CUBRID supports the following features to completely ensure the atomicity, consistency, isolation and durability in transactions.
A database backup is the process of copying CUBRID database volumes, control files and log files; a database restore is the process of restoring the database to a certain point in time using backup files, active logs and archive logs copied by the backup process. For a restore, there must be the same operating system and the same version of CUBRID installed as in the backup environment.
The backup methods which CUBRID supports include online, offline and incremental backups; the restore methods include restore using incremental backups as well as partial and full restore.
Partitioning is a method by which a table is divided into multiple independent logical units. Each logical unit is called a partition, and each partition is divided into a different physical space. This will lead performance improvement by only allowing access to the partition when retrieving records. CUBRID provides three partitioning methods:
High Availability (HA) refers to ability to minimize system down time while continuing normal operation of server in the event of hareware, software, or network failure; that is, the CUBRID HA is functionality that is applied to CUBRID. The CUBRID HA feature has a shared-nothing architecture. The CUBRID performs realtime monitoring for system and CUBRID state with the CUBRID Heartbeat. Then in case of system failure, it automatically performs failover. It follows the two steps below to synchronize data from the master to the slave database servers.
Replication is a technique that duplicates data from one database to other databases to improve performance and increase server availability by distributing requests from applications that use the same data into multiple databases. Currently, CUBRID supports replication only on Linux and UNIX. The CUBRID replication system runs based on transaction logs, and it provides real-time replication and ensures transaction consistency/schema independence of the slave database. Additionally, it offers a feature for a master database to be minimally affected by replication. The replication feature consists of the following components:
A stored procedure is a method to decrease the complexity of applications and to improve the reusability, security and performance through the separation of database logic and middleware logic. A stored procedure is written in Java (generic language), and provides Java stored procedures running on the Java Virtual Machine (JVM). To execute Java stored procedures in CUBRID, the following steps should be performed:
In the Web, it is a common scenario to count and keep the number of clicks to the database in order to record retrieval history.
The above scenario is generally implemented by using the SELECT and UPDATE statements; SELECT retrieves the data and UPDATE increases the number of clicks for the retrieved queries.
This approach can cause significant performance degradation due to increased lock contention for UPDATE when a number of SELECT statements are executed against the same data.
To address this issue, CUBRID introduces the new concept of the click counter that will support optimized features in the Web in terms of usability and performance, and provides the INCR function and the WITH INCREMENT FOR statement.
For the relational data model, it is not allowed that a single column has multiple values. In CUBRID, however, you can create a column with several values. For this purpose, collection data types are provided in CUBRID. The collection data type is mainly divided into SET, MULTISET and LIST; the types are distinguished by duplicated availability and order.
Inheritance is a concept to reuse columns and methods of a parent table in those of child tables. CUBRID supports reusability through inheritance. By using inheritance provided by CUBRID, you can create a parent table with some common columns and then create child tables inherited from the parent table with some unique columns added. In this way, you can create a database model which can minimize the number of columns.
In a relational database, the reference relationship between tables is defined as a foreign key. If the foreign key consists of multiple columns or the size of the key is significantly large, the performance of join operations between tables will be degraded. However, CUBRID allows the direct use of the physical address (OID) where the records of the referred table are located, so you can define the reference relationship between tables without using join operations.
That is, in an object-oriented database, you can create a composition relation where one record has a reference value to another by using the column displayed in the referred table as a domain (type), instead of referring to the primary key column from the referred table.