Ingres 12.0 | Creating Databases

• Files created when a valid user creates an Ingres table, index, or system catalog. These files have an extension starting with "t" followed by a number (for example, aaaabdef.t00), where the first extent is named t00, and succeeding extensions are named t01, t02, and so on.

Data tables contain the user data and may be referred to as data files. For details, see the chapter "Managing Tables and Views."

System catalog tables contain metadata (for example, descriptions of tables, columns, and views) about the database and are owned by the user $ingres. For a complete description of the system catalogs, see the appendix "System Catalogs."

• The configuration file (aaaaaaaa.cnf).

This is the most important file in the database location. If it is lost or becomes corrupt, connecting to the database is impossible. This file holds a variety of information (for example, date of last checkpoint), which can be viewed using the utility infodb.

• Files created during a modify of a table or index.

These files have an extension starting with "m" (for example, a0aadnoq.m00). These are transient files that exist only during a modify.

Checkpoint location

Contains a snapshot of your database (entire or partial), which is created when you take a checkpoint (ckpdb) of the database.

Journal location

Contains a record of the changes made to the database’s tables and/or system catalogs. Changes to tables are journaled only if journaling is switched on for the database and the table.

Dump

Contains a record of the changes to the database table data that occurred during an online checkpoint. Dump files are used during the recovery (rollforwarddb) of a database that was checkpointed online.

For additional information about checkpoint, journal, and dump files, see the chapter “Performing Backup and Recovery.”

Work location

Contains files used for system work, such as sorting and hash joins within a piece of SQL.

Last modified date: 08/29/2024