A database application exists separate from the main application and stores data collections. Every database employs one or multiple APIs for the creation, access, management, search, and replication of the data it contains. Databases also use non-relational data sources such as objects or files. However, databases prove the best option for large datasets, which would suffer from slow retrieval and writing with other data sources. Relational database management systems, or RDBMS, store data in various tables. Relationships between these tables are established using primary keys and foreign keys.
RDBMS offers the following features:
- They enable you to implement a data source with tables, columns, and indices.
- They ensure the integrity of references across rows of multiple tables.
- They automatically update indices.
- They interpret SQL queries and operations in manipulating or sourcing data from tables.
RDBMS Terminology
Before we begin our discussion of MariaDB, let us review a few terms related to databases.
- Database – A database is a data source consisting of tables holding related data.
- Table – A table, meaning a spreadsheet, is a matrix containing data.
- Column – A column, meaning data element, is a structure holding data of one type; for example, shipping dates.
- Row – A row is a structure grouping related data; for example, data for a customer. It is also known as a tuple, entry, or record.
- Redundancy – This term refers to storing data twice in order to accelerate the system.
- Primary Key – This refers to a unique, identifying value. This value cannot appear twice within a table, and there is only one row associated with it.
- Foreign Key – A foreign key serves as a link between two tables.
- Compound Key – A compound key, or composite key, is a key that refers to multiple columns. It refers to multiple columns due to a column lacking a unique quality.
- Index – An index is virtually identical to the index of a book.
- Referential Integrity – This term refers to ensuring all foreign key values point to existing rows.