Open source business intelligence tutorials: Pentaho, Talend, Jasper Reports, BIRT and more.
Topics: Data Integration, Data Warehousing, Data Modeling, BI Server Setup, OLAP, Reporting, Dashboarding, Master Data Management and many more.
Thursday, December 10, 2009
Rethinking the Pentaho Report Designer Layout
Friday, December 4, 2009
- Added OLAP4J (Advanced) and Mondrian (Advanced) datasources. These datasources work exactly as the SQL (Advanced) datasource by allowing the query to be computed by a formula.
- Formulas can be used in parameters now. There are two formula types: Display-value computation for lists, and for all parameters a post-processor.
- Parameter-Support added to OLAP4J (except for members and sets)
Wednesday, December 2, 2009
Exporting Characters as UTF-8 from Ke...
- Make sure your MySQL table uses the UTF-8 encoding
- Make sure that in the database connection details in Kettle following options are set: characterEncoding=utf8, characterSetResult=utf8,useUnicode=true.
- Once you ran the ETL process and populated, don't worry if MySQL Query Studio displays the characters as an array of pipes (in this case the Cyrillic fonts are not installed). If you see question marks, well then, something is still wrong.
Tuesday, November 3, 2009
Using Parameters in Pentaho Report Designer
- Introduction
- How to define a parameter
- Additional info about the new parameter dialog
- Using parameters with database queries
- Using parameters with Metadata/MQL queries
- Using parameters with Mondrian/OLAP/MDX queries
- XPath
- Reflection/Java Method Call
- Pentaho Data Integration (Kettle)
- Scriptable
- Referencing parameters in the message field
Introduction
You wonder what all this fuss is about? Or are you one of the many who have been struggling to use parameters in your data queries?
Using parameters with Pentaho Report Designer 3.5 (PRD) and later versions is not a trivial topic. The main problem is, that for each data source the parameter definition is different. Using parameters with standard database queries is fairly easy, using it with MDX, MQL queries and other data sources is a bit more an advance topic.
We will start off with discussing the easiest implementation and then we will move on to discuss solutions for MQL and MDX queries.
How to define a parameter
PRD 3.5 is a major improvement over previous versions of this software. One of the new features is, that you can define parameters within your report, which means, that you do not have to use Xactions any more. (You can still use Xactions for more complex logic, but generally speaking, defining the parameters within your report will make your life easier).
Within the data tab in PRD you can see a section called "Parameters". Right click on it and select "Add parameter". In the dialog you can define your parameter name, define the input type (drop down menu etc.), add a data source to populate the input dialog and make the parameter mandatory. This is all fairly straight forward and easy to set up.
Note: You have to set up the parameter before you reference it in your data queries.
Additional info about the new parameter dialog
Hidden Parameters
By selecting a tiny little check-box, parameters can now be excluded from the UI-generation. The parameter itself still behaves like any other parameter and thus takes part in the formula-calculations and is part of the validation.
Parameter Validation can be loosened
When this flag is set to false, the validator will accept other values than the ones that have been specified in a list-parameter. With relaxed validation, you can easily write WHERE conditions, that accept partial matches or contain “LIKE” clauses. For the sake of security, we none-the-less default this feature to strict-checks.
Display-Formula
Every List-Parameter can now have computed display-texts. This way, you are no longer limited by what your data source can produce, and even a simple data-source like an XML file or a static table-datasource can produce better looking prompts.
Post-Processing Formula
A post-processing formula processes the parameter-input before it gets validated or passed into the report. The post-processing can either be defined on the parameter itself or can be defined as an extra field by using a hidden parameter. The computed value will still be validated by the engine and thus using formula’s does not necessarily mean you have to fear that illegal input comes through. Formulas allow you to access runtime information, like the current user’s roles or the user’s name via the ENV(..) function.
Using parameters with database queries
From PRD 3 to PRD 3.5 the way you define your parameters in a SQL query has slightly changed.You define a parameter within a SQL query like this: ${parametername}. Make sure you do not use enclosing single or double quotation marks, as PRD knows already how to display the parameter.
Example:
SELECT
*
FROM
table
WHERE
start_date <= ${my_start_date}
;
Using parameters with Metadata/MQL queries
<constraints>
<constraint>
<operator>AND</operator>
<condition>[TABLE.COLUMN] = [param:MY_PARAMETER]</condition>
</constraint>
</constraints>
Let's have a look now at how to use date parameters in MQL. Normally, if you are using a date in MQL, you would have to use DATEVALUE("2009-11-01"), but it seems that if you are using a data parameter, DATEVALUE() shouldn't be used. As Thomas (Taqua) points out "'Normally' probably refers to 'in the old days'. But in the old days, Metadata had no parametrization at all, and all the parametrization that happened in the BI-server was a simple string-manipulation exercise on the XML code that represents the query. Thats why you in reality only passed in strings and then had to convert it via a DATEVALUE function. (And of course, its just a horrible way to do parametrization, as you now have to be careful that your strings do not break the XML or even rewrite the XML for fun and profit.)"
