Kingbasees database administrator's Guide -- 11 manage data files and temporary files

stay KingbaseES in , Creation of data file 、 Naming and deletion are managed internally by the database , These operations are transparent to users . However, you can still manage data files and temporary files according to the following suggestions .

Be careful

Temporary file is a special data file , Data used to store temporary relationships . The tablespace to which the temporary file belongs is determined by the parameter temp_tablespaces control .

• Guidelines for the management of data files

A guide to managing data files for your reference , Contains some suggestions and precautions for managing data files .

11.1.  Guidelines for the management of data files

Suggestions and guidelines for managing data files for your reference .

• About data files

Data files are physical files on a series of file systems , Used to store logical data in the database . stay KingbaseES Data files in do not need to be explicitly created , Instead, it is automatically created and maintained with the operation of objects such as tables and indexes .

• Choose the appropriate file location

The location of the data file depends on the tablespace it belongs to . By specifying the appropriate table space for each table, you can choose the appropriate physical location for the data file , Make rational use of hardware resources .

• Store data files and redo log files separately

Data files and redo log files should not be stored on the same disk drive . If the data file and redo log file are on the same disk drive , When the disk drive fails , We will not be able to recover to the correct data through log redo .

Parent theme ：  Manage data files and temporary files

11.1.1.  About data files

A data file is a physical file that stores logical data in a database .KingbaseES For each database object , As shown in the table 、 Index or view , Generate at least one data file to store the data in it . For ordinary relationships , These files will be in the form of tables or indexes filenode Name No . For temporary relationships , The form of the file name is tBBB_FFF, among BBB Is the background of the background session that created the file ID,FFF Is the file node number . In addition, the data in the relationship exceeds 1GB after , The relationship will be divided into 1G The size of the segment , Each segment is a separate data file , The file name of the first segment is the same as the file node ; The following paragraph is named filenode.1、filenode.2 wait .

Please refer to ：  Storage structure

Parent theme ：  Guidelines for the management of data files

11.1.2.  Choose the appropriate file location

The location of the data file depends on the tablespace it belongs to . For ordinary relationships , The data file will be stored in the table space to which the relationship belongs . For temporary relationships , Temporary files will be stored in temp_tablespaces In the specified table space . By specifying the appropriate table space for each table, you can choose the appropriate physical location for the data file , Make rational use of hardware resources . for example , If there are multiple disk drives available for storing data , Different table spaces are created on each disk drive , Please consider putting the data files that may be accessed in conflict on different disks , So when the user executes the query , Two disk drives can work at the same time , Retrieve data at the same time .

Parent theme ：  Guidelines for the management of data files

11.1.3.  Store data files and redo log files separately

Data files and redo log files should not be stored on the same disk drive . If the data file and redo log file are on the same disk drive , When the disk drive fails , We will not be able to recover to the correct data through log redo , It can only be restored by backing up files . If our redo log file has multiple copies , Then the probability of losing all copies is very low , In this case, we can put the redo log file and data file on the same disk drive .

Parent theme ：  Guidelines for the management of data files