SQL/MX 3.1 Reference Manual (H06.23+, J06.12+)

Metadata Tables
HP NonStop SQL/MX Release 3.1 Reference Manual—663850-001
10-87
HISTOGRAMS Table
13 READ_COUNT SMALLINT The number of times READ_TIME is updated
since this histogram was last generated.
14 SAMPLE_SECS LARGEINT Number of seconds required to create and
populate sample table in seconds with the
minimum value being 1 sec. If sampling is not
used, this column is set to 0.
15 COL_SECS LARGEINT Number of seconds required to create statistics
from column data for histogram. This column
does not include sample time.
16
SAMPLE_PERCENT
SMALLINT The SAMPLE_PERCENT is calculated using
the following formula:
value_given_by_user X 100
The value can range from 0-10000.
17 CV FLOAT The coefficient of variation. This is a value >=0
that represents the distribution of three
occurrences of each distinct value.
18 REASON CHAR(1) Indicates why this histogram was last created.
M created via manual run of update statistics
I automatic initial creation based on request by
optimizer
N automatic regeneration, recently required by
optimizer
' ' histogram is not generated
19 V1 LARGEINT Reserved for future use
20 V2 LARGEINT Reserved for future use
21 V3 LARGEINT Reserved for future use
22 V4 LARGEINT Reserved for future use
23 V5 VARCHAR(250)
CHARACTER
SET UCS2
Reserved for future use
24 V6 VARCHAR(250)
CHARACTER
SET UCS2
Reserved for future use
* Indicates primary key
Column Name Data Type Description