Recipes of Data Warehouse and Business Intelligence

Load a Data Source File (.csv with header, rows counter in a separate file)

into a Staging Area table with a click

The Micro ETL Foundation

• The Micro ETL Foundation is a set of ideas and solutions for Data Warehouse and Business Intelligence Projects in Oracle environment.

• It doesn’t use expensive ETL tools, but only your intelligence and ability to think, configure, build and load data using the features and the programming language of your RDBMS.

• This recipes are another easy example with different type of data source. Copying the content of the following slides with your editor and SQL Interface utility, you can reproduce this example.

• The first example is present in the slides of «Recipes 1 of Data Warehouse and Business Intelligence»

The source data file

• Get the data file to load. In this recipe we use a data file with these features:• One initial rows (is the header of the .csv file). • The reference day of the data is the current day.• No tail rows. The records number of the data file is in a separate file with «.row»

extension• Columns have «;» like separator.• The next figure is the content of the data file that we call employees1.csv

EMPLOYEE_ID FIRST_NAME LAST_NAME EMAIL PHONE_NUMBER HIRE_DATE JOB_ID SALARY COMMISSION_PCT MANAGER_ID DEPARTMENT_ID117 Sigal Tobias STOBIAS 5.151.274.564 24/07/2005 PU_CLERK 2800 114 30118 Guy Himuro GHIMURO 5.151.274.565 15/11/2006 PU_CLERK 2600 114 30119 Karen Colmenares KCOLMENA 5.151.274.566 10/08/2007 PU_CLERK 2500 114 30120 Matthew Weiss MWEISS 6.501.231.234 18/07/2004 ST_MAN 8000 100 50121 Adam Fripp AFRIPP 6.501.232.234 10/04/2005 ST_MAN 8200 100 50122 Payam Kaufling PKAUFLIN 6.501.233.234 01/05/2003 ST_MAN 7900 100 50123 Shanta Vollman SVOLLMAN 6.501.234.234 10/10/2005 ST_MAN 6500 100 50124 Kevin Mourgos KMOURGOS 6.501.235.234 16/11/2007 ST_MAN 5800 100 50125 Julia Nayer JNAYER 6.501.241.214 16/07/2005 ST_CLERK 3200 120 50126 Irene Mikkilineni IMIKKILI 6.501.241.224 28/09/2006 ST_CLERK 2700 120 50

The .row file

• Get the .row file. It is a file with only one row that contains the number of rows of the data file.

• The next figure is the content of the data file that we call employees1.row• The rows number start from 17° char for 13 chars.

BANKIN14201312310000000000010

17° char

13 char

The definition file

• Build the definition file from your documentation. It is the same of that seen in the slides of «Recipes 1 of data Warehouse and Business Intelligence»

• It has to be a «.csv» file because it must be seen by an external table.• For this example we define the minimum set of information.• COLUMN_COD will be the name of the column in the DWH.• FXV_TXT contains little transformations to be done.• COLSIZE_NUM is the size of the column in the data file.• The next is the content of the definition file that we call employees1.csv

COLUMN_ID HOST_COLUMN_COD COLUMN_COD TYPE_TXT COLSIZE_NUM FXV_TXT1 EMPLOYEE_ID EMPLOYEE_ID NUMBER (6) 6 to_number(EMPLOYEE_ID)2 FIRST_NAME FIRST_NAME VARCHAR2(20) 20 3 LAST_NAME LAST_NAME VARCHAR2(25) 25 4 EMAIL EMAIL VARCHAR2(25) 25 5 PHONE_NUMBER PHONE_NUMBER VARCHAR2(20) 20 replace(PHONE_NUMBER,'.','')6 HIRE_DATE HIRE_DATE NUMBER 10 TO_NUMBER(to_char(to_date(HIRE_DATE,'dd/mm/yyyy'),'yyyymmdd'))7 JOB_ID JOB_ID VARCHAR2(10) 10 8 SALARY SALARY NUMBER (8,2) 9 to_number(SALARY)9 COMMISSION_PCT COMMISSION_PCT NUMBER (2,2) 4 to_number(COMMISSION_PCT,'99.99')

