ogrmysqldatasource.cpp

来自「支持各种栅格图像和矢量图像读取的库」· C++ 代码 · 共 1,104 行 · 第 1/3 页

/*      result sets into RAM.  But only one "streamed" resultset can    */
/*      be active on a database connection at a time.  So we need to    */
/*      maintain a way of closing off an active streaming resultset     */
/*      before any other sort of query with a resultset is              */
/*      executable.  This method (and InterruptLongResult())            */
/*      implement that exclusion.                                       */
/************************************************************************/

void OGRMySQLDataSource::RequestLongResult( OGRMySQLLayer * poNewLayer )

{
    InterruptLongResult();
    poLongResultLayer = poNewLayer;
}

/************************************************************************/
/*                        InterruptLongResult()                         */
/************************************************************************/

void OGRMySQLDataSource::InterruptLongResult()

{
    if( poLongResultLayer != NULL )
    {
        poLongResultLayer->ResetReading();
        poLongResultLayer = NULL;
    }
}


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

int OGRMySQLDataSource::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();
    
    CPLDebug( "MYSQL", "DeleteLayer(%s)", osLayerName.c_str() );

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

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

    sprintf( szCommand,
             "DROP TABLE %s ",
             osLayerName.c_str() );

    if( !mysql_query(GetConn(), szCommand ) )
    {
        CPLDebug("MYSQL","Dropped table %s.", osLayerName.c_str());
        return OGRERR_NONE;
    }
    else
    {
        ReportError( szCommand );
        return OGRERR_FAILURE;
    }

}

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

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

{
    MYSQL_RES           *hResult=NULL;
    char        		szCommand[1024];
    const char          *pszGeometryType;
    const char			*pszGeomColumnName;
    const char 			*pszExpectedFIDName; 
	
    char                *pszLayerName;
    int                 nDimension = 3; // MySQL only supports 2d currently


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

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

    CPLDebug("MYSQL","Creating layer %s.", pszLayerName);

/* -------------------------------------------------------------------- */
/*      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
            {
                CPLFree( pszLayerName );
                CPLError( CE_Failure, CPLE_AppDefined,
                          "Layer %s already exists, CreateLayer failed.\n"
                          "Use the layer creation option OVERWRITE=YES to "
                          "replace it.",
                          pszLayerName );
                return NULL;
            }
        }
    }

    pszGeomColumnName = CSLFetchNameValue( papszOptions, "GEOMETRY_NAME" );
    if (!pszGeomColumnName)
        pszGeomColumnName="SHAPE";

    pszExpectedFIDName = CSLFetchNameValue( papszOptions, "MYSQL_FID" );
    if (!pszExpectedFIDName)
        pszExpectedFIDName="OGR_FID";


    CPLDebug("MYSQL","Geometry Column Name %s.", pszGeomColumnName);
    CPLDebug("MYSQL","FID Column Name %s.", pszExpectedFIDName);

    if( wkbFlatten(eType) == wkbNone )
    {
        sprintf( szCommand,
                 "CREATE TABLE %s ( "
                 "   %s INT UNIQUE NOT NULL AUTO_INCREMENT )",
                 pszLayerName, pszExpectedFIDName );
    }
    else
    {
        sprintf( szCommand,
                 "CREATE TABLE %s ( "
                 "   %s INT UNIQUE NOT NULL AUTO_INCREMENT, "
                 "   %s GEOMETRY NOT NULL )",
                 pszLayerName, pszExpectedFIDName, pszGeomColumnName );
    }

    if( CSLFetchNameValue( papszOptions, "ENGINE" ) != NULL )
    {
        strcat( szCommand, " ENGINE = " );
        strcat( szCommand, CSLFetchNameValue( papszOptions, "ENGINE" ) );
    }
	
    if( !mysql_query(GetConn(), szCommand ) )
    {
        if( mysql_field_count( GetConn() ) == 0 )
            CPLDebug("MYSQL","Created table %s.", pszLayerName);
        else
        {
            ReportError( szCommand );
            return NULL;
        }
    }
    else
    {
        ReportError( szCommand );
        return NULL;
    }

    // make sure to attempt to free results of successful queries
    hResult = mysql_store_result( GetConn() );
    if( hResult != NULL )
        mysql_free_result( hResult );
    hResult = NULL;
    
    // Calling this does no harm
    InitializeMetadataTables();
    
/* -------------------------------------------------------------------- */
/*      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 );

