MySQL een RDBMS?

[Kermit the frog]

Is MySQL een echte Relationele Database?

Ja

[Koen]

Je kan wel relaties aanleggen, maar de database zal je niks verbieden als je je niet aan die relaties houdt. Je kan dus geen referentiële integriteit afdwingen, zoals dat in Access bijvoorbeeld wel kan.

[zazzie]

van whatis.com:
rdbms:

A relational database management system (RDBMS) is a program that lets you create, update, and administer a relational database. Most commercial RDBMS's use the Structured Query Language (SQL) to access the database, although SQL was invented after the development of the relational model and is not necessary for its use.

The leading RDBMS products are Oracle, IBM's DB2 and Microsoft's SQL Server. Despite repeated challenges by competing technologies, as well as the claim by some experts that no current RDBMS has fully implemented relational principles, the majority of new corporate databases are still being created and managed with an RDBMS.

relational database

A relational database is a collection of data items organized as a set of formally-described tables from which data can be accessed or reassembled in many different ways without having to reorganize the database tables. The relational database was invented by E. F. Codd at IBM in 1970.

The standard user and application program interface to a relational database is the structured query language (SQL). SQL statements are used both for interactive queries for information from a relational database and for gathering data for reports.

In addition to being relatively easy to create and access, a relational database has the important advantage of being easy to extend. After the original database creation, a new data category can be added without requiring that all existing applications be modified.

A relational database is a set of tables containing data fitted into predefined categories. Each table (which is sometimes called a relation) contains one or more data categories in columns. Each row contains a unique instance of data for the categories defined by the columns. For example, a typical business order entry database would include a table that described a customer with columns for name, address, phone number, and so forth. Another table would describe an order: product, customer, date, sales price, and so forth. A user of the database could obtain a view of the database that fitted the user's needs. For example, a branch office manager might like a view or report on all customers that had bought products after a certain date. A financial services manager in the same company could, from the same tables, obtain a report on accounts that needed to be paid.

When creating a relational database, you can define the domain of possible values in a data column and further constraints that may apply to that data value. For example, a domain of possible customers could allow up to ten possible customer names but be constrained in one table to allowing only three of these customer names to be specifiable.

The definition of a relational database results in a table of metadata or formal descriptions of the tables, columns, domains, and constraints.

heeft dus nix met referentiele integriteit te maken... MySQL is dus een RDBMS

[TouchOfDarkness]

Technisch gezien volgens mij niet, omdat het niet aan een aantal voorwaarden voldoet die een RDBMS eigenlijk moet hebben.

Uit de quote van zazzie:

When creating a relational database, you can define the domain of possible values in a data column and further constraints that may apply to that data value. For example, a domain of possible customers could allow up to ten possible customer names but be constrained in one table to allowing only three of these customer names to be specifiable.

The definition of a relational database results in a table of metadata or formal descriptions of the tables, columns, domains, and constraints.

MySQL ondersteunt geen domains en constraints.

[Chimera]

Kermit the frog schreef op 24-09-2003 @ 14:22:
Is MySQL een echte Relationele Database?

Definieer 'echte'. MySQL implementeert niet alle princiepes achter een RDBMS, maar dat doet praktisch geen enkel RDB.