systypes  sysusermessages

Chapter 1: System Tables

sysusages

master database only

Description

sysusages contains one row for each disk allocation piece assigned to a database. Each database contains a specified number of database (logical) page numbers.

The create database command checks sysdevices and sysusages to find available disk allocation pieces. One or more contiguous disk allocation pieces are assigned to the database, and the mapping is recorded in sysusages.

See “System tables that manage space allocation” in Chapter 21, “Creating and Managing User Databases” of the System Administration Guide for more information on sysusages.

NoteWith Adaptive Server version 15.0, the device identification number is stored in the vdevno column and no longer as part of the vstart column. As a consequence, you may need to modify scripts and stored procedures that determine the device identification number based on the earlier schema.

Columns

The columns for sysusages are:

Name

Datatype

Description

dbid

smallint

Database ID

segmap

int

Bitmap of possible segment assignments

lstart

int

First database (logical) page number

size

int

Number of contiguous database (logical) pages

vstart

int

Starting virtual page number

pad

smallint null

Unused

unreservedpgs

int null

Free space not part of an allocated extent

crdate

datetime null

Creation date

vdevno

int

Device identification number

Indexes





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