Using parameters with Mondrian/OLAP/MDX queries
How to pass on a single value
Imagine you want to pass on a single value to the member of a simple dimension like [Login Date].[Date]. You can use a function called parameter, which basically looks like this: parameter("parametername", dimension, member default value).The member default value will be used (you guessed it) in case no parameter value is available. This is very useful if you are still designing your report in PRD.
Here is an example of using this approach:
SELECT
LastPeriods(6,Parameter("my_date",[Login Date],[Login Date].[2009-09-12]))
ON ROWS,
[Measures].[Distinct Users]
ON COLUMNS
from [Logins]
Since PRD 3.6 I've been also using the standard variable approach of ${variable} successfully:
WITH
MEMBER [Measures].[7daysago] AS
(CurrentDateMember([Date.Date Digits],
"[""Date.Date Digits""]\.[""Date Digits""]\.[yyyy-mm-dd]").Lag(7.0),
[Measures].[CTR])
MEMBER [Measures].[6daysago] AS
(CurrentDateMember([Date.Date Digits],
"[""Date.Date Digits""]\.[""Date Digits""]\.[yyyy-mm-dd]").Lag(6.0),
[Measures].[CTR])
MEMBER [Measures].[5daysago] AS
(CurrentDateMember([Date.Date Digits],
"[""Date.Date Digits""]\.[""Date Digits""]\.[yyyy-mm-dd]").Lag(5.0),
[Measures].[CTR])
MEMBER [Measures].[4daysago] AS
(CurrentDateMember([Date.Date Digits],
"[""Date.Date Digits""]\.[""Date Digits""]\.[yyyy-mm-dd]").Lag(4.0),
[Measures].[CTR])
MEMBER [Measures].[3daysago] AS
(CurrentDateMember([Date.Date Digits],
"[""Date.Date Digits""]\.[""Date Digits""]\.[yyyy-mm-dd]").Lag(3.0),
[Measures].[CTR])
MEMBER [Measures].[2daysago] AS
(CurrentDateMember([Date.Date Digits],
"[""Date.Date Digits""]\.[""Date Digits""]\.[yyyy-mm-dd]").Lag(2.0),
[Measures].[CTR])
MEMBER [Measures].[1daysago] AS
(CurrentDateMember([Date.Date Digits],
"[""Date.Date Digits""]\.[""Date Digits""]\.[yyyy-mm-dd]").Lag(1.0),
[Measures].[CTR])
SET [Period] AS
(CurrentDateMember([Date.Date Digits],
"[""Date.Date Digits""]\.[""Date Digits""]\.[yyyy-mm-dd]").Lag(7.0) : CurrentDateMember([Date.Date Digits],
"[""Date.Date Digits""]\.[""Date Digits""]\.[yyyy-mm-dd]").Lag(1.0))
MEMBER [Measures].[Period] AS
Avg([Period],
[Measures].[CTR])
MEMBER [Capsule].[Total Live Capsules] AS
SUM((FILTER([Capsule].[Capsule].Members,
(NOT ([Capsule].[Capsule].CurrentMember.Name MATCHES ".*test.*")))),([Measures].CurrentMember))
SELECT
{[Measures].[7daysago],
[Measures].[6daysago],
[Measures].[5daysago],
[Measures].[4daysago],
[Measures].[3daysago],
[Measures].[2daysago],
[Measures].[1daysago],
[Measures].[Period]}
ON COLUMNS,
NON EMPTY (UNION(({Filter({[Capsule].[Capsule].Members},
(NOT ([Capsule].[Capsule].CurrentMember.Name MATCHES ".*test.*")))} * {[Creative].Children}),
({[Capsule].[Total Live Capsules]} * {[Creative]}),
ALL))
ON ROWS
FROM [FUNNEL CUBE]
WHERE
({[Site].[${VAR_PARTNER_NAME}].[UNKNOWN].[${VAR_CLIENT_NAME}]} * {[Bucket Type].[TREATMENT]} * {[Ad Type].[Ad Type].[Retargeted]})
How to pass on multiple values
It is very likely that you have to populate nearly the whole dimension, i.e. [Login Date.Monthly Calendar].[Monthly Calendar All].[Year].[Quarter].[Month].[Day] which would look like this: [Login Date.Monthly Calendar].[Monthly Calendar All].[2009].[Q3].[Jul].[2].More info
Beginning with Milestone 2 of the Pentaho Report-Designer 3.6,we now support parameter injection via the${parameter} syntax. Parameter values injected via that syntax will not be checked in any way, so it is the designer's responsibility to ensure that everything is quoted correctly to cause no harm or to break the query. With great powers comes great responsibility.
