Design and implementation of spatial data GSQL parser supporting for multi-threading

To make the extended spatial database based on the ingres database support multi-threaded uploads and downloads of spatial data,the paper designed and implemented a multi-threaded GSQL parser.Based on the analysis of PostGIS parser,it packaged the global variable in the parser to support multi-threading.In order to improve the efficiency of GSQL parser,it proposed and implemented a variable-length memory pool management.Through experimental verification,the GSQL parser performance excellently in a multi-threaded spatial data uploads and downloads,and the variable-length memory pool management system substantially increas the efficiency of the GSQL parser in time and space.