Copyright © 2003, SAS Institute Inc. All rights reserved. SAS is a registered trademark or trademark of SAS Institute Inc. in the USA and other countries. ® indicates USA registration. Other brand and product names are registered trademarks or Trademarks of their respective companies Scaling SAS® Data Access to Oracle® RDBMS Howard Plemmons SAS Institute Inc. Andrew Holdsworth Oracle Corporation

Copyright © 2003, SAS Institute Inc. All rights reserved. Scaling  What is Scaling?

Copyright © 2003, SAS Institute Inc. All rights reserved. Scaling  “To remove the scales of a fish”  “To climb up by means of a scaling ladder”  “To reach the highest point”  Data

Copyright © 2003, SAS Institute Inc. All rights reserved. Scaling Data  Why Scale to Data

Copyright © 2003, SAS Institute Inc. All rights reserved. Scaling Data  SAS tools, SAS/ACCESS®  SAS Procedure and Processes  Oracle tools  Oracle Procedures and Processes

Copyright © 2003, SAS Institute Inc. All rights reserved. Intelligence Value Chain

Copyright © 2003, SAS Institute Inc. All rights reserved. Intelligence Value Chain Silver into Gold

Copyright © 2003, SAS Institute Inc. All rights reserved. SAS System 9

Copyright © 2003, SAS Institute Inc. All rights reserved. SAS V8 vs. SAS System 9 FEATURESAS V8SAS System 9 Libname Engine xx Procedure Interface xx Fast Load xx Threaded Interface x

Copyright © 2003, SAS Institute Inc. All rights reserved. SAS V8 I/O Model

Copyright © 2003, SAS Institute Inc. All rights reserved. Threaded Interface SAS 9

Copyright © 2003, SAS Institute Inc. All rights reserved. SAS Procedures  proc sort  proc summary  proc dmine  proc reg; proc dmreg  proc means  proc loess; proc dmdb  proc glm  proc robustreg

Copyright © 2003, SAS Institute Inc. All rights reserved. SAS/ACCESS® Engines  ORACLE  DB2  Informix  ODBC  Sybase  Teradata

Copyright © 2003, SAS Institute Inc. All rights reserved. Libname and SAS Procedure Controls  dbslice (“where”,”where”,…)  dbsliceparm (ALL,…)  defaults (THREADED_APPS,2)  options sastrace=‘,,t’;  procedure controls – CPU count

Copyright © 2003, SAS Institute Inc. All rights reserved. Options In Action - DBSLICEPARM  -dbsliceparm none  option dbsliceparm=  libname x oracle user=scott pass=tiger dbsliceparm=(threaded_apps,2);  proc print data=y.oratab (dbsliceparm=(all,4)); run;

Copyright © 2003, SAS Institute Inc. All rights reserved. Options In Action - DBSLICE  libname x oracle user=scott pass=tiger;  proc print data=x.oratab (dbslice= (“where x = 100”) );

Copyright © 2003, SAS Institute Inc. All rights reserved. Options In Action – CPUCOUNT, THREADS  CPUCOUNT=  THREADS | NOTHREADS

Copyright © 2003, SAS Institute Inc. All rights reserved. Process  Libname controls  Procedure controls  Execution

Copyright © 2003, SAS Institute Inc. All rights reserved. Linear Scalability Achieved Speedup Scalability – SAS 9 Threaded speedup in PROC REG Run on 12-way Unix Box

Copyright © 2003, SAS Institute Inc. All rights reserved. Scalability – SAS 9 Threaded speedup in PROC SORT Run on 8-way Unix Box Tests run in memory cache

Copyright © 2003, SAS Institute Inc. All rights reserved. What Does This Mean - access  Rows  No Threads - baseline  Two Threads (DBSLICE) – 31%  Six Threads (DBSLICEPARM) – 54% Run on 10-way Unix Box Tests run in memory cache

Copyright © 2003, SAS Institute Inc. All rights reserved. Scaling Data  Data Volumes  Data ACCESS  Data Organization  Scaling using Oracle - Andrew

Copyright © 2003, SAS Institute Inc. All rights reserved. Scaling with  The Star Query  Use of Parallelism  Use of the Direct Path  Use of Specialist Indexes  Use of Analytical Functions  Use of Materialized Views  Use of The Oracle9i Optimizer

Copyright © 2003, SAS Institute Inc. All rights reserved. The Star Query Fact Product Time Geography Customer

Copyright © 2003, SAS Institute Inc. All rights reserved. Star Queries  The star query is a very common DW technique. It is highly optimized in Oracle and can be tuned depending on the type of queries. In summary the more known about the query composition the higher level of optimization possible.

Copyright © 2003, SAS Institute Inc. All rights reserved. Star Query Optimization  The Optimization is 3 step Process 1.Apply query predicates to dimension tables to generate lists of foreign keys into the fact table. 2.Query the fact table using series of single column bit mapped indexes on the foreign keys 3.Having resolved the query within the fact table complete the query by joining back to dimension tables where needed and roll the query up.

Copyright © 2003, SAS Institute Inc. All rights reserved. Star Queries – To enable star queries the DBA should do the following 1.Build single column bitmapped indexes on each foreign key in the fact table 2.Build indexes on the dimension tables for query predicates 3.Build indexes on the dimension tables to assist in the join back and roll up process 4.Generate statistics for the schema 5.Set the parameter STAR_TRANSFORMATION_ENABLED=TRUE

Copyright © 2003, SAS Institute Inc. All rights reserved. Use of Parallelism  Multiple CPUs to execute a single query as well multiple concurrent queries  Execute Table scans, Index probes and scans in parallel  Execute Joins and Sorts in parallel  Execute DML in parallel  Parallelism can be configured manually or automatically

Copyright © 2003, SAS Institute Inc. All rights reserved. Use of Partitioning  Partitioning was originally designed to allow management of large db objects however by partitioning data performance gains can be made by the following Partition pruning Join optimizations  Partitioning can be done by the following methods Range e.g. Data or key ranges List e.g. Discrete values such as State Hash to achieve equal size partitions  Two types of partitioning can be applied

Copyright © 2003, SAS Institute Inc. All rights reserved. Use of The Direct Path  By pass the conventional transaction layer to insert and copy data within the database  SQL*Loader is user currently by SAS  Other options include Insert with /*+ append */ hint Create Table as Select with NOLOGGING  These constructs can be used to transform vast amounts of data rapidly in parallel

Copyright © 2003, SAS Institute Inc. All rights reserved. Specialist Indexes  B-Tree Indexes  Bit Mapped Indexes including join indexes  Functional Indexes

Copyright © 2003, SAS Institute Inc. All rights reserved. Analytical Functions  Oracle has embraced the ANSI OLAP extensions to SQL  These permit faster response times on queries that would require multiple passes of the data with conventional SQL  This allows grouped results and functionality such as moving averages

Copyright © 2003, SAS Institute Inc. All rights reserved. Materialized Views  Materialized view allow automatic use of summary tables without a user having to re- write the query  Well designed materialized views are small in size and can increase performance by orders of magnitude.  Materialized views are in fact Oracle tables and can use all other features to improve performance

Copyright © 2003, SAS Institute Inc. All rights reserved. Oracle9i Optimizer  On upgrade of Oracle Releases the Optimizer behavior will change  The Optimizer is tested with over 400,000 SQL Statements Where plans change between releases the actual query is ran to test for degradation Slower plans are corrected  It is still important to have good representative Statistics  DBMS_STATS package allows parallel generation and migration of schema statistics

Copyright © 2003, SAS Institute Inc. All rights reserved. Oracle9i Optimizer  Some common Optimizer problems seen with Oracle9i Bad or incomplete statistics Init.ora parameters influencing optimizer SQL written for RBO

Copyright © 2003, SAS Institute Inc. All rights reserved. Summary  Oracle and SAS provide techniques for scaling to larger databases by optimizing both query performance and fetch performance.  These techniques are simple to adopt and allow huge productivity improvements  We have identified some core technologies here however this is a partial picture of the SAS/Oracle ability.

Copyright © 2003, SAS Institute Inc. All rights reserved. About the Speakers Howard PlemmonsAndrew Holdsworth Senior Software ManagerDirector SAS Institute Inc.Oracle Corp. SAS Circle500 Oracle Pkwy, Cary, NCRedwood Shores, CA94065 Phone:

Copyright © 2003, SAS Institute Inc. All rights reserved. Other SUGI Papers/Presentations PC File Data Objects Directly from UNIX – 8:00am Tuesday SAS/ACCESS and use of Metadata – Rm 2:30 Lessons in Scalability – SAS Presents – 3:20 Tuesday Data Warehousing section - performance

Copyright © 2003, SAS Institute Inc. All rights reserved. Scaling SAS Data ACCESS to ORACLE RDBMS

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