The ${parameter} syntax for MDX is not just a toString() conversion. It follows the MessageFormat syntax and thus allows to format Date and Number objects properly before inserting them into the MDX query. An extended format rule allows to produce quoted MDX-string literals by specifying the subformat <string. These strings start and end with a double-quote and all double-quote characters found in the original string get escaped according to the MDX grammar.
So now I can finally answer the question on how to parametrize a Date-Axis from a Date-parameter. To produce a member string like [2009].[10].[4] from a parameter called dateparam use[${dateparam,date,"yyyy"}].[${dateparam,date,"MM"}].[${dateparam,date,"dd"}] in your MDX query.
I still haven't found out how to do the same with the PARAMETER function.
Support for the PARAMETER function will remain there (as in theory it is a good idea to have prepared/explicit parameter).
You can test this functionality with either the latest CI build or with the upcoming Milestone 2 of the Report-Designer 3.6.
by the reporting engine (if the parameter is a java.lang.String, otherwise we will throw a very visible exception). You are using a StrToMember which probably does not like the "{..}" syntax of the sets. Try a StrToSet instead, if you intend to pass a set.
You can also skip the parameter function and use the classical ${...} parametrization syntax (PRD 3.6 or newer), which performs a simple replacement on the MDX string. To prevent code injections you can specify a subformat along with those parameters: ${param} will include the parameter without any modification.
${param,string} will quote the parameter value as MDX string (slap double quotes around it and escape all inner double quote chars)
${param,formattype,formatstyle} will treat the parameter as a message format request, so that you can format numbers, dates and so on properly.
For the grammar of formattype and formatstyle have a look at http://download.oracle.com/doc
How to create a parameter for a set (posted by Bill W.):
select [selectedset] ON COLUMNS,
from [Monthly Influenza Summary]
I am using PRD parameters to get the set of customers in a multi-select, then I turn that set into a formatted array which I use in the query. The basics are there now.
XPath
- also uses the ${param} syntax to have parameters. (Same syntax as JDBC)
Reflection/Java Method Call
- parameters are given as plain names, no special encoding needed.
- parameter are separated by comma
- if the parameter-name itself contains a comma or double-quotes, quote the parameter-name by
- enclosing it in double quotes
- any inner double-quote character must be quoted by another double quote. (Parameter name : Joe"A" becomes "Joe""A""")
Pentaho Data Integration (Kettle)
- Parameter are declared explicitly
- PDI only accepts strings, so if the parameter is no string, then it will be converted via "toString()"
- KTR file needs to declare the parameter and arguments
Scriptable
- Scripts have a "dataRow" variable that implements org.pentaho.reporting.engine.classic.core.DataRow.
- Scripts also have access to
- "configuration" (org.pentaho.reporting.libraries.base.config.Configuration)
- "resourceBundleFactory" (org.pentaho.reporting.engine.classic.core.ResourceBundleFactory)
- "resourceManager" (org.pentaho.reporting.libraries.resourceloader.ResourceManager)
- "contextKey" (org.pentaho.reporting.libraries.resourceloader.ResourceKey)
Referencing parameters in the message field
Tuesday, October 27, 2009
Send Pentaho Report By Email
The Pentaho Report Designer 3.5 brought along some important improvements. If you set up Xactions before that sent out reports by email, there are some slight changes now that you want to be aware of.
In my case I prepared a report that uses a MDX query as source, which automatically selects the last 5 days of data. The report doesn't use an input, so it is fairly easy to integrate into an Xaction.
My idea is to have basically a simplified version of the report in the email body and the full report with a chart as attachment. For the report, that I intend to have in the email body, I have to make sure that the CSS is not an external file. You can do this by going to File/Configururation in the Report Designer 3.5 and setting InlineStyle to true in output-table-html.
I set up following steps in the Xaction (Pentaho Report Designer 3.5):
- Message template for email subject name. Define an output name.
- Message template for file attachment name. Define an output name.
- Message template for email text. Define an output name.
