     111           0 :                 pszGeomColumn = CPLStrdup(poStmt->GetColName(iColumn));
     112             :             }
     113           0 :             break;
     114             :         }
     115             :     }
     116             : 
     117           0 :     if (pszGeomColumn == nullptr && iImageCol >= 0)
     118             :     {
     119             :         /* set the image col as geometry column as the last resort */
     120           0 :         nGeomColumnType = MSSQLCOLTYPE_BINARY;
     121           0 :         pszGeomColumn = CPLStrdup(poStmt->GetColName(iImageCol));
     122             :     }
     123             : 
     124           0 :     BuildFeatureDefn("SELECT", poStmt);
     125             : 
     126           0 :     if (GetSpatialRef() && poFeatureDefn->GetGeomFieldCount() == 1)
     127           0 :         poFeatureDefn->GetGeomFieldDefn(0)->SetSpatialRef(poSRS);
     128           0 : }
     129             : 
     130             : /************************************************************************/
     131             : /*                    ~OGRMSSQLSpatialSelectLayer()                     */
     132             : /************************************************************************/
     133             : 
     134           0 : OGRMSSQLSpatialSelectLayer::~OGRMSSQLSpatialSelectLayer()
     135             : 
     136             : {
     137           0 :     CPLFree(pszBaseStatement);
     138           0 : }
     139             : 
     140             : /************************************************************************/
     141             : /*                            GetStatement()                            */
     142             : /************************************************************************/
     143             : 
     144           0 : CPLODBCStatement *OGRMSSQLSpatialSelectLayer::GetStatement()
     145             : 
     146             : {
     147           0 :     if (poStmt == nullptr)
     148             :     {
     149           0 :         CPLDebug("OGR_MSSQLSpatial", "Recreating statement.");
     150           0 :         poStmt = new CPLODBCStatement(poDS->GetSession());
     151           0 :         poStmt->Append(pszBaseStatement);
     152             : 
     153           0 :         if (!poStmt->ExecuteSQL())
     154             :         {
     155           0 :             delete poStmt;
     156           0 :             poStmt = nullptr;
     157             :         }
     158             :     }
     159             : 
     160           0 :     return poStmt;
     161             : }
     162             : 
     163             : /************************************************************************/
     164             : /*                             GetFeature()                             */
     165             : /************************************************************************/
     166             : 
     167           0 : OGRFeature *OGRMSSQLSpatialSelectLayer::GetFeature(GIntBig nFeatureId)
     168             : 
     169             : {
     170           0 :     return OGRMSSQLSpatialLayer::GetFeature(nFeatureId);
     171             : }
     172             : 
     173             : /************************************************************************/
     174             : /*                           TestCapability()                           */
     175             : /************************************************************************/
     176             : 
     177           0 : int OGRMSSQLSpatialSelectLayer::TestCapability(const char *pszCap)
     178             : 
     179             : {
     180           0 :     return OGRMSSQLSpatialLayer::TestCapability(pszCap);
     181             : }
     182             : 
     183             : /************************************************************************/
     184             : /*                             GetExtent()                              */
     185             : /*                                                                      */
     186             : /*      Since SELECT layers currently cannot ever have geometry, we     */
     187             : /*      can optimize the GetExtent() method!                            */
     188             : /************************************************************************/
     189             : 
     190           0 : OGRErr OGRMSSQLSpatialSelectLayer::GetExtent(OGREnvelope *, int)
     191             : 
     192             : {
     193           0 :     return OGRERR_FAILURE;
     194             : }
     195             : 
     196             : /************************************************************************/
     197             : /*                          GetFeatureCount()                           */
     198             : /*                                                                      */
     199             : /*      If a spatial filter is in effect, we turn control over to       */
     200             : /*      the generic counter.  Otherwise we return the total count.      */
     201             : /*      Eventually we should consider implementing a more efficient     */
     202             : /*      way of counting features matching a spatial query.              */
     203             : /************************************************************************/
     204             : 
     205           0 : GIntBig OGRMSSQLSpatialSelectLayer::GetFeatureCount(int bForce)
     206             : 
     207             : {
     208           0 :     return OGRMSSQLSpatialLayer::GetFeatureCount(bForce);
     209             : }