1. © 2009 Wipro Ltd - Confidential ETL TESTING Handling Heterogeneous Data Formats Rajasimman Selvaraj Simanchal Sahu Tithi Mukherjee

2. © 2009 Wipro Ltd - Confidential 2 2 Agenda 3 5 GENERAL CASES OF DATA COMPARISON 1 ETL – Basic Concept 2 SOURCE & TARGET SYSTEMS Interpretation of Mapping Document 4 Creation of DSN

3. © 2009 Wipro Ltd - Confidential 3 ETL – Basic Concept

4. © 2009 Wipro Ltd - Confidential 4 4 ETL is the automated and auditable data acquisition process from heterogeneous source systems that involves one or more sub processes listed below: Data extraction Data transportation Data transformation Data consolidation Data integration Data cleaning Data loading ETL – Basic Concept

5. © 2009 Wipro Ltd - Confidential 5 5 Contd … Source System can be any application or data store that creates or stores data and acts as a data source to other systems. Will cover this topic in details later. Automation is critical without which the very purpose of ETL will be defeated. ETL is no good if processes need to be manually scheduled, executed or manually monitored. Extraction is first major step in physical implementation of ETL. Extraction initiates or triggers further downstream processes. Needless to say, once data is extracted it has to be hauled and transported to target, because the physical location of the source system might be different from the target warehouse. Data Cleansing is very essential as the data pulled from various source systems can have some unwanted data, unprintable characters, extra blank spaces, etc. This might cause some absurd result while loading the data into the Data warehouse.

6. © 2009 Wipro Ltd - Confidential 6 6 Contd … Transformation is the series of tasks that prepares the data for loading into the warehouse. Once data is secured, you have worry about its format or structure. Because it will be not be in the format needed for the target. Example the grain level, data type, might be different. Data cannot be used as it is. Some rules and functions need to be applied to transform the data. One of the purposes of ETL is to consolidate the data in a central repository or to bring it at one logical or physical place. Data can be consolidated from similar systems, different subject areas, etc. ETL must support data integration for the data coming from multiple sources and data coming at different times. This has to be seamless operation. This will avoid overwriting existing data, creating duplicate data or even worst simply unable to load the data in the target.

7. © 2009 Wipro Ltd - Confidential 7 7 Contd … Loading part of the process is critical to integration and consolidation. Loading process decides the modality of how the data is added in the warehouse or simply rejected. Methods like addition, Updating or deleting are executed at this step. What happens to the existing data? Should the old data be deleted because of new information? Or should the data be archived? Should the data be treated as additional data to the existing one? Data should be loaded with lots of care. Does that that means data loaded in the Warehouse is incorrect? What is the confidence level in the data? A data auditing process can only establish the confidence level. This auditing process normally happens after the loading of data.

8. © 2009 Wipro Ltd - Confidential 8 8 CONTD… A generic pictorial representation of ETL Process :

9. © 2009 Wipro Ltd - Confidential 9 SOURCE & Target SYSTEMS

10. © 2009 Wipro Ltd - Confidential 10 © 2009 Wipro Ltd - Confidential 10 SAP RDBMS – Oracle – SQL Server – DB2 – Teradata FLAT FILES –.TSV –.TXT –.CSV MS-ACCESS –.MDB – Temporary Storage SOURCE SYSTEMS

11. © 2009 Wipro Ltd - Confidential 11 © 2009 Wipro Ltd - Confidential 11 TARGET SYSTEMS RDBMS – Oracle – Teradata – SQL Server FLAT FILE

12. © 2009 Wipro Ltd - Confidential 12 Interpretation of Mapping Document

13. © 2009 Wipro Ltd - Confidential 13 © 2009 Wipro Ltd - Confidential 13 Mapping document is an excel sheet which acts as a reference document for the testing team to understand the data flow and based on this understanding the test scripts are prepared. A Mapping document generally provides the following information: Details about the Source and Target systems (Location, Connection, etc.) Details of Source and Target tables involved Various attributes of the Source and Target fields (Field Name, Data type, Size, etc) Dependencies between Source systems/tables for fetching the source data All transformation rules to be applied on the data before loading them into the Target tables Interpretation of Mapping Document

14. © 2009 Wipro Ltd - Confidential 14 © 2009 Wipro Ltd - Confidential 14 CONTD … A sample Mapping sheet looks like …..

15. © 2009 Wipro Ltd - Confidential 15 Creating a data source name (dsn)

16. © 2009 Wipro Ltd - Confidential 16 © 2009 Wipro Ltd - Confidential 16 Creation of DSN Step1: Go to START  RUN. Type odbcad32 and click OK. Step2: An ODBC Data Source Administrator will open in which, select system DSN and Click ADD button. Another window “create a new data source” will open.