- Pentaho Report XLS: In this step we create the Excel file for the attachment. Tag "Use Content Repository". Define "Report XLS" as output-name. Make sure you set the output-format to application/vnd.ms-excel
- Pentaho Report HTML: Set to output-format to text/html. Tag "Use Content Repository". We will use this output for the email html body. Define "Report-HTML" as output-name.
- Now drag and drop both Report-HTML and Report-XLS into the output folder in the report-outputs area. For each of them, add a output destination. At this point it doesn't matter which destination you choose.
- Now we have to edit the XML directly, hence change to the XML view. Look for the outputs that you defined earlier, and if you defined i.e. a file destination beforehand, then replace the <file></file> by <contentrepo></contentrepo>.
- Now add the email step. Fill out the fields and reference the parameters that we define earlier on where applicable. In example: Add a parameter to HTML message: "Report-HTML".
Friday, October 9, 2009
Current date function on Mondrian
- your time dimension, i.e. [Login Time]
- the mapping format, i.e. '["Login Time"]\.[yyyy]\.["Q"q]\.[m]\.[d]', which will resolve to [Login Time].[2009].[Q4].[10].[7]
- mapping method (optional): BEFORE, AFTER or EXACT
Formatting Strings as used by Mondrian (which differs in some cases to the ones mentioned in the VB Docu):
yyyy Year
q Quarter
m Month
y Day of year d Day
w Weekday ww Week
h Hour
n Minute s Second
Mapping [2009-10-12] date format:
select {CurrentDateMember([Login Date], '[yyyy-mm-dd]').Lag(3.0)} ON COLUMNS,
{[Login Channel].[All Login Channels]} ON ROWS
from [Logins]
WHERE
{[Measures].[Distinct Users]} For some reason, although the documentation clearly states "MM" for
month number with a leading 0, only "mm" will work. It is a good idea
to check the mondrian.log in case you experience errors, as you will
see there if the translation works (i.e.: if the Mondrian log shows
[2009-MM-09], you know that the month number was not translated).
The above example was for a dimension with one hierarchy only. Please find below an example with a dimension with more than one hierarchy:
SELECT
CurrentDateMember([Date].[Date],'[Date]\.[Date]\.[yyyy-mm-dd]').Lag(357.0) ON COLUMNS,
NON EMPTY {Hierarchize({[Measures].[Sales]})} ON ROWS
FROM [Sales]
Mapping [2009].[4].[October].[12] date format:
select {CurrentDateMember([Login Time Monthly], '[yyyy]\.[q]\.[mmmm]\.[d]').Lag(3)} ON COLUMNS,
{[Login Channel].[All Login Channels]} ON ROWS
from [Logins]
WHERE
{[Measures].[Distinct Users]} Mapping [2009].[41].[6] date format:
select {CurrentDateMember([Login Time Weekly], '["Login Time Weekly"]\.[yyyy]\.[ww]\.[w]').Lag(3)} ON COLUMNS,
{[Login Channel].[All Login Channels]} ON ROWS
from [Logins]
WHERE
{[Measures].[Distinct Users]}
So when should you now mention the dimension in the formating string? If you avoid mentioning it, Mondrian will have to search for the existence of the various members within all the dimensions, which takes processing time. If you have only one date dimension, then you could theoretically not mention the dimension string, if you have more, then there is no way around it.
Imagine now, we want to have a monthly and weekly summary of the last 6 periods. So how do we approach this?
Last 6 weeks:select {
CurrentDateMember([Login Time Weekly], '["Login Time Weekly"]\.[yyyy]\.[ww]').Lag(6) :
CurrentDateMember([Login Time Weekly], '["Login Time Weekly"]\.[yyyy]\.[ww]')
} ON COLUMNS,
{[Login Channel].[All Login Channels]} ON ROWS
from [Logins]
WHERE
{[Measures].[Distinct Users]}
Please keep in mind that here our time dimension looks like this: [year].[week].[day]
Last 6 months:
select {
CurrentDateMember([Login Time Monthly], '["Login Time Monthly"]\.[yyyy]\.[q]\.[mmmm]').Lag(6) :
CurrentDateMember([Login Time Monthly], '["Login Time Monthly"]\.[yyyy]\.[q]\.[mmmm]')
} ON COLUMNS,
{[Login Channel].[All Login Channels]} ON ROWS
from [Logins]
WHERE
{[Measures].[Distinct Users]}
Please keep in mind that here our time dimension looks like this: [year].[quarter].[month].[day]
I hope that this tutorial showed you the power of CurrentDateTime(). It is a very useful function, especially if you have to do a lot of analysis across time. It tooks me quite some time to use this function correctly (especially as there are not many examples), so I hope you can implement it within 5 minutes.
