lt_tempfile provides a number of support functions to managing temporary files
  generated when work memory is not enough.For more detail, please refer to work_mem
  and lightdb_keep_temp_file.
 
Table F.19. lt_tempfile Functions
Function Description  | 
|---|
         removing temporay file. 's' is used for the current session, '*' is used for all session. For example: select lt_remove_temp_file('*').  | 
         listing temporary file. 's' is used for the current session, '*' is used for all session. For example: select lt_remove_temp_file('*').  | 
  lt_remove_temp_file removes the temporary file in the LTDATA/base/ltsql_tmp/keep directory.
  Returns true on success, false if the specified file is not present
  or the lt_remove_temp_file() call fails; other cases throw errors.
 
  lt_list_temp_file returns the start timestamps, path names and Number of temporary files
  of all the  files in the LTDATA/base/ltsql_tmp directory.