Extending the Data Warehouse: An Introduction to OLE DB S David Rlba, JADE Tech Inc CleaNlater, FL INTRODUCTION In 1995, I first presented ODBC: Windows to the Outside World, an introduction to the topiC of Open DataBase Connectivity and how to use it effectively. Since then, ODBC has become a useful tool for many SAS sites for cross application access to data. ABSTRACT However, OOBC has its limitations. To address these limitations, and to provide a more flexible Now that you have your data warehoused, how do means of access to many different types of data, you share that infonnation with others who need Microsoft proposed a new standard for data access access to it? SA~ software provides a variety of technology, OLE DB. tools to access and retrieve data from multidimensional databases (MDDBs). However, At SUGI 24, Thomas Cox presented What's Up with MDDBs are not accessible to non-SAS users in your OLE DB?, which provides an excellent overview of organization. Until now. Starting with Version 7 of OLE DB architecture and concepts. This paper will the SAS System, OLE DB can be used to access attempt to provide some additional background on the infonnation stored in SAS MDDBs and eFO OLE DB, and present some techniques for using Vision FOBs. OLE DB to access both SAS and non-SAS data. OLE DB can be used to access the infonnation WHAT IS WRONG WITH ODSC? stored in ANY multidimensional database that is OLE DB compliant. Starting with the release of ODBe was originally proposed by Microsoft in the Windows 2000 Professional, OLE DB will be early 1990's to solve the problem of accessing installed as part of the operating system. In relational and tabular data on the Microsoft Microsoft Office 2000, all member applications will Windows!!) platfonn. It subsequently was ported to be OLE DB consumers. The same is true for Lotus other platfonns and is now a universal method to SmartSulte member applications. Thus, any OLE share data between non-compatible applications on DB compliant consumer (such as Microsoft Excel, a wide variety of hardware platfonns. Lotus 1-2-3, Knosys ProClarity, and many others) will be able to directly query a SAS MDDB file using The ODBe architecture consisted of four tiers: OLE DB on all major platfonns, including Windows NT, UNIX, and mainframes. { ODBC Driver Manager { ODBe Drivers { Applications This paper will provide an introduction to OLE DB. It { Data Sources defined to ODse will describe OLE DB and how it works. The SAS implementation of OLE DB will be demonstrated, The OOBC Driver Manager is typically supplied by along with other OLE DB consumers such as the operating system vendor (e.g. Microsoft). Microsoft Excel and Lotus 1-2-3. The paper is intended as a beginning paper for the advanced OOBC Drivers are typically supplied by the vendor of user. a specific type of data to be accessed with ODBC (e.g. Oracle, SAS, Lotus, etc.). Data Sources are defined by the end user to identify a speCific type of data to be read or written. However, there are several limitations that affect the use of ODBC. These limitations include: 15 { OOSC uses Sal as the common components, which process and transport data language (for example, query processors and cursor { ODBC Olivers are written to different engines). These components are designed to levels integrate smoothly to help OLE OS component { Oeployment issues vendors quickly bling high-quality OLE OS components to market. OLE OS includes a Since OOSC is based on Sal as the common bridge to OOSC to enable continued support for language for communicating between different types the broad range of OOSC relational database of data, the structure of Sal limits the types of data drivers available today. that can be accessed. Sal is best at accessing relational and tabular data. Sal can not be used OLE DB is intended to be an open standard capable effectively to access hierarchical, multi-dimensional of providing access to any type of data. As such, (MOOS), and free-form data. In addition, there are OLE DB will be useful for: many different interpretations of the SQl language, with differing levels of conformance to the Sal { Relational Data specifications. This can cause problems when trying { MultiDimensional Data (MODS) to construct a Sal query for OOSC. { Non-Relational Data { E-Mail OOSC Olivers are individual OlLs written by { Web Data different software vendors to support their specific { Oirectory Services data structures. However, the OOBC standard { IMS and VSAM data specifies several different levels of OOBC compliance, Core, level 1, and level 2. .Each Since OLE DB is an object oriented interface to OOBC dliver is written to one of these compliance data it is intended for use in thin client (web based) levels based on the features that they support. envi;onments. With