ogrmysqltablelayer.cpp

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        {

            osCommand += 
                CPLString().Printf(
                    "GeometryFromText('%s',%d) ", pszWKT, nSRSId );

            OGRFree( pszWKT );
        }
        else
            osCommand += "''";
    }


    // Set the FID 
    if( poFeature->GetFID() != OGRNullFID && pszFIDColumn != NULL )
    {
        if( bNeedComma )
            osCommand += ", ";
        osCommand += CPLString().Printf( "%ld ", poFeature->GetFID() );
        bNeedComma = TRUE;
    }

    for( i = 0; i < poFeatureDefn->GetFieldCount(); i++ )
    {
        const char *pszStrValue = poFeature->GetFieldAsString(i);
        char *pszNeedToFree = NULL;

        if( !poFeature->IsFieldSet( i ) )
            continue;

        if( bNeedComma )
            osCommand += ", ";
        else
            bNeedComma = TRUE;

        if( poFeatureDefn->GetFieldDefn(i)->GetType() != OFTInteger
                 && poFeatureDefn->GetFieldDefn(i)->GetType() != OFTReal )
        {
            int         iChar;

            //We need to quote and escape string fields. 
            osCommand += "'";

            for( iChar = 0; pszStrValue[iChar] != '\0'; iChar++ )
            {
                if( poFeatureDefn->GetFieldDefn(i)->GetType() != OFTIntegerList
                    && poFeatureDefn->GetFieldDefn(i)->GetType() != OFTRealList
                    && poFeatureDefn->GetFieldDefn(i)->GetWidth() > 0
                    && iChar == poFeatureDefn->GetFieldDefn(i)->GetWidth() )
                {
                    CPLDebug( "MYSQL",
                              "Truncated %s field value, it was too long.",
                              poFeatureDefn->GetFieldDefn(i)->GetNameRef() );
                    break;
                }

                if( pszStrValue[iChar] == '\\'
                    || pszStrValue[iChar] == '\'' )
                {
                    osCommand += '\\';
                    osCommand += pszStrValue[iChar];
                }
                else
                    osCommand += pszStrValue[iChar];
            }

            osCommand += "'";
        }
        else
        {
            osCommand += pszStrValue;
        }

        if( pszNeedToFree )
            CPLFree( pszNeedToFree );
    }

    osCommand += ")";
    
    int nQueryResult = mysql_query(poDS->GetConn(), osCommand.c_str() );
    
    if( nQueryResult ){   
        int eErrorCode = mysql_errno(poDS->GetConn());
        if (eErrorCode == 1153) {//ER_NET_PACKET_TOO_LARGE)
            poDS->ReportError("CreateFeature failed because the MySQL server " \
                              "cannot read the entire query statement.  Increase " \
                              "the size of statements your server will allow by " \
                              "altering the 'max_allowed_packet' parameter in "\
                              "your MySQL server configuration.");
        }
        else
        {
        CPLDebug("MYSQL","Error number %d", eErrorCode);
            poDS->ReportError(  osCommand.c_str() );
        }

        // make sure to attempt to free results
        hResult = mysql_store_result( poDS->GetConn() );
        if( hResult != NULL )
            mysql_free_result( hResult );
        hResult = NULL;
            
        return OGRERR_FAILURE;   
    }

    // make sure to attempt to free results of successful queries
    hResult = mysql_store_result( poDS->GetConn() );
    if( hResult != NULL )
        mysql_free_result( hResult );
    hResult = NULL;
    
    return OGRERR_NONE;

}
/************************************************************************/
/*                            CreateField()                             */
/************************************************************************/

OGRErr OGRMySQLTableLayer::CreateField( OGRFieldDefn *poFieldIn, int bApproxOK )

{

    MYSQL_RES           *hResult=NULL;
    char        		szCommand[1024];
    
    char                szFieldType[256];
    OGRFieldDefn        oField( poFieldIn );

/* -------------------------------------------------------------------- */
/*      Do we want to "launder" the column names into Postgres          */
/*      friendly format?                                                */
/* -------------------------------------------------------------------- */
    if( bLaunderColumnNames )
    {
        char    *pszSafeName = poDS->LaunderName( oField.GetNameRef() );

        oField.SetName( pszSafeName );
        CPLFree( pszSafeName );

    }

/* -------------------------------------------------------------------- */
/*      Work out the MySQL type.                                        */
/* -------------------------------------------------------------------- */
    if( oField.GetType() == OFTInteger )
    {
        if( oField.GetWidth() > 0 && bPreservePrecision )
            sprintf( szFieldType, "DECIMAL(%d,0)", oField.GetWidth() );
        else
            strcpy( szFieldType, "INTEGER" );
    }
    else if( oField.GetType() == OFTReal )
    {
        if( oField.GetWidth() > 0 && oField.GetPrecision() > 0
            && bPreservePrecision )
            sprintf( szFieldType, "DOUBLE(%d,%d)",
                     oField.GetWidth(), oField.GetPrecision() );
        else
            strcpy( szFieldType, "DOUBLE" );
    }

    else if( oField.GetType() == OFTDate )
    {
        sprintf( szFieldType, "DATE" );
    }

    else if( oField.GetType() == OFTDateTime )
    {
        sprintf( szFieldType, "DATETIME" );
    }

    else if( oField.GetType() == OFTTime )
    {
        sprintf( szFieldType, "TIME" );
    }