10 MANAGER_ID MANAGER_ID NUMBER (6) 6 to_number(MANAGER_ID)11 DEPARTMENT_ID DEPARTMENT_ID NUMBER (4) 4 to_number(DEPARTMENT_ID)

The physical/logical environment

• Create two Operation System folder. The first for the data file and the second for the configuration file

• Create some Oracle directories needed for the external tables definition

• Position the data and the configuration file in the folders.

DROP DIRECTORY STA_BCK;CREATE DIRECTORY STA_BCK AS 'C:\IOS';

DROP DIRECTORY STA_LOG;CREATE DIRECTORY STA_LOG AS 'C:\IOS';

DROP DIRECTORY STA_RCV;CREATE DIRECTORY STA_RCV AS 'C:\IOS';

DROP DIRECTORY STA_CFT;CREATE DIRECTORY STA_CFT AS 'C:\IOS\CFT';

DROP DIRECTORY STA_CFT_LOG;CREATE DIRECTORY STA_CFT_LOG AS 'C:\IOS\CFT';

The source configuration table

• Create the configuration table of the data source showed in the slide 1

• It contains the unique identificator of data source (IO_ID)

• It contains the folder references (*_DIR)• It contains the information about the format

of different types of data source• Only some fields will be configured.

DROP TABLE STA_IO_CFT;CREATE TABLE STA_IO_CFT( IO_COD VARCHAR2(12), RCV_DIR VARCHAR2(30), BCK_DIR VARCHAR2(30), LOG_DIR VARCHAR2(30), HEAD_CNT NUMBER, FOO_CNT NUMBER, SEP_TXT VARCHAR2(1), IDR_NUM NUMBER, IDC_NUM NUMBER, IDS_NUM NUMBER, IDF_TXT VARCHAR2(30), EDC_NUM NUMBER, EDS_NUM NUMBER, EDF_TXT VARCHAR2(30), RCR_NUM NUMBER, RCC_NUM NUMBER, RCS_NUM NUMBER, RCF_LIKE_TXT VARCHAR2(30), FILE_LIKE_TXT VARCHAR2(60));

The load of configuration table

• Load the table according to the features of this example:

• The folders reference (rcv_dir,bck_dir,log_dir)• The name of file (file_like_txt)• The number of header (head_cnt) and footer

rows (foo_cnt).• The separator character (sep_txt). It is a csv

file with «;» separator.• The reference day is the current day, so the

related info are all null.(idr_num, idc_num, ids_num,idf_txt

• The position in the external file, with «.row» extension, of the rows number of the source data file.

INSERT INTO STA_IO_CFT (IO_COD,RCV_DIR,BCK_DIR,LOG_DIR,FILE_LIKE_TXT,HEAD_CNT,FOO_CNT,SEP_TXT,IDR_NUM,IDC_NUM,IDS_NUM,IDF_TXT,RCR_NUM,RCC_NUM,RCS_NUM,RCF_LIKE_TXT)VALUES ('employees1','STA_RCV','STA_BCK','STA_LOG','employees1.csv',1,0,';',null,null,null,null,0,17,13,'.row');

The source structure configuration table

• Create the configuration table of the data structure showed in the slide 5

• It is a metadata table• You can add others info like the column

description.