17. © 2009 Wipro Ltd - Confidential 17 © 2009 Wipro Ltd - Confidential 17 Contd … Step3: Select SQL SERVER or “Microsoft ODBC for Oracle “from the list. Click OK. A small window will open

18. © 2009 Wipro Ltd - Confidential 18 © 2009 Wipro Ltd - Confidential 18 CONTD… Step4: Enter any name in” Data Source Name “text field. Enter your User Name for that data base. Enter the name of the server as such given in tns.ora file. Click ok

19. © 2009 Wipro Ltd - Confidential 19 General Cases of Data Comparison

20. © 2009 Wipro Ltd - Confidential 20 © 2009 Wipro Ltd - Confidential 20 General Cases of Data Migration Case-1: Source: Oracle Target: Oracle Other Tools: Edit Plus, Beyond Compare

21. © 2009 Wipro Ltd - Confidential 21 © 2009 Wipro Ltd - Confidential 21 CONTD… Executing the Source Query in PL/SQL Developer

22. © 2009 Wipro Ltd - Confidential 22 © 2009 Wipro Ltd - Confidential 22 CONTD… Executing the Target Query in PL/SQL Developer

23. © 2009 Wipro Ltd - Confidential 23 © 2009 Wipro Ltd - Confidential 23 Methods of comparing the data Excel Macro or third party tool verification SRC: Select * From (SELECT VNDR_KEY, NVL2(STR_ADDR,ltrim(rtrim(STR_ADDR), NVL2(PO_BOX,'PO Box'||' '||ltrim(rtrim(PO_BOX)),ltrim(rtrim(STR_ADDR)))) FROM DW_R0001_T.VNDR V WHERE VNDR_KEY >= '0000100000' AND VNDR_KEY < '0000400000' AND DEL_F is NULL Order by VNDR_KEY) SRC_VALUE TGT: Select * From (SELECT VNDR_NUM, STR_ADDR FROM AMB_CARE_T.MSS_VENDOR_MAST_STG Order BY VNDR_NUM) TGT_VALUE

24. © 2009 Wipro Ltd - Confidential 24 © 2009 Wipro Ltd - Confidential 24 CONTD… Using MINUS Select * From (SELECT VNDR_KEY, NVL2(STR_ADDR,ltrim(rtrim(STR_ADDR), NVL2(PO_BOX,'PO Box'||' '||ltrim(rtrim(PO_BOX)),ltrim(rtrim(STR_ADDR)))) FROM DW_R0001_T.VNDR V WHERE VNDR_KEY >= '0000100000' AND VNDR_KEY < '0000400000' AND DEL_F is NULL Order by VNDR_KEY) SRC_VALUE MINUS Select * From (SELECT VNDR_NUM, STR_ADDR FROM AMB_CARE_T.MSS_VENDOR_MAST_STG Order BY VNDR_NUM) TGT_VALUE

25. © 2009 Wipro Ltd - Confidential 25 © 2009 Wipro Ltd - Confidential 25 CONTD… Using Full Outer Join Select SRC.VNDR_KEY AS SRC_VNDR_KEY, TGT.VNDR_NUM AS TGT_VNDR_NUM, SRC. STR_ADDR AS SRC_ STR_ADDR, TGT. STR_ADDR AS TGT_ STR_ADDR From (SELECT VNDR_KEY, NVL2(STR_ADDR,ltrim(rtrim(STR_ADDR), NVL2(PO_BOX,'PO Box'||' '||ltrim(rtrim(PO_BOX)),ltrim(rtrim(STR_ADDR)))) AS STR_ADDR FROM DW_R0001_T.VNDR V WHERE VNDR_KEY >= '0000100000' AND VNDR_KEY < '0000400000' AND DEL_F is NULL Order by VNDR_KEY) SRC FULL OUTER JOIN Select * From (SELECT VNDR_NUM, STR_ADDR FROM AMB_CARE_T.MSS_VENDOR_MAST_STG Order BY VNDR_NUM) TGT ON ltrim(rtrim(SRC.VNDR_KEY)) = TGT.VNDR_NUM OR (ltrim(rtrim(SRC.VNDR_KEY) ) IS NULL AND TGT.VNDR_NUM IS NULL) AND ltrim(rtrim(SRC. STR_ADDR) ) = TGT. STR_ADDR OR (ltrim(rtrim(SRC. STR_ADDR) ) IS NULL AND TGT. STR_ADDR IS NULL)