OLE DB many different types of data can be accessed in a common manner using Oeployment of OOSC has been a problem at many web browsers, database software, stand alone sites. In order for OOSC to function properly, the applications, etc. server operating system, network transport, client softwa~e, and drivers must all be compatible. If this does not happen, troubleshooting OOBC problems IS OOBC OBSOLETE? can be extremely difficult. In many respects, OLE DB can be considered a superset to OoBC. OLE DB incluC!es all of the WHAT IS OLE DB? functionality of OOBC, adds additional functionality, and is easier to use. In fact, OLE OB ships with an In the Summer of 1996, Microsoft published the first OOBC Provider (more on this later). Thus, OLE DB specifications for OLE OB (Object Unking and can perform all of the functionality previously Embedding for DataBases). OLE OB was intended performed by OOBC, with the additional capabilities to overcome the limitations that had become built into OLE DB. apparent in OOSC. However, OLE DB is not intended to replace OOBC. According to Microsoft: The OOBC technology has matured and is widely used. OOBe is still the best choice when accessing OLE OB is an open specification designed to standard relational databases from a non-OLE build on the success of OOSC by providing an environment. OLE DB is still an evolving standard. open standard for accessing all kinds of data It is important to realize that Microsoft is fully throughout the enterprise. OLE OS is a core integrating OLE DB Into its product line (operating technology supporting universal data access. systems and Office suite) as their solution for Whereas oose was created to access relational universal data access. In addition, other vendors databases, OLE OS is designed for the relational such as SAS Institute are adopting OLE DB as a and nonrelational information sources, such as standard for extemal data access. mail stores, text and graphical data for the Web, directory services, and 'IMS and VSAM data In deciding whether to use OoBe or OLE DB, here stored in the mainframe. OLE OB components are some recommendations: consist of data providers, which expose data; data consumers, which use data; and service 16 { Use ODBC to access standaro relational OLE DB for DATA MINING databases from a non-OLE environment { Use OLE DB for non-SQl data In February, 2000, Microsoft updated a draft of a { Use OLE DB in an OLE environment specification for OLE DB for Data Mining. The { OLE DB is the only option for building specification is currently at Version 0.9. In interoperable database components (COM) cooperation with over 40 vendors in the business intelligence field, the OLE DB for OM specification defines a common interface for data mining UNDERSTANDING OLE DB applications. The goal of this specification is to provide an industry standaro for data mining so that Technologically, there is a fundamental difference in different data mining algorithms from various data the architectures of OOBC and OLE DB. mining vendors can be easily plugged into user applications. { ODBC is a procedural based specification OLE DB for OM specifies the API between data { OLE DB is a component based mining consumers and data mining providers. The specification specification does not add any new OLE DB { OOBC is designed to provide access interfaces. Instead, the specification defines a primarily to relational data using SQl in a simple query language similar to SQl syntax and multiplatfonn environment. specialized schema rowsets so consumer { OLE DB is designed to provide access to applications can communicate with data mining all types of data in an OLE Component providers. Object Model (COM) environment. like OLE DB, this area is still evolving and maturing. OLE DB includes the Structured Query language The OLE DB for OM speCification is currently in (SQl) functionality defined in OOBC, but it also public beta. However, the potential benefits from defines interfaces suitable for gaining access to data OLE DB for Data Mining are significant. other than SQl data. OLE DB Is intended to be an open standard capable of providing access to any type of data. In addition, OLE DB for OLAP (OnUne PROVIDERS AND CONSUMERS Analytical Processing) is Intended to extend the features of OLE DB to OLAP data. OLE DB introduces two new terms to the computer lexicon - ·provider" and ·consumer". These tenns Microsoft intended OLE DB to be the foundation of refer to the application software and how they their Universal Data Access strategy. To accomplish interact with OLE DB. this, OLE DB is tightly coupled with ADO (ActiveX Data Objects). ADO is the application level interface { Providers are applications that implement (API) that provides the Component Object Model OLE DB interfaces (COM) objects.