SAS/ACCESS 9.2 for Relational Databases: Reference, Fourth Edition

52 SAS/ACCESS Interfaces and Threaded Reads 4 Chapter 6proc reg SIMPLEdata=dblib.salesdata (keep=salesnumber maxsales);var _ALL_;run;Previous versions of SAS opened a single connection and issued:SELECT salesnumber,maxsales FROM SALESDATA;Assuming that SalesData has an integer column EmployeeNum, SAS 9.1, might opentwo connections by issuing these statements:andSELECT salesnumber,maxsales FROM salesdata WHERE (EMPLOYEENUM mod 2)=0;SELECT salesnumber,maxsales FROM SALESDATA WHERE (EMPLOYEENUM mod 2)=1;See “Autopartitioning Techniques in SAS/ACCESS” on page 57 for more informationabout MOD.Note: Might is an important word here. Most but not all SAS/ACCESS interfacessupport threaded reads in SAS 9.1. The partitioning WHERE clauses that SASgenerates vary. In cases where SAS cannot always generate partitioning WHEREclauses, the SAS user can supply them. In addition to WHERE clauses, other ways topartition data might also exist. 4SAS/ACCESS Interfaces and Threaded ReadsHere are the SAS/ACCESS interfaces that support threaded reads. More interfacesare expected to support threaded reads in future releases.3 Aster nCluster3 DB2 Under UNIX and PC Hosts3 DB2 Under z/OS3 Greenplum3 HP Neoview3 Informix3 ODBC3 Oracle (not supported under z/OS)3 Sybase3 Sybase IQ3 Teradata (supports only FastExport threaded reads on z/OS and UNIX; seeTeradata documentation for details)Threaded reads work across all UNIX and Windows platforms where you run SAS.For details about special considerations for Teradata on z/OS, see “AutopartitioningScheme for Teradata” on page 792.Scope of Threaded ReadsSAS steps called threaded applications are automatically eligible for a threaded read.Threaded applications are bottom-to-top fully threaded SAS procedures that perform