Sybase 12.4.2 Manuale Utente
CHAPTER 3 Working with Database Objects
107
Creating a database
When you create a database, the database server creates the following four
dbspaces:
dbspaces:
The
SYSTEM
dbspace contains the system tables, which hold the schema
definition as you build your database. It also holds a separate checkpoint log,
rollback log, and optionally a write file, transaction log, and transaction log
mirror, for the Catalog Store.
rollback log, and optionally a write file, transaction log, and transaction log
mirror, for the Catalog Store.
Note
In addition to these database files, the database server also uses a
temporary file to hold information needed during a session. This temporary file
is not the same as the Temporary IQ Store, and is not needed once the database
server shuts down. The file has a server-generated name with the extension
.tmp. Its location is determined by the TEMP environment variable, or the
ASTMP environment variable on UNIX.
is not the same as the Temporary IQ Store, and is not needed once the database
server shuts down. The file has a server-generated name with the extension
.tmp. Its location is determined by the TEMP environment variable, or the
ASTMP environment variable on UNIX.
You create a database using either the
CREATE DATABASE
statement or Sybase
Central. Once the database is created, you can connect to it and build the tables
and other objects that you need in the database.
and other objects that you need in the database.
Before you create
your database
your database
In order to create a database, you must:
•
Start the database server
•
Start either Sybase Central or DBISQL
To create a database in DBISQL, you need to connect to an existing database,
or else start the utility database, a phantom database with no database files and
no data. You must start the utility database before creating new databases if no
databases are built yet. For information on the utility database and its security,
see the Adaptive Server IQ Installation and Configuration Guide.
or else start the utility database, a phantom database with no database files and
no data. You must start the utility database before creating new databases if no
databases are built yet. For information on the utility database and its security,
see the Adaptive Server IQ Installation and Configuration Guide.
If you are creating an IQ database for the first time, see the Introduction to
Adaptive Server IQ for assistance.
Adaptive Server IQ for assistance.
dbspace name
Contents
Default operating
system file name
system file name
IQ_SYSTEM_MAIN
Main (permanent) IQ
Store file
Store file
dbname.iq
IQ_SYSTEM_TEMP
Temporary IQ Store file
dbname.iqtmp
IQ_SYSTEM_MSG
Message log file
dbname.iqmsg
SYSTEM
Catalog Store file
dbname.db