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

SQL/MX Statements
HP NonStop SQL/MX Release 3.2.1 Reference Manual—691117-005
2-308
Considerations for PURGEDATA
Considerations for PURGEDATA
•
An error is returned if you specify a list-of-partitions for a hash-partitioned
table. For hash-partitioned objects, data must be purged from the entire table.
•
Errors are returned if table-name cannot be accessed or if a resource or file
system problem causes the delete to fail.
•
If PURGEDATA fails in response to a process, CPU, or system error, you must run
the RECOVER utility to recover the operation. If the PURGEDATA operation
cannot be canceled, RECOVER returns an error. See Checking DDL Locks on
page 2-9 for details.
•
PURGEDATA records operation progress steps in the DDL_LOCKS metadata
table. Users can query this table to determine the PURGEDATA operation’s
progress:
•
PURGEDATA returns an error if a user transaction exists.
•
PURGEDATA returns an error if you attempt a PURGEDATA operation on an
SQL/MX metadata table (histogram, system defaults, or MXCS metadata tables).
•
PURGEDATA returns an error if a DELETE trigger is defined on table-name,
unless the IGNORE_TRIGGER option is used.
•
PURGEDATA returns an error if table-name is being referenced by one or more
referential integrity constraints, unless all the referencing tables are empty.
PURGEDATA sets the corrupt bit while processing. If PURGEDATA fails before it
completes, the table and its dependent indexes will still be corrupt and you must
run RECOVER with the RESUME option to complete the operation and remove the
data. File system error 59 is returned if you try to access a table whose corrupt bit
is set.
PURGEDATA
Operation
Step Step Progress Status
Step 1 DDL lock has been created.
Step 2 PURGEDATA has passed verification tests.
Step 3 Affected partitions have been marked corrupt.
Step 4 Partition $volume.zsdnnnnn.nnnnnn00 has been purged.*
Step 5 PURGEDATA operation has deleted data from all requested partitions.
Step 6 Affected partitions are now available.
Step 7 DDL lock has been removed.
*
After this step, when any partition has been purged, a rollback using the RECOVER utility is not possible.