    else if( oField.GetType() == OFTString )
    {
        if( oField.GetWidth() == 0 || !bPreservePrecision )
            strcpy( szFieldType, "TEXT" );
        else
            sprintf( szFieldType, "VARCHAR(%d)", oField.GetWidth() );
    }
    else if( bApproxOK )
    {
        CPLError( CE_Warning, CPLE_NotSupported,
                  "Can't create field %s with type %s on MySQL layers.  Creating as TEXT.",
                  oField.GetNameRef(),
                  OGRFieldDefn::GetFieldTypeName(oField.GetType()) );
        strcpy( szFieldType, "TEXT" );
    }
    else
    {
        CPLError( CE_Failure, CPLE_NotSupported,
                  "Can't create field %s with type %s on MySQL layers.",
                  oField.GetNameRef(),
                  OGRFieldDefn::GetFieldTypeName(oField.GetType()) );

        return OGRERR_FAILURE;
    }

    sprintf( szCommand,
             "ALTER TABLE %s ADD COLUMN %s %s",
             poFeatureDefn->GetName(), oField.GetNameRef(), szFieldType );

    if( mysql_query(poDS->GetConn(), szCommand ) )
    {
        poDS->ReportError( szCommand );
        return OGRERR_FAILURE;
    }

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

    poFeatureDefn->AddFieldDefn( &oField );    
    
    return OGRERR_NONE;
}


/************************************************************************/
/*                             GetFeature()                             */
/************************************************************************/

OGRFeature *OGRMySQLTableLayer::GetFeature( long nFeatureId )

{
    if( pszFIDColumn == NULL )
        return OGRMySQLLayer::GetFeature( nFeatureId );

/* -------------------------------------------------------------------- */
/*      Discard any existing resultset.                                 */
/* -------------------------------------------------------------------- */
    ResetReading();

/* -------------------------------------------------------------------- */
/*      Prepare query command that will just fetch the one record of    */
/*      interest.                                                       */
/* -------------------------------------------------------------------- */
    char        *pszFieldList = BuildFields();
    char        *pszCommand = (char *) CPLMalloc(strlen(pszFieldList)+2000);

    sprintf( pszCommand, 
             "SELECT %s FROM %s WHERE %s = %ld", 
             pszFieldList, poFeatureDefn->GetName(), pszFIDColumn, 
             nFeatureId );
    CPLFree( pszFieldList );

/* -------------------------------------------------------------------- */
/*      Issue the command.                                              */
/* -------------------------------------------------------------------- */
    if( mysql_query( poDS->GetConn(), pszCommand ) )
    {
        poDS->ReportError( pszCommand );
        return NULL;
    }
    CPLFree( pszCommand );

    hResultSet = mysql_store_result( poDS->GetConn() );
    if( hResultSet == NULL )
    {
        poDS->ReportError( "mysql_store_result() failed on query." );
        return NULL;
    }

/* -------------------------------------------------------------------- */
/*      Fetch the result record.                                        */
/* -------------------------------------------------------------------- */
    char **papszRow;
    unsigned long *panLengths;

    papszRow = mysql_fetch_row( hResultSet );
    if( papszRow == NULL )
        return NULL;

    panLengths = mysql_fetch_lengths( hResultSet );

/* -------------------------------------------------------------------- */
/*      Transform into a feature.                                       */
/* -------------------------------------------------------------------- */
    iNextShapeId = nFeatureId;

    OGRFeature *poFeature = RecordToFeature( papszRow, panLengths );

    iNextShapeId = 0;

/* -------------------------------------------------------------------- */
/*      Cleanup                                                         */
/* -------------------------------------------------------------------- */
    if( hResultSet != NULL )
        mysql_free_result( hResultSet );
 		hResultSet = NULL;

    return poFeature;
}

/************************************************************************/
/*                          GetFeatureCount()                           */
/*                                                                      */
/*      If a spatial filter is in effect, we turn control over to       */
/*      the generic counter.  Otherwise we return the total count.      */
/*      Eventually we should consider implementing a more efficient     */
/*      way of counting features matching a spatial query.              */
/************************************************************************/

int OGRMySQLTableLayer::GetFeatureCount( int bForce )

{
/* -------------------------------------------------------------------- */
/*      Ensure any active long result is interrupted.                   */
/* -------------------------------------------------------------------- */
    poDS->InterruptLongResult();
    
/* -------------------------------------------------------------------- */
/*      Issue the appropriate select command.                           */
/* -------------------------------------------------------------------- */
    MYSQL_RES    *hResult;
    const char         *pszCommand;

    pszCommand = CPLSPrintf( "SELECT COUNT(*) FROM %s %s", 
                             poFeatureDefn->GetName(), pszWHERE );

    if( mysql_query( poDS->GetConn(), pszCommand ) )
    {
        poDS->ReportError( pszCommand );
        return FALSE;
    }

    hResult = mysql_store_result( poDS->GetConn() );
    if( hResult == NULL )
    {
        poDS->ReportError( "mysql_store_result() failed on SELECT COUNT(*)." );
        return FALSE;
    }
    
/* -------------------------------------------------------------------- */
/*      Capture the result.                                             */
/* -------------------------------------------------------------------- */
    char **papszRow = mysql_fetch_row( hResult );
    int nCount = 0;

    if( papszRow != NULL && papszRow[0] != NULL )
        nCount = atoi(papszRow[0]);

    if( hResultSet != NULL )
        mysql_free_result( hResultSet );
 		hResultSet = NULL;
    
    return nCount;
}