In June 1979, Relational Software introduced one of the first commercially available implementations of SQL, Oracle V2 (Version2) for VAX computers. By 1986, ANSI and ISO …

SQL injection is mostly known as an attack vector for websites but can be used to attack any type of SQL database.

Application- or user-specific database objects in relational databases are usually created with data definition language (DDL) commands, which in SQL for example can be CREATE, ALTER and …

Meaning in SQL A table (called the referencing table) can refer to a column (or a group of columns) in another table (the referenced table) by using a foreign key. The referenced …

PL/SQL refers to a class as an "Abstract Data Type" (ADT) or "User Defined Type" (UDT), and defines it as an Oracle SQL data-type as opposed to a PL/SQL user-defined type, allowing its …

SQL/PSM (SQL Persistent Stored Modules) defines procedural extensions for SQL, such as the IF statement. However, the major SQL vendors have historically included their own proprietary …

Example use Oracle's SQL syntax requires the FROM clause but some queries don't require any tables - DUAL can be used in these cases.

SQL syntax The syntax of the SQL programming language is defined and maintained by ISO/IEC SC 32 as part of ISO/IEC 9075. This standard is not freely available. Despite the existence of …

A join clause in the Structured Query Language (SQL) combines columns from one or more tables into a new table. The operation corresponds to a join operation in relational algebra.

Data query language (DQL) is part of the base grouping of SQL sub-languages. These sub-languages are mainly categorized into four categories: a data query language (DQL), a data …