Spool Limits
If you find that queries do not run because they run out of spool space, then increase the spool assignment for the user or database having the problem using the MODIFY USER or MODIFY DATABASE statements, respectively. For the syntax and usage notes for these statements, see SQL Data Definition Language.
The maximum size for a spool row is approximately 1MB. This larger row size enhances DML operations that are limited by small spool rows.
The amount of spool space allocated to each user and database is assigned at CREATE USER or CREATE DATABASE time.