ogrpgdatasource.cpp

来自「支持各种栅格图像和矢量图像读取的库」· C++ 代码 · 共 1,355 行 · 第 1/4 页

    }

/* -------------------------------------------------------------------- */
/*      Parse the returned table list                                   */
/* -------------------------------------------------------------------- */
    char        **papszTableNames=NULL;
    char        **papszSchemaNames=NULL;
    int           iRecord;

    for( iRecord = 0; iRecord < PQntuples(hResult); iRecord++ )
    {
        const char *pszTable = PQgetvalue(hResult, iRecord, 0);

        if( EQUAL(pszTable,"spatial_ref_sys")
            || EQUAL(pszTable,"geometry_columns") )
            continue;

        papszTableNames = CSLAddString(papszTableNames,
                                       PQgetvalue(hResult, iRecord, 0));
        papszSchemaNames = CSLAddString(papszSchemaNames,
                                       PQgetvalue(hResult, iRecord, 1));

    }

/* -------------------------------------------------------------------- */
/*      Cleanup                                                         */
/* -------------------------------------------------------------------- */
    OGRPGClearResult( hResult );

    hResult = PQexec(hPGConn, "CLOSE mycursor");
    OGRPGClearResult( hResult );

    hResult = PQexec(hPGConn, "COMMIT");
    OGRPGClearResult( hResult );

/* -------------------------------------------------------------------- */
/*      Register the available tables.                                  */
/* -------------------------------------------------------------------- */
    for( iRecord = 0;
         papszTableNames != NULL && papszTableNames[iRecord] != NULL;
         iRecord++ )
    {
        OpenTable( papszTableNames[iRecord], papszSchemaNames[iRecord], bUpdate, FALSE );
    }

    CSLDestroy( papszSchemaNames );
    CSLDestroy( papszTableNames );

/* -------------------------------------------------------------------- */
    return nLayers > 0 || bUpdate;
}

/************************************************************************/
/*                             OpenTable()                              */
/************************************************************************/

int OGRPGDataSource::OpenTable( const char *pszNewName, const char *pszSchemaName, int bUpdate,
                                int bTestOpen )

{
/* -------------------------------------------------------------------- */
/*      Create the layer object.                                        */
/* -------------------------------------------------------------------- */
    OGRPGTableLayer  *poLayer;

    poLayer = new OGRPGTableLayer( this, pszNewName, pszSchemaName, bUpdate );
    if( poLayer->GetLayerDefn() == NULL )
    {
        delete poLayer;
        return FALSE;
    }

/* -------------------------------------------------------------------- */
/*      Add layer to data source layer list.                            */
/* -------------------------------------------------------------------- */
    papoLayers = (OGRPGTableLayer **)
        CPLRealloc( papoLayers,  sizeof(OGRPGTableLayer *) * (nLayers+1) );
    papoLayers[nLayers++] = poLayer;

    return TRUE;
}

/************************************************************************/
/*                            DeleteLayer()                             */
/************************************************************************/

int OGRPGDataSource::DeleteLayer( int iLayer )

{
    if( iLayer < 0 || iLayer >= nLayers )
        return OGRERR_FAILURE;

/* -------------------------------------------------------------------- */
/*      Blow away our OGR structures related to the layer.  This is     */
/*      pretty dangerous if anything has a reference to this layer!     */
/* -------------------------------------------------------------------- */
    CPLString osLayerName = papoLayers[iLayer]->GetLayerDefn()->GetName();
    CPLString osTableName = papoLayers[iLayer]->GetTableName();
    CPLString osSchemaName = papoLayers[iLayer]->GetSchemaName();

    CPLDebug( "OGR_PG", "DeleteLayer(%s)", osLayerName.c_str() );

    delete papoLayers[iLayer];
    memmove( papoLayers + iLayer, papoLayers + iLayer + 1,
             sizeof(void *) * (nLayers - iLayer - 1) );
    nLayers--;

