This section lists some database-related terms and their meanings.
Column |
The set of all instances of a given field from all records in a table . |
Database |
One or more large structured sets of persistent data, usually associated with software to update and query the data. A simple database might be a single file containing many records , each of which contains the same set of fields where each field is a certain fixed width. |
Data Modelling |
The product of the database design process which aims to identify and organize the required data logically and physically. |
Data Warehousing |
A database, often remote, containing recent snapshots of corporate data. Planners and researchers can use this database freely without worrying about slowing down day-to-day operations of the production database. |
ETL |
Extraction, Transforming and Loading - the process of maintaining and transforming data into and out of a relational database. |
Foreign key |
A column in a database table containing values that are also found in some primary key column (of a different table). By extension, any reference to entities of a different type. Some RDBMSs allow a column to be explicitly labelled as a foreign key and only allow values to be inserted if they already exist in the relevant primary key column. |
Identifying Relationship |
Where the key of the parent table is a subset of the key of the child table. |
JDBC |
Java DataBase Connectivity, an unofficial acronym for the "java.sql" package of functionality used to access relational databases from programs written in the Java programming language. |
Key |
A value used to identify a record in a database, derived by applying some fixed function to the record. The key is often simply one of the fields (a column if the database is considered as a table with records being rows, see " key field "). Alternatively the key may be obtained by applying some function, e.g. a hash function , to one or more of the fields. The set of keys for all records forms an index . Multiple indexes may be built for one database depending on how it is to be searched. |
Primary key |
The candidate key selected as being most important for identifying a body of information (an entity, object or record ). |
Record (row) |
One or more structured sets of persistent data, usually associated with software to update and query the data. A simple database might be a single file containing many records , each of which contains the same set of fields where each field is a certain fixed width. |
SQL |
Originally SEQUEL and still pronounced that way by many practitioners, SQL is the Standard Query Language; a unified language for creating queries that is accepted (with some variations) by all modern relational databases. |
Table |
A collection of records in a relational database . |
Some of these terms are from FolDoc, "The Free On-line Dictionary of Computing", http://www.foldoc.org/, Editor Denis Howe.