Sybase 12.4.2 User Manual

Page 131

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CHAPTER 3 Working with Database Objects

111

The Temporary Store is in c:\company\company.iqtmp

The IQ message log file is in c:\company\company.iqmsg

CREATE DATABASE ’company.db’

IQ SIZE 20

IQ PATH ’c:\\company\\iqdata\\company.iq’

Example

The following statement creates an IQ database called

company.db

. This

database consists of four UNIX files:

The Catalog Store is in company.db, in the directory where the server was
started (in this case, /disk1/company)

The IQ Store is in /disk1/company/iqdata/company.iq

The Temporary Store is in /disk1/company/iqdata/company.iqtmp

The IQ message log file is in /disk1/company/iqdata/company.iqmsg

CREATE DATABASE ’company.db’

IQ SIZE 20

IQ PATH ’/disk1/company/iqdata/company.iq’

Choosing an IQ page size

You set a page size for the IQ Store with the

IQ PAGE SIZE

option. This option

determines memory and disk use. The

IQ PAGE SIZE

must be a power of 2,

from 65536 to 524288 bytes. The IQ page size is the same for all dbspaces in
the IQ Store.

To obtain the best performance, Sybase recommends the following minimum
IQ page sizes:

64 KB (

IQ PAGE SIZE 65536

) for databases whose largest table contains

up to 1 billion rows. Note that this is the default IQ page size, and the
absolute minimum for a new database.

128 KB (

IQ PAGE SIZE 131072

) for databases whose largest table contains

more than 1 billion rows and fewer than 4billion rows.

256 KB (

IQ PAGE SIZE 262144

) for databases whose largest table contains

more than 4 billion rows.

Multiuser environments, and systems with memory constraints, both benefit
from an IQ page size of at least 64KB, as this size minimizes paging.

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