/* -------------------------------------------------------------------- */
/*      Sometimes there is an old crufty 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'",
             pszLayerName );

    if( mysql_query(GetConn(), szCommand ) )
    {
        ReportError( szCommand );
        return NULL;
    }

    // make sure to attempt to free results of successful queries
    hResult = mysql_store_result( GetConn() );
    if( hResult != NULL )
        mysql_free_result( hResult );
    hResult = NULL;   
        
/* -------------------------------------------------------------------- */
/*      Attempt to add this table to the geometry_columns table, if     */
/*      it is a spatial layer.                                          */
/* -------------------------------------------------------------------- */
    if( eType != wkbNone )
    {
        int nCoordDimension;
        if( eType == wkbFlatten(eType) )
            nCoordDimension = 2;
        else
            nCoordDimension = 3;

        switch( wkbFlatten(eType) )
        {
            case wkbPoint:
                pszGeometryType = "POINT";
                break;

            case wkbLineString:
                pszGeometryType = "LINESTRING";
                break;

            case wkbPolygon:
                pszGeometryType = "POLYGON";
                break;

            case wkbMultiPoint:
                pszGeometryType = "MULTIPOINT";
                break;

            case wkbMultiLineString:
                pszGeometryType = "MULTILINESTRING";
                break;

            case wkbMultiPolygon:
                pszGeometryType = "MULTIPOLYGON";
                break;

            case wkbGeometryCollection:
                pszGeometryType = "GEOMETRYCOLLECTION";
                break;

            default:
                pszGeometryType = "GEOMETRY";
                break;

        }

        if( nSRSId == -1 )
            sprintf( szCommand,
                     "INSERT INTO geometry_columns "
                     " (F_TABLE_NAME, "
                     "  F_GEOMETRY_COLUMN, "
                     "  COORD_DIMENSION, "
                     "  TYPE) values "
                     "  ('%s', '%s', %d, '%s')",
                     pszLayerName,
                     pszGeomColumnName,
                     nCoordDimension,
                     pszGeometryType );
        else
            sprintf( szCommand,
                     "INSERT INTO geometry_columns "
                     " (F_TABLE_NAME, "
                     "  F_GEOMETRY_COLUMN, "
                     "  COORD_DIMENSION, "
                     "  SRID, "
                     "  TYPE) values "
                     "  ('%s', '%s', %d, %d, '%s')",
                     pszLayerName,
                     pszGeomColumnName,
                     nCoordDimension,
                     nSRSId,
                     pszGeometryType );

        if( mysql_query(GetConn(), szCommand ) )
        {
            ReportError( szCommand );
            return NULL;
        }

        // make sure to attempt to free results of successful queries
        hResult = mysql_store_result( GetConn() );
        if( hResult != NULL )
            mysql_free_result( hResult );
        hResult = NULL;   
    }

/* -------------------------------------------------------------------- */
/*      Create the spatial index.                                       */
/*                                                                      */
/*      We're doing this before we add geometry and record to the table */
/*      so this may not be exactly the best way to do it.               */
/* -------------------------------------------------------------------- */
    const char *pszSI = CSLFetchNameValue( papszOptions, "SPATIAL_INDEX" );

    if( eType != wkbNone && (pszSI == NULL || CSLTestBoolean(pszSI)) )
    {
        sprintf( szCommand,
                 "ALTER TABLE %s ADD SPATIAL INDEX(%s) ",
                 pszLayerName,
                 pszGeomColumnName);

        if( mysql_query(GetConn(), szCommand ) )
        {
            ReportError( szCommand );
            return NULL;
        }

        // make sure to attempt to free results of successful queries
        hResult = mysql_store_result( GetConn() );
        if( hResult != NULL )
            mysql_free_result( hResult );
        hResult = NULL;   
    }
        
/* -------------------------------------------------------------------- */
/*      Create the layer object.                                        */
/* -------------------------------------------------------------------- */
    OGRMySQLTableLayer     *poLayer;
    OGRErr                  eErr;

    poLayer = new OGRMySQLTableLayer( this, pszLayerName, TRUE, nSRSId );
    eErr = poLayer->Initialize(pszLayerName);
    if (eErr == OGRERR_FAILURE)
        return NULL;

    poLayer->SetLaunderFlag( CSLFetchBoolean(papszOptions,"LAUNDER",TRUE) );
    poLayer->SetPrecisionFlag( CSLFetchBoolean(papszOptions,"PRECISION",TRUE));

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

    papoLayers[nLayers++] = poLayer;

    CPLFree( pszLayerName );

    return poLayer;
}