DROP TABLE STA_EMPLOYEES1_CXT;CREATE TABLE STA_EMPLOYEES1_CXT ( COLUMN_ID VARCHAR2(4), HOST_COLUMN_COD VARCHAR2(30), COLUMN_COD VARCHAR2(30), TYPE_TXT VARCHAR2(30), COLSIZE_NUM VARCHAR2(4), FXV_TXT VARCHAR2(200))ORGANIZATION EXTERNAL ( TYPE ORACLE_LOADER DEFAULT DIRECTORY STA_CFT ACCESS PARAMETERS ( RECORDS DELIMITED BY NEWLINE BADFILE STA_CFT:'EMPLOYEES1.BAD' DISCARDFILE STA_CFT:'EMPLOYEES1.DSC' LOGFILE STA_CFT:'EMPLOYEES1.LOG' SKIP 1 FIELDS TERMINATED BY';' LRTRIM MISSING FIELD VALUES ARE NULL REJECT ROWS WITH ALL NULL FIELDS ( COLUMN_ID ,HOST_COLUMN_COD ,COLUMN_COD ,TYPE_TXT ,COLSIZE_NUM ,FXV_TXT)) LOCATION (STA_CFT:'EMPLOYEES1.CSV'))REJECT LIMIT UNLIMITEDNOPARALLELNOMONITORING;

The source external table

• Create the external table linked to the source data file.

• The name and type of columns have to be the same of the configuration view.

• ROW_CNT is a useful feature of the Oracle external table to give a numbering to every row

DROP TABLE STA_EMPLOYEES1_FXT;CREATE TABLE STA_EMPLOYEES1_FXT ( EMPLOYEE_ID VARCHAR2(11), FIRST_NAME VARCHAR2(20), LAST_NAME VARCHAR2(25), EMAIL VARCHAR2(25), PHONE_NUMBER VARCHAR2(20), HIRE_DATE VARCHAR2(10), JOB_ID VARCHAR2(10), SALARY VARCHAR2(9), COMMISSION_PCT VARCHAR2(14), MANAGER_ID VARCHAR2(10), DEPARTMENT_ID VARCHAR2(13), ROW_CNT NUMBER)ORGANIZATION EXTERNAL ( TYPE ORACLE_LOADER DEFAULT DIRECTORY STA_BCK ACCESS PARAMETERS ( RECORDS DELIMITED BY NEWLINE BADFILE STA_LOG:'employees1.bad' DISCARDFILE STA_LOG:'employees1.dsc' LOGFILE STA_LOG:'employees1.log' FIELDS TERMINATED BY ';' LRTRIM MISSING FIELD VALUES ARE NULL REJECT ROWS WITH ALL NULL FIELDS ( EMPLOYEE_ID ,FIRST_NAME ,LAST_NAME ,EMAIL ,PHONE_NUMBER ,HIRE_DATE ,JOB_ID ,SALARY ,COMMISSION_PCT ,MANAGER_ID ,DEPARTMENT_ID ,ROW_CNT RECNUM)) LOCATION (STA_BCK:'employees1.csv'))REJECT LIMIT UNLIMITEDNOPARALLELNOMONITORING;

The external table to .row file

• Create the external table linked to the row file, in which there is the number of rows of the data file.

• It has only one row.• We assume that the name of the .row file is

the same of the data file with different extension.

DROP TABLE STA_EMPLOYEES1_RXT;CREATE TABLE STA_EMPLOYEES1_RXT ( ROW_TXT VARCHAR2(255))ORGANIZATION EXTERNAL ( TYPE ORACLE_LOADER DEFAULT DIRECTORY STA_BCK ACCESS PARAMETERS ( RECORDS DELIMITED BY NEWLINE BADFILE STA_LOG:'employees1.row.bad' DISCARDFILE STA_LOG:'employees1.row.dsc' LOGFILE STA_LOG:'employees1.row.log' FIELDS TERMINATED BY ';' LRTRIM MISSING FIELD VALUES ARE NULL REJECT ROWS WITH ALL NULL FIELDS ( ROW_TXT)) LOCATION (STA_BCK:'employees1.row'))REJECT LIMIT UNLIMITEDNOPARALLELNOMONITORING;

The source external view (1)

• The goal of the view is to prepare the data to load in the staging table.• It will use the useful SQL clause «with» to build the information needed. See in

details the single sub-query blocks.

