5.8.3 Estimating disk space of a database

With the database session failover functionality, create three types of tables (application information table, session information table, and blank record information table). Estimate the size of disk space to be allocated by referring to the of each database on the basis of table and index information. Note that this information might change in version upgrade or modification patch of Component Container.

Organization of this subsection

(1) Table information
(2) Index information

(1) Table information

This subsection describes the elements of column for each table and number of rows.

Application information table

The following table describes the elements of a column.

Table 5‒10: Elements of a column in application information table
No.	Column name	HiRDB type	ORACLE type	Index existence status
1	`APP_INFO_KEY`	CHAR(128) PRIMARY KEY	VARCHAR2(128) PRIMARY KEY	None
2	`APP_INFO_VALUE`	CHAR(512)	VARCHAR2(512)	None

The number of rows is as follows:

13 + Number of definitions of refer-only requests

Session information storage table

The following table describes the elements of a column.

Table 5‒11: Elements of a column in session information storage table
No.	Column name	HiRDB type	ORACLE type	Index existence status
1	`RECORD_NO`	INTEGER PRIMARY KEY	NUMBER(10,0) PRIMARY KEY	None
2	`SESSIONID`	CHAR(112)	VARCHAR2(112)	Yes
3	`CREATION_TIME`	DECIMAL(23,0)	NUMBER(23,0)	None
4	`MAX_INACTIVE_INTERVAL`	INTEGER	NUMBER(10,0)	None
5	`THIS_ACCESSED_TIME`	DECIMAL(23,0)	NUMBER(23,0)	None
6	`ATTRIBUTES_DATA`	BINARY (maximum size of HTTP session attribute information)^#1	BLOB^#2	None
7	`STATUS`	CHAR(16)	VARCHAR2(16)	None
8	`OWNER_SERVER`	CHAR(512)	VARCHAR2(512)	None
9	`NEXT_FREE_RECORD_NO`	INTEGER	NUMBER(10,0)	None

#1: For details on estimating size of HTTP session attribute information, see 5.8.2 Estimating size of HTTP session attribute information.
#2: Maximum size of the values stored in BLOB column is the maximum size of HTTP session attribute information. For details on estimating size of HTTP session attribute information, see 5.8.2 Estimating size of HTTP session attribute information.

The number of rows is as follows:

If you set to continue the start processing of web applications when negotiation processing fails

Number of global session information stored in the database
If you set to discontinue the start processing of web applications when negotiation processing fails

Maximum value of the number of HttpSession objects

Blank record information table

The following table describes the elements of a column.

Table 5‒12: Elements of a column in blank record information table
No.	Column name	HiRDB type	ORACLE type	Index existence status
1	`BLOCK_NO`	INTEGER PRIMARY KEY	NUMBER(10,0) PRIMARY KEY	None
2	`FREE_RECORD_NO`	INTEGER	NUMBER(10,0)	None

The number of rows is fixed to 10.

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(2) Index information

The following table describes the index of session information storage table.

No.	Index name	UNIQUE attribute	Column name
1	`Application-identifier_SESSIONS_IDX`	None	`SESSIONID`

Reference note

If you use HiRDB, performance might be improved if you satisfy the following conditions:

The tables and indexes used in the database session failover functionality are placed in RD area^#.
Global buffer is set for each table and index placed in RD area.

For details on design of RD area and global buffer, see the HiRDB Installation and Design Guide.

#: If you place tables and indexes in RD area, you must edit the SQL file.

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