/* -------------------------------------------------------------------- */
/*      Remove from the database.                                       */
/* -------------------------------------------------------------------- */
    PGresult            *hResult;
    char                szCommand[1024];

    hResult = PQexec(hPGConn, "BEGIN");
    OGRPGClearResult( hResult );

    if( bHavePostGIS )
    {
        sprintf( szCommand,
                 "SELECT DropGeometryColumn('%s','%s',(SELECT f_geometry_column from geometry_columns where f_table_name='%s' and f_table_schema='%s' order by f_geometry_column limit 1))",
                 osSchemaName.c_str(), osTableName.c_str(), osTableName.c_str(), osSchemaName.c_str() );

        CPLDebug( "OGR_PG", "PGexec(%s)", szCommand );

        hResult = PQexec( hPGConn, szCommand );
        OGRPGClearResult( hResult );
    }

    sprintf( szCommand, "DROP TABLE %s.\"%s\" CASCADE", osSchemaName.c_str(), osTableName.c_str() );
    CPLDebug( "OGR_PG", "PGexec(%s)", szCommand );
    hResult = PQexec( hPGConn, szCommand );
    OGRPGClearResult( hResult );

    hResult = PQexec(hPGConn, "COMMIT");
    OGRPGClearResult( hResult );

    return OGRERR_NONE;
}

/************************************************************************/
/*                            CreateLayer()                             */
/************************************************************************/

OGRLayer *
OGRPGDataSource::CreateLayer( const char * pszLayerNameIn,
                              OGRSpatialReference *poSRS,
                              OGRwkbGeometryType eType,
                              char ** papszOptions )

{
    PGresult            *hResult;
    char                szCommand[1024];
    const char          *pszGeomType;
    char                *pszLayerName;
    const char          *pszTableName;
    char                *pszSchemaName;
    int                 nDimension = 3;

    if( CSLFetchBoolean(papszOptions,"LAUNDER",TRUE) )
        pszLayerName = LaunderName( pszLayerNameIn );
    else
        pszLayerName = CPLStrdup( pszLayerNameIn );

    if( wkbFlatten(eType) == eType )
        nDimension = 2;

    /* Postgres Schema handling:
       Extract schema name from input layer name or passed with -lco SCHEMA.
       Set layer name to "schema.table" or to "table" if schema == current_schema()
       Usage without schema name is backwards compatible
    */
    pszTableName = strstr(pszLayerNameIn,".");
    if ( pszTableName != NULL )
    {
      int length = pszTableName-pszLayerNameIn;
      pszSchemaName = (char*)CPLMalloc(length);
      strncpy(pszSchemaName, pszLayerNameIn, length);
      pszSchemaName[length] = '\0';
      ++pszTableName; //skip "."
    }
    else
    {
      pszSchemaName = NULL;
      pszTableName = pszLayerNameIn;
    }

/* -------------------------------------------------------------------- */
/*      Set the default schema for the layers.                          */
/* -------------------------------------------------------------------- */
    if( CSLFetchNameValue( papszOptions, "SCHEMA" ) != NULL )
    {
        pszSchemaName = CPLStrdup(CSLFetchNameValue( papszOptions, "SCHEMA" ));
    }

    if ( pszSchemaName == NULL )
    {
      //pszSchemaName = current_schema()
      hResult = PQexec(hPGConn,"SELECT current_schema()");
      if ( hResult && PQntuples(hResult) == 1 && !PQgetisnull(hResult,0,0) )
      {
          pszSchemaName = CPLStrdup(PQgetvalue(hResult,0,0));
      }
      OGRPGClearResult( hResult );
    }

/* -------------------------------------------------------------------- */
/*      Do we already have this layer?  If so, should we blow it        */
/*      away?                                                           */
/* -------------------------------------------------------------------- */
    int iLayer;

    for( iLayer = 0; iLayer < nLayers; iLayer++ )
    {
        if( EQUAL(pszLayerName,papoLayers[iLayer]->GetLayerDefn()->GetName()) )
        {
            if( CSLFetchNameValue( papszOptions, "OVERWRITE" ) != NULL
                && !EQUAL(CSLFetchNameValue(papszOptions,"OVERWRITE"),"NO") )
            {
                DeleteLayer( iLayer );
            }
            else
            {
                CPLError( CE_Failure, CPLE_AppDefined,
                          "Layer %s already exists, CreateLayer failed.\n"
                          "Use the layer creation option OVERWRITE=YES to "
                          "replace it.",
                          pszLayerName );
                CPLFree( pszLayerName );
                CPLFree( pszSchemaName );
                return NULL;
            }
        }
    }

