Data Access Language, formerly called CL/1, is Apple's client/server protocol for remote data access and is based on ANSI standard SQL (Structured Query Language). DAL is optimized to provide decision-support applications with uniform access to data, regardless of the different brands of databases, the different host platforms, or the different types of networks.
DAL is intended for Macintosh applications that need ad-hoc access to data from multiple data sources. While performance-oriented applications, like transaction-processing applications, can use DAL, such applications, especially in a single database-vendor environment, could be better served by the many solutions available from third-party Macintosh database and tool vendors like Informix, The Ask Group, Inc./Ingres Products, Oracle, Sybase, and others.
DAL uniquely addresses the needs of customers with databases from multiple database vendors. The DAL client software is included as a part of System 7.0 and can be transparently accessed by applications written to the Data Access Manager API. These applications can access data from DAL servers running on host computers, across all DAL-supported networks. Therefore, with the Data Access Manager and the included DAL client software in System 7, applications can "speak" in an identical fashion to many different types of host databases.
Apple Computer Inc. is currently delivering DAL servers through APDA for the following environments:
* VAX/VMS (for DEC Rdb, Informix, Ingres, Oracle, and Sybase)
* MVS/TSO (for IBM DB2)
* VM/CMS (for IBM SQL/DS)
DEC also provides DAL as a part of the DEC PathWORKS product.
Apple is also working with software and hardware vendors to extend DAL client and server support to other industry platforms.