SQL/MX 3.2.1 Reference Manual (H06.26+, J06.15+)

Introduction
HP NonStop SQL/MX Release 3.2.1 Reference Manual—691117-004
1-21
Concurrency
Utilities that read
metadata and update
user data:
IMPORT (not using
fast load)
All DML operations
(SELECT, UPDATE,
DELETE, INSERT) can be
performed concurrently.
If there are too many locks
on the partition, DP2
escalates to a table lock
which prevents concurrent
DML operations.
Utilities that read
metadata can
only be performed
concurrently.
Parallel imports
on the same table
are allowed.
Not
recommended.
Utilities that update
metadata and read
and write user data
offline:
MODIFY without
SHARED access*
POPULATE INDEX
Only SELECT is allowed.** Utilities that read
metadata can
only be performed
concurrently.
Not allowed.
Utilities that update
metadata and read
and potentially write
user data online:
MODIFY with
SHARED access
UPDATE STATISTICS
All DML operations are
allowed.
Utilities that read
metadata can
only be performed
concurrently.***
Not allowed.
Utilities that update
data and potentially
change metadata:
FIXUP
FASTCOPY (target
table only)
DUP (target table only)
IMPORT using fast
load
MODIFY when
dropping a hash
partition
PURGEDATA
RESTORE
Not allowed. Concurrent
operations are not
allowed.
Not allowed.
Utilities that read and
update metadata, but
do not change user
data:
UPGRADE
DOWNGRADE
All DML operations. Utilities that only
read metadata.
Not allowed.
Table 1-5. Concurrency Limits on Utility Operations (page2of3)
Utility DML operations Other utilities
DDL
operations