26. © 2009 Wipro Ltd - Confidential 26 © 2009 Wipro Ltd - Confidential 26 CONTD… Case-2: Source: RDBMS\Flat file Target: SQL Server Other Tools: Edit Plus, Beyond Compare, VIM Editor

27. © 2009 Wipro Ltd - Confidential 27 © 2009 Wipro Ltd - Confidential 27 Importing Oracle Table into Access Step1: Click the menu “NEW” and a window by name “NEW TABLE” will open. Select the option “import table” as shown in the slide. Click OK

28. © 2009 Wipro Ltd - Confidential 28 © 2009 Wipro Ltd - Confidential 28 CONTD… Step2: A window named “Import” will open. In that select “ODBC Data Sources” from the drop down list of “Files of Type” combo box. Click ok

29. © 2009 Wipro Ltd - Confidential 29 © 2009 Wipro Ltd - Confidential 29 CONTD… Step3:”Select Data Source” window will open. Select “Machine Data Source” tab. Select the name of the data source, from which you want to import a table. Click Ok

30. © 2009 Wipro Ltd - Confidential 30 © 2009 Wipro Ltd - Confidential 30 CONTD… Step4: A login window will open. Enter your login credentials for that database. Click ok.

31. © 2009 Wipro Ltd - Confidential 31 © 2009 Wipro Ltd - Confidential 31 CONTD… Step5: A window name “Import Objects” will open. Select the table from the list. Click “OK” and the table will start getting imported into MS_ACCESS..

32. © 2009 Wipro Ltd - Confidential 32 © 2009 Wipro Ltd - Confidential 32 Importing flat-file into Access After clicking import table menu in MS_ACCESS, the following screen appears Select the appropriate text file and click “IMPORT”

33. © 2009 Wipro Ltd - Confidential 33 © 2009 Wipro Ltd - Confidential 33 CONTD… Select the appropriate radio button based on whether the text file is delimited or fixed width

34. © 2009 Wipro Ltd - Confidential 34 © 2009 Wipro Ltd - Confidential 34 CONTD… Select proper radio button based on the type of delimitation of the flat file. For flat files having the column names as first record, select the check box-‘First Row Contains Field Names’

35. © 2009 Wipro Ltd - Confidential 35 © 2009 Wipro Ltd - Confidential 35 CONTD… Select new table

36. © 2009 Wipro Ltd - Confidential 36 © 2009 Wipro Ltd - Confidential 36 CONTD… Click on individual columns and give the name and data type of the field in the designated text fields. Click Finish once you are done and the table will be imported

37. © 2009 Wipro Ltd - Confidential 37 © 2009 Wipro Ltd - Confidential 37 Exporting table from ACCESS to SQL Server Step1: Right click on the Table name in MS ACCESS and select export from the pop-up menu. A browse window will open

38. © 2009 Wipro Ltd - Confidential 38 © 2009 Wipro Ltd - Confidential 38 CONTD… Step2: Select ODBC Databases from the “save as type” combo box. A small window with a table name text field will open. You may keep the table name as it is or rename it by entering the desired table name in the text field. Click OK.

39. © 2009 Wipro Ltd - Confidential 39 © 2009 Wipro Ltd - Confidential 39 CONTD…

40. © 2009 Wipro Ltd - Confidential 40 © 2009 Wipro Ltd - Confidential 40 CONTD… Step3: A “Select Data Source” window will open. Go to “machine data source” tab and select the sql server database DSN name from the available list, and click “OK” and the table will start getting transferred from MS ACCESS to Sql Server. Step4: Login into Sql server and refresh the database to which you have exported a table. Now you will find the table in sql server.

41. © 2009 Wipro Ltd - Confidential 41 © 2009 Wipro Ltd - Confidential 41 Methods of comparing the data Using EXCEPT Select * From (SELECT VNDR_KEY, NVL2(STR_ADDR,ltrim(rtrim(STR_ADDR), NVL2(PO_BOX,'PO Box'||' '||ltrim(rtrim(PO_BOX)),ltrim(rtrim(STR_ADDR)))) FROM DW_R0001_T.VNDR V WHERE VNDR_KEY >= '0000100000' AND VNDR_KEY < '0000400000' AND DEL_F is NULL Order by VNDR_KEY) SRC_VALUE EXCEPT Select * From (SELECT VNDR_NUM, STR_ADDR FROM AMB_CARE_T.MSS_VENDOR_MAST_STG Order BY VNDR_NUM) TGT_VALUE Note: Except works in SQL SERVER 2005 but does not work in SQL SERVER 2000.

