Try modifying your data space requirements as follows:
 
  ■  Use a smaller file buffer in the OPEN statement's
     LEN clause.
  ■  Use the $DYNAMIC metacommand to create dynamic
     arrays. Dynamic array data can usually be much
     larger than static array data.
  ■  Use fixed-length string arrays instead of
     variable-length string arrays.
  ■  Use the smallest data type that accomplishes
     your task. Use integers whenever possible.
  ■  Avoid using many small procedures. QBX creates several
     bytes of control information for each procedure.
  ■  Use CLEAR stack to modify the size of the stack. Use
     only enough stack space to accomplish your task.
  ■  Do not use source lines longer than 256 characters.
     Such lines require allocation of additional
     text buffer space.