Output for UPDATE STATISTICS from the SET EXPLAIN Statement

The SET EXPLAIN statement can display the plan that UPDATE STATISTICS uses to generate column distributions. The following output is based on the default DBUPSPACE value of 15 megabytes of sort memory, which in this example requires two passes to sort the 21.9 megabytes of data:

UPDATE STATISTICS:
==================

Table: zelaine.t1
Mode: HIGH
Number of Bins: 267 Bin size 2505
Sort data 21.9 MB Sort memory granted 15.0 MB
Estimated number of table scans 2
PASS #1 b
PASS #2 a
Scan 9 Sort 1 Build 2 Insert 0 Close 0 Total 12
Completed pass 1 in 0 minutes 12 seconds
Scan 5 Sort 2 Build 1 Insert 0 Close 0 Total 8
Completed pass 2 in 0 minutes 8 seconds