14.1 Introduction
14.1.1 Overview
Common SQL is designed to provide both embedded and transparent access to relational databases from the LispWorks environment. That is, SQL/relational data can be directly manipulated from within Lisp, and also used as necessary when instantiating or accessing particular Lisp objects.
For details of supported database systems, please see the Release Notes.
The SQL interface allows the following:
- Direct use of standard SQL statements as strings
- Mixed symbolic SQL and Common Lisp expressions
- Implicit SQL invocation when instantiating or accessing CLOS objects
The SQL interface provides these features through two complementary layers:
- A functional SQL interface
- An object-oriented SQL interface
The functional interface provides users with Lisp functions which map onto standard SQL DML and DDL commands. Special iteration constructs which utilize these functions are also provided. The object-oriented interface allows users to manipulate database views as CLOS classes viadef-view-class. The two interfaces may be flexibly combined in accordance with system requirements and user preference. For example, a select query can be used to initialize slots in a CLOS instance; conversely, accessing a CLOS slot may trigger an implicit functional query.