Update DBSpace Statistics -- Fields and controls

" " Update statistics for all columns
" " Update statistics for a column which is the first column of any index
" " OK
" " Cancel
" " Show SQL



" " Update statistics for all columns

Updates the statistics for all columns in every table in the selected dbspace.

" " Update statistics for a column which is the first column of any index

Updates only the statistics for the columns which are the first column in any index in every table in the selected dbspace.

" " Name

Contains the name given to the DBSPACE by the user who acquired it. If the DBSPACE has not been acquired, the field contains an empty string.

" " DBSpace Number

When the database is generated, this is the number that is assigned by the database manager for each DBSPACE (internal use).

" " Owner

The possible values are:

blank
if the DBSPACE is not yet assigned.

owner
if the DBSPACE is PRIVATE.

PUBLIC
if the DBSPACE is PUBLIC.

¬ ¬ ¬ ¬ ¬ ¬ ¬ ¬
if the DBSPACE has been dropped, but has not yet been removed from the database. In this case, DBSPACENAME will contain the number of the DBSPACE to be removed.

" " Type

The possible values are:

1
if the DBSPACE is PUBLIC.

2
if the DBSPACE is PRIVATE.

" " Number of Tables

The number of tables contained in this DBSPACE. This field is updated when CREATE TABLE and DROP TABLE statements are issued.

" " Number of Pages

The number of usable pages in the DBSPACE. NPAGES is specified in the PAGES parameter of the ACQUIRE DBSPACE statement.

Caution:

Changing NPAGES makes the dbspace appear to be a different size without actually changing it. NPAGES should not be changed in a production environment, to do so may cause errors to occur. It is intended for testing purposes only.

" " Number of Header Pages

The number of pages to be used for the DBSPACE header. This number must be between 1 and 8. NRHEADER is specified in the NHEADER parameter of the ACQUIRE DBSPACE statement.

" " Index Page Percentage

The percentage of pages to be used for indexes. PCTINDX is specified in the PCTINDEX parameter of the ACQUIRE DBSPACE statement.

" " Free Space Percentage

The percentage of space on each page to be kept free when rows are inserted. Initially, the database manager gets the value for FREEPCT from the PCTFREE parameter of the ACQUIRE DBSPACE statement. FREEPCT can be updated by the PCTFREE parameter of the ALTER DBSPACE statement.

For package DBSPACEs, FREEPCT is either 0 or 1. A FREEPCT of 0 indicates that the package DBSPACE is full. A FREEPCT of 1 indicates that it is not full.

" " Lock Mode

The possible values are:

S
if the entire DBSPACE is to be locked.

P
if page locking is to be done in this DBSPACE.

T
if row locking is to be done in this DBSPACE.

LOCKMODE is updated by the LOCK parameter of the ACQUIRE DBSPACE and ALTER DBSPACE statements.

" " Number of Active Pages

The number of active data pages in this DBSPACE (set to -1 when the DBSPACE is acquired). This value is the number of data pages that must be read for a complete DBSPACE scan. The value includes all data pages that contain stored rows for this DBSPACE. NACTIVE is set by an UPDATE STATISTICS statement issued for this DBSPACE, or for any table in this DBSPACE, or by creating or reorganizing any index in this DBSPACE, or by the DATALOAD/RELOAD DBS Utility commands if the statistics collection has not been turned off by SET UPDATE STATISTICS OFF. NACTIVE is set to zero for an UPDATE STATISTICS statement issued on a package DBSPACE.

" " Storage Pool

The number of the storage pool into which the database manager places pages that belong to this DBSPACE. POOL is specified using the STORPOOL parameter of the ACQUIRE DBSPACE statement.

If the value of POOL is negative, the storage pool is nonrecoverable. (The absolute value of POOL is the storage pool number).