We use the phrase “ the SQL standard” to mean the current version of the SQL Standard at any time. In this manual, “ SQL-92” refers to the standard released in 1992, “ SQL:1999” refers to the standard released inġ999, and “ SQL:2003” refers to the current version of the standard. The SQL standard has been evolving since 1986 and several versions exist. SQL is defined by the ANSI/ISO SQL Standard. Programming environment, you might enter SQL directly (for example, to generate reports), embed SQL statements into code written in another language, or use a language-specific API that hides the SQL syntax. SQL is the most common standardized language used to access databases. The SQL part of “ MySQL” stands for “ Structured Query Language”. The database enforces these rules, so that with a well-designed database, your application never sees inconsistent, duplicate, orphan, out-of-date, or missing data. One-to-one, one-to-many, unique, required or optional, and “ pointers” between different tables. You set up rules governing the relationships between different data fields, such as The logical model, with objects such as databases, tables, views, rows, and columns, offers a flexible programming environment.
The database structures are organized into physical files optimized for speed. Since computers are very good at handling large amounts of data, database management systems play a central role in computing, as standalone utilities, or as parts of other applications.Ī relational database stores data in separate tables rather than putting all the data in one big storeroom. To add, access, and process data stored in a computer database, you need a database management system such as MySQL Server. It may be anything from a simple shopping list to a picture gallery or the vast amounts of information in a corporate network.
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