/* -------------------------------------------------------------------- */
/*      Handle the GEOM_TYPE option.                                    */
/* -------------------------------------------------------------------- */
    pszGeomType = CSLFetchNameValue( papszOptions, "GEOM_TYPE" );
    if( pszGeomType == NULL )
    {
        if( bHavePostGIS )
            pszGeomType = "geometry";
        else
            pszGeomType = "bytea";
    }

    if( bHavePostGIS && !EQUAL(pszGeomType,"geometry") )
    {
        CPLError( CE_Failure, CPLE_AppDefined,
                  "Can't override GEOM_TYPE in PostGIS enabled databases.\n"
                  "Creation of layer %s with GEOM_TYPE %s has failed.",
                  pszLayerName, pszGeomType );
        CPLFree( pszLayerName );
        CPLFree( pszSchemaName );
        return NULL;
    }

/* -------------------------------------------------------------------- */
/*      Try to get the SRS Id of this spatial reference system,         */
/*      adding tot the srs table if needed.                             */
/* -------------------------------------------------------------------- */
    int nSRSId = -1;

    if( poSRS != NULL )
        nSRSId = FetchSRSId( poSRS );

/* -------------------------------------------------------------------- */
/*      Create a basic table with the FID.  Also include the            */
/*      geometry if this is not a PostGIS enabled table.                */
/* -------------------------------------------------------------------- */
    hResult = PQexec(hPGConn, "BEGIN");
    OGRPGClearResult( hResult );

    if( !bHavePostGIS )
    {
        sprintf( szCommand,
                 "CREATE TABLE %s.\"%s\" ( "
                 "   OGC_FID SERIAL, "
                 "   WKB_GEOMETRY %s, "
                 "   CONSTRAINT \"%s_pk\" PRIMARY KEY (OGC_FID) )",
                 pszSchemaName, pszTableName, pszGeomType, pszTableName );
    }
    else
    {
        sprintf( szCommand,
                 "CREATE TABLE %s.\"%s\" ( OGC_FID SERIAL, CONSTRAINT \"%s_pk\" PRIMARY KEY (OGC_FID) )",
                 pszSchemaName, pszTableName, pszTableName );
    }

    CPLDebug( "OGR_PG", "PQexec(%s)", szCommand );
    hResult = PQexec(hPGConn, szCommand);
    if( PQresultStatus(hResult) != PGRES_COMMAND_OK )
    {
        CPLError( CE_Failure, CPLE_AppDefined,
                  "%s\n%s", szCommand, PQerrorMessage(hPGConn) );
        CPLFree( pszLayerName );
        CPLFree( pszSchemaName );

        OGRPGClearResult( hResult );
        hResult = PQexec( hPGConn, "ROLLBACK" );
        OGRPGClearResult( hResult );
        return NULL;
    }

    OGRPGClearResult( hResult );

/* -------------------------------------------------------------------- */
/*      Eventually we should be adding this table to a table of         */
/*      "geometric layers", capturing the WKT projection, and           */
/*      perhaps some other housekeeping.                                */
/* -------------------------------------------------------------------- */
    if( bHavePostGIS )
    {
        const char *pszGeometryType;
        const char *pszGFldName;
 
        if( CSLFetchNameValue( papszOptions, "DIM") != NULL )
            nDimension = atoi(CSLFetchNameValue( papszOptions, "DIM"));

        if( CSLFetchNameValue( papszOptions, "GEOMETRY_NAME") != NULL )
            pszGFldName = CSLFetchNameValue( papszOptions, "GEOMETRY_NAME");
	else
	    pszGFldName = "wkb_geometry";

        /* Sometimes there is an old cruft entry in the geometry_columns
         * table if things were not properly cleaned up before.  We make
         * an effort to clean out such cruft.
         */
        sprintf( szCommand,
                 "DELETE FROM geometry_columns WHERE f_table_name = '%s' AND f_table_schema = '%s'",
                 pszTableName, pszSchemaName );

        CPLDebug( "OGR_PG", "PQexec(%s)", szCommand );
        hResult = PQexec(hPGConn, szCommand);
        OGRPGClearResult( hResult );

        switch( wkbFlatten(eType) )
        {
            case wkbPoint: