Data Warehouse Designs for Big Data Performance Dave Beulke Dave Beulke and Associates Platform: Cross Platform E10-Wednesday 16-October 2013 9:45-10:45 [email protected] Member of the inaugural IBM DB2 Information Champions One of 45 IBM DB2 Gold Consultant Worldwide Past President of International DB2 Users Group - IDUG Weekly Performance Tips: Best speaker at CMG conference & former TDWI instructor www.DaveBeulke.com Former Co-Author of certification tests DB2 DBA Certification test IBM Business Intelligence certification test Former Columnist for IBM Data Management Magazine Consulting Teaching Educational Seminars CPU Demand Reduction Guaranteed! DB2 Version 10 Transition DB2 Performance Review DB2 Performance for Java Developers DW & Database Design Review Data Warehousing Designs for Performance Security Audit & Compliance How to Do a Performance Review DB2 10 Migration Assistance Data Studio and pureQuery DB2 10 Performance IBM White Paper & Redbook Extensive experience in VLDB databases, DW design and performance Working with DB2 on z/OS since V1.2 Working with DB2 on LUW since OS/2 Extended Edition Designed/implemented first data warehouse in 1988 for E.F. Hutton Working with Java for Syspedia since 2001 – Syspedia - Find, understand and integrate your data faster! Data Warehousing - New and old demands Direct Analysis of the customer’s demographic, location, to tailor advertising Marketing and marketing campaigns to predict profit variability of campaign purchases Cross Selling Analysis of customer’s purchases and behavior to predict their future products desired in a product category Customer Analysis of customer history, company interaction, and services Retention performed to predict customer satisfaction and retention Customer Risk Quantitative analytics to calculate the probabilities of various good and bad events and calculate their business profits/costs Health Analysis of the different drug and physical treatments for conditions, Treatments illnesses and diseases against quality, costs, and outcomes Fraud Detection Transaction analytics to calculate transaction fraud risk for non payment, stolen credit card, location dependencies etc… Financial Market type, company category and financial statements analytics Analytics related to stock pricing, trends and profit probabilities and risk © Copyright Dave Beulke & Associates [email protected] Page 3 Many Solution Architectures • Fact and dimension tables • Ralph Kimball: Centralize DW • One DW serving diverse needs and users • Bill Immon: Information Factory • Wheel Hub and Spoke concept – Central to Mart • Hybrid Operational DW BI Solutions • Customized for your business © Copyright Dave Beulke & Associates [email protected] Page 4 Data Warehousing – Rise of DW Machines • Massively Parallel Machines • Grid • No SQL like Hadoop, MongoDB, GreenPlum etc… • Free databases • Open source • Vendors redefining themselves • Follow the money • Power Electricity • Cooling • Copies of the data © Copyright Dave Beulke & Associates [email protected] Page 5 Partitioning parallelism reduces time Determine I/O requirements per year/month/week/day • Formula = CPU ms + 2-20 ms per call 5B per year = rows per week = 400,000,000 rows = 400,000 CPU seconds + 800,000- 8,000,000 I/O secs • Elapsed time 222 to 2,222 hours processing each week • 10 parallel schedules • (2,222 / 4) / 10 = 55.55 hours • Now we have 100’s of CPU Cores available • SQL Queries • Partitioning encourages query parallelism © Copyright Dave Beulke & Associates [email protected] Page 6 SQL Features RANK Example: DENSE RANK Example: • OLAP functions SELECT WORKDEPT, SELECT WORKDEPT, EMPNO, • RANK AVG(SALARY+BONUS) LASTNAME, FIRSTNME, AS AVG_TOTAL_SALARY, EDLEVEL • DENSE_RANK RANK() OVER (ORDER BY DENSE_RANK() AVG(SALARY+BONUS) OVER (PARTITION BY • ROW_NUMBER DESC) WORKDEPT • ORDER BY clause AS RANK_AVG_SAL ORDER BY EDLEVEL DESC) FROM BEULKE.EMPLOYEE AS RANK_EDLEVEL • OVER clause GROUP BY WORKDEPT FROM EMPLOYEE • PARTITION BY clause ORDER BY RANK_AVG_SAL ORDER BY WORKDEPT, LASTNAME • RANGE clause • ROW clause • ROLLUP ROW NUMBER Example: SELECT ROW_NUMBER() • CUBE OVER (ORDER BY WORKDEPT, LASTNAME) • Group By or Grouping Sets AS NUMBER, LASTNAME, • DB2 Cube Views SALARY • Virtual cube backed by real structures FROM EMPLOYEE ORDER BY WORKDEPT, LASTNAME • XML and Metadata usage © Copyright Dave Beulke & Associates [email protected] Page 7 New Indexes Opportunities • Separate clustering and partitioning indexes • Clustering is not defined through partitioning index • Partitioning can be done in table definition DDL • PARTITION ENDING AT clause • Cluster for biggest workload • Data load/inserts/maintenance • SQL activity usually ?10-25%? scanned ORDER_DEPT_NBR_IX • Compliment MQT aggregates • • Clustering for sort elimination • Partition for parallelism/recovery CUST_ORDERS By Date © Copyright Dave Beulke & Associates [email protected] Page 8 Capture the environment characteristics • Number of CPUs per LPAR available • Virtualization of CPUs VM Ware/Cloud • Amount of LPAR memory available for workload • Amount of paging that is happening • Number of disk drives • Amount of I/O to individual drives • Only get 30%-50% of optimum speed © Copyright Dave Beulke & Associates [email protected] Page 9 Materialized Query Tables • Available on z/OS and LUW • Improved data refresh options • Aggregate via multiple tables • Design and aggregate for users MQT or View Fact-Yearly Fact-1Q Fact-Month Fact-Week Fact-Daily MQT MQT MQT MQT MQT © Copyright Dave Beulke & Associates [email protected] Page 10 MQTs - Requirements & Options • Find all totals, sum and SQL functions used in workload • Analyze base tables and their columns - NULLs • Analyze the types of functions used • SUM, AVG, temporary totals, Counts etc…. • Know data change frequency • SQL UPDATE, INSERT, DELETE • What is the schedule of change activity • Do you need a staging table © Copyright Dave Beulke & Associates [email protected] Page 11 MQT Parameters - Optimization • Setting the optimization level • Three different ways to achieve SQL optimization • System level • DFT_QUERYOPT configuration parameter • BIND level • QUERYOPT optimization-level bind option parameter • Statement level – SQL statement • SET CURRENT QUERY OPTIMIZATION = host variable or number © Copyright Dave Beulke & Associates [email protected] Page 13 MQT Parameters - Optimization • Query rewrite considerations • MQT column definitions • Isolation Level • Special Registers • REFRESH AGE • CURRENT MAINTAINED TABLE TYPES FOR OPTIMIZATION • System, User, All, or None • Only dynamic queries or during BIND • Query rewrite at the query block level • Columns, Predicates, IN-List, GROUP BY items, Derived columns • EXPLAIN: Table_Type = M © Copyright Dave Beulke & Associates [email protected] Page 14 MQT Example • Daily sales figures feed MQTs • Create additive MQTs • MQTs created for all analysis comparison points View Daily Weekly Monthly Quarterly Y-T-D Totals Totals Totals Totals Sales • MQTs can be built from other MQTs • Define Quarterly Sales from Monthly Sales • Combine MQTs through Views • Views over region, territory, store id etc… OLTP Trans Detail from today © Copyright Dave Beulke & Associates [email protected] Page 17 MQT – 10 to 1000 times improvement! • 5B rows per year–10 per 4k page= ½B pages • MQT aggregates save large amounts of everything • Create aggregates for every possibility • “On Demand” information Y-T-D View • Sales by department Fact-Yearly Fact-1Q Fact-Month Fact-Week Fact-Daily • Sales by zip code MQT MQT MQT MQT MQT • Sales by time period – day/week/month/quarter/AP • All reporting and analysis areas • Trace usage to create/eliminate aggregates • Total by month ½B I/Os versus 12 I/Os © Copyright Dave Beulke & Associates [email protected] Page 18 Temporal Data Designs • Example: Create a table, policy_info, that uses a BUSINESS_TIME period CREATE TABLE beulke.policy_info( policy_id CHAR(4) NOT NULL, coverage INT NOT NULL, bus_start DATE NOT NULL, bus_end DATE NOT NULL, PERIOD BUSINESS_TIME(bus_start, bus_end)); • The grain for this temporal table is a DATE • Through the bus_start and bus_end definitions © Copyright Dave Beulke & Associates [email protected] Page 19 Bi-Temporal Data Designs • Inserts data along with both time constraints • UPDATE or DELETE can result in many more data rows • Must consider two dimensions! CREATE TABLE beulke.policy_info( BUSINESS_TIME policy_id CHAR(4) NOT NULL, coverage INT NOT NULL, bus_start DATE NOT NULL, bus_end DATE NOT NULL, sys__starttime TIMESTAMP(12) NOT NULL GENERATED ALWAYS AS ROW START, sys_endtime TIMESTAMP(12) NOT NULL SYSTEM_TIME GENERATED ALWAYS AS ROW END, PERIOD BUSINESS_TIME(bus_start, bus_end) PERIOD SYSTEM_TIME sys_starttime, sys_endtime); © Copyright Dave Beulke & Associates [email protected] Page 20 Temporal tables business_time • Can contain status of the business on a certain day! • Separate business time from system time • Just because you can have bi-temporal does not mean it fits your application • Sometimes fits for DW applications and transactional systems • Complexity with the SQL & processes to make sure the business situation is valid • Can also use SQL for future business_time © Copyright Dave Beulke & Associates [email protected] Page 21 Temporal Tables system_time • SYSTEM_TIME relative to the world • Constant relative across all the processing • Reflects the latest status of the processing • Transactions can be unique within the overall system • TIMESTAMP (12) WITHOUT