42. © 2009 Wipro Ltd - Confidential 42 © 2009 Wipro Ltd - Confidential 42 CONTD… Using Full Outer Join Select SRC.VNDR_KEY AS SRC_VNDR_KEY, TGT.VNDR_NUM AS TGT_VNDR_NUM, SRC. STR_ADDR AS SRC_ STR_ADDR, TGT. STR_ADDR AS TGT_ STR_ADDR From (SELECT VNDR_KEY, NVL2(STR_ADDR,ltrim(rtrim(STR_ADDR)), NVL2(PO_BOX,'PO Box'||' '||ltrim(rtrim(PO_BOX)),ltrim(rtrim(STR_ADDR)))) AS STR_ADDR FROM DW_R0001_T.VNDR V WHERE VNDR_KEY >= '0000100000' AND VNDR_KEY < '0000400000' AND DEL_F is NULL Order by VNDR_KEY) SRC FULL OUTER JOIN Select * From (SELECT VNDR_NUM, STR_ADDR FROM AMB_CARE_T.MSS_VENDOR_MAST_STG Order BY VNDR_NUM) TGT ON ltrim(rtrim(SRC.VNDR_KEY)) = TGT.VNDR_NUM OR (ltrim(rtrim(SRC.VNDR_KEY)) IS NULL AND TGT.VNDR_NUM IS NULL) AND ltrim(rtrim(SRC. STR_ADDR)) = TGT. STR_ADDR OR (ltrim(rtrim(SRC. STR_ADDR)) IS NULL AND TGT. STR_ADDR IS NULL)

43. © 2009 Wipro Ltd - Confidential 43 © 2009 Wipro Ltd - Confidential 43 CONTD … Case-3: Source: SAP Target: Oracle Other Tools: Edit Plus, Beyond Compare, VIM Editor

44. © 2009 Wipro Ltd - Confidential 44 © 2009 Wipro Ltd - Confidential 44 CONTD… Login Screen :

45. © 2009 Wipro Ltd - Confidential 45 © 2009 Wipro Ltd - Confidential 45 CONTD… Querying for the table you need to fetch data from:

46. © 2009 Wipro Ltd - Confidential 46 © 2009 Wipro Ltd - Confidential 46 CONTD… Finding the total number of records in the table:

47. © 2009 Wipro Ltd - Confidential 47 © 2009 Wipro Ltd - Confidential 47 CONTD… Choosing the fields to be displayed:

48. © 2009 Wipro Ltd - Confidential 48 © 2009 Wipro Ltd - Confidential 48 CONTD… By Default all the fields will be checked

49. © 2009 Wipro Ltd - Confidential 49 © 2009 Wipro Ltd - Confidential 49 CONTD… Uncheck the fields which are not required:

50. © 2009 Wipro Ltd - Confidential 50 © 2009 Wipro Ltd - Confidential 50 CONTD… Number of rows and columns to be fetched:

51. © 2009 Wipro Ltd - Confidential 51 © 2009 Wipro Ltd - Confidential 51 CONTD… Displaying the output:

52. © 2009 Wipro Ltd - Confidential 52 © 2009 Wipro Ltd - Confidential 52 CONTD… Selecting the records:

53. © 2009 Wipro Ltd - Confidential 53 © 2009 Wipro Ltd - Confidential 53 CONTD… Downloading or Exporting data from SAP:

54. © 2009 Wipro Ltd - Confidential 54 © 2009 Wipro Ltd - Confidential 54 CONTD… Selecting the format of the downloaded data: Note: If the result set is more than 65535 records then the data can be saved as Unconverted format and it will get saved as a “.txt” file

55. © 2009 Wipro Ltd - Confidential 55 © 2009 Wipro Ltd - Confidential 55 CONTD… Selecting the location for saving the downloaded data:

56. © 2009 Wipro Ltd - Confidential 56 © 2009 Wipro Ltd - Confidential 56 CONTD… Downloaded data displayed in spreadsheet format:

57. © 2009 Wipro Ltd - Confidential 57 © 2009 Wipro Ltd - Confidential 57 Methods of comparing the data We have two methods of comparing the SAP Data (Source) and the Oracle Data (Target): 1.If the record count is less than 65535 then we can download the SAP data and the Oracle data in.xls format. The data in the excel sheets can then be compared either with the help of Excel macro or any third party tool like Beyond Compare. 2.Alternatively, we have to download the SAP data in unconverted format (.txt) which can be imported/linked to MS ACCESS. Also the Target table (Oracle) can be imported/Linked to MS ACCESS where the Source and Target data can be compared.

58. © 2009 Wipro Ltd - Confidential 58 © 2009 Wipro Ltd - Confidential 58 Q&A QUESTIONS ??

59. © 2009 Wipro Ltd - Confidential