– T1 = get the name of the source data file using the table of the Oracle dictionary

– T2 = get the reference day from the current sysdate.– T3 = get the declared rows number in the row file using the external table.– T4 = get the rows number using the row counter of the external table– T5 = get the header/footer rows numbers.

• You can control that the declared rows number and the rows number of the data file are the same.

The source external view (2)

CREATE OR REPLACE FORCE VIEW STA_EMPLOYEES1_FXV ASWITH T1 AS (SELECT SUBSTR(LOCATION,1,80) SOURCE_COD FROM USER_EXTERNAL_LOCATIONS WHERE TABLE_NAME = 'STA_EMPLOYEES1_FXT'),T2 AS (SELECT TO_CHAR(SYSDATE,'YYYYMMDD') DAY_KEY FROM DUAL),T3 AS (SELECT ROW_TXT FROM STA_EMPLOYEES1_RXT),T4 AS (SELECT MAX(ROW_CNT) R FROM STA_EMPLOYEES1_FXT),T5 AS (SELECT HEAD_CNT X,FOO_CNT Y,RCC_NUM RY,RCS_NUM S FROM STA_IO_CFT WHERE IO_COD = 'employees1')SELECT TO_NUMBER(EMPLOYEE_ID) EMPLOYEE_ID,FIRST_NAME FIRST_NAME,LAST_NAME LAST_NAME,EMAIL EMAIL,REPLACE(PHONE_NUMBER,'.','') PHONE_NUMBER,TO_NUMBER(TO_CHAR(TO_DATE(HIRE_DATE,'DD/MM/YYYY'),'YYYYMMDD')) HIRE_DATE,JOB_ID JOB_ID,TO_NUMBER(SALARY) SALARY,TO_NUMBER(COMMISSION_PCT,'99.99') COMMISSION_PCT,TO_NUMBER(MANAGER_ID) MANAGER_ID,TO_NUMBER(DEPARTMENT_ID) DEPARTMENT_ID,SOURCE_COD,DAY_KEY,TO_NUMBER(SUBSTR(ROW_TXT,RY,S)) ROWS_NUMFROM STA_EMPLOYEES1_FXT,T1,T2,T3,T4,T5WHERE ROW_CNT > X AND ROW_CNT <= R-Y;

• The complete SQL Statement is:

The Staging table

• The Staging table will be loaded from the previous view.

• It has the 3 technical fields to remember the name of the source data file, the reference day, and the rows num.

• The rows num can be avoided, (is the same for all records) but it can be useful for statistical checks.

DROP TABLE STA_EMPLOYEES1_STT;CREATE TABLE STA_EMPLOYEES1_STT( EMPLOYEE_ID NUMBER, FIRST_NAME VARCHAR2(20), LAST_NAME VARCHAR2(25), EMAIL VARCHAR2(25), PHONE_NUMBER VARCHAR2(20), HIRE_DATE NUMBER, JOB_ID VARCHAR2(10), SALARY NUMBER, COMMISSION_PCT NUMBER, MANAGER_ID NUMBER, DEPARTMENT_ID NUMBER, SOURCE_COD VARCHAR2(320), DAY_KEY VARCHAR2(8), ROWS_NUM NUMBER);

The final load

• I underline the following features:– All is done without ETL Tool– The only physical structure created in the DWH is the final staging table– Everything is controlled by logical structures (external tables and views)– Everything without writing any code– If you create a SQL script of this recipe, you will load the staging table with

a click

Email - massimo_cenci@yahoo.itBlog (italian/english) - http://massimocenci.blogspot.it/

• We are at the end of this recipes. Now we can do the final load with a simple SQL statement

INSERT INTO STA_EMPLOYEES1_STTSELECT * FROM STA_EMPLOYEES1_FXV;