There's probably a lot of interrelated things going on here.
AUTOEXTEND is a datafile property (tablespaces reside in one or more datafiles,
and tables [or their partitions] are assigned to tablespaces). This would have an
impact on not being to add rows (if the tablespace storage had been exhausted),
but not on query, per se.
There's probably dozens of things that can be done to improve query performance,
but the order in which they should be attempted depends on the answers to these
questions:
+ What geometry storage is being used (ST_GEOMETRY, SDO_GEOMETRY, SDELOB,
SDEBINARY)?
+ Is your table versioned?
+ Have you used DBTUNE keywords to distribute the table(s) and LOBs across
tablespaces?
+ How many rows in your business table?
+ If versioned, how many rows in your adds and deletes tables?
+ If versioned, when was the last time you did a compress?
- V