One final example: The VB format string for day of week is w. This will return 1 for Sunday - which is based on the US week format. So for those living in Europe, where the week starts on a Monday, how do you handle this? Just add 1 to the lag function:
CurrentDateMember([Date.Weekly Calendar],'["Date.Weekly Calendar"]\.[yyyy]\.[ww]\.[w]').Lag(3+1)
Wednesday, October 7, 2009
How to change the Pentaho Login Screen
Have you ever wondered how to get rid of the sample users in the Pentaho BI Server login box? Tom Barber pointed out a simple solution recently on the Pentaho forum that was originally posted by Paul Stoellenberger:
biserver-ce\tomcat\webapps\pentaho\mantleLogin\loginsetting s.properties
there is an option:
#showUsersList=true
change that to
showUsersList=false
Thursday, October 1, 2009
Converting binary data type to string in...
Sometimes you might come across data that is store in in binary form in a table. To convert this data you chose one of the following approaches:
Convert directly using SQL in the database input step
One quick method would be to use the CONVERT or CAST function (test which one works best for you):
Select Values ... step
Modified Java Script Value Step
If you have to import the binary data into Kettle, you can use this approach:var string = new Packages.java.lang.String(yourField, "UTF-8");
Setting up an "All" Parameter
We do the same for the channels query. Please keep in mind that UNION will remove any duplicates. If you are sure that you have no duplicates, you can use UNION ALL to improve the performance.
As some of you might use Oracle as well, a user named "zulu" from the pentaho forum pointed out that:
"Not sure if this helps you now, but depending on your SQL dialect, a
NULL (meaning nothing) is treated differently to a "NULL" string.
In Oracle your predicate could be:
WHERE (${media} IS NULL OR media=${media}).
Oracle applies "lazy" logic, so if your Media parameter is not
completed by the user (meaning it "IS NULL"), the condition will not
even check the "media=${media}" part."
Just a remark from my side: My original post included a query like this one "(media = ${media} OR 'All Media' = ${media})"
You can find the original post here.
Update 2012-05-30: Somebody asked me how to achieve the same with mulitselect parameters. Here is the approach that works for me (It's a different dataset, but you get the idea):
SELECT
`city_sales`.`date`,
`city_sales`.`continent`,
`city_sales`.`country`,
`city_sales`.`city`,
`city_sales`.`revenue`
FROM
`city_sales`
WHERE
(city IN (${CITY}) OR "All cities" IN (${CITY}))
Note: I defined the CITY parameter as type STRING.
Tuesday, September 29, 2009
Pentaho Report Designer 3.5: Not mand...
When creating parameters in Pentaho Report Designer 3.5, you can definie if the paramater is mandatory or not.
Imagine we have a query like this one to feed our report:
SELECT
*
FROM
table
WHERE
channel = ${channel} AND
media = ${media}
;
I define two parameters for this report: channel and media. The end user will be able to choose a value for these parameters once they call the report. In the query you define the parameter like this: ${parameter_name}. This is fairly easy so far, but how do we configure the report if we want to allow the users to choose either one media value or non (=showing all media types)?
This is not difficult to implement, if you know how to do it. Basically, you have to change your query to this:
SELECT
*
FROM
table
WHERE
channel = ${channel} AND
(media = ${media} OR 0 = IFNULL(${media},0)
;
Basically, if the user doesn't choose any value for media, the media value will be set to NULL (as in "no value"). So I changed the query to include "(media = ${media} OR 0 = IFNULL(${media},0)", which basically says: If there is a media value, apply it, if not, return all the media types (=no filter). So depending on which part is TRUE, the query result will change!
Now this is a fairly wonderful way to implement this. The only problems are that the Null value/No filter will be only available when you call the report in the first go, once you changed the Media to "TV" in example, the drop down menu (or whatever display type you chose) doens't offer a NULL value any more. Also, it would be great to be able to rename the NULL value for the end user individually, in example to "All Media Types".
Monday, September 28, 2009
Pentaho Kettle: Using Full Outer Join
- IF input data table 1 NOT EMPTY AND input data table 2 EMPTY THEN output only data of table 1.
- IF input data table 2 NOT EMPTY AND input data table 1 EMPTY THEN output only data of table 2.
- IF input data table 1 NOT EMPTY AND input data table 2 NOT EMPTY THEN JOIN everything and output it.
- Drag and drop two "table input" steps into the working area and define the settings. Our query looks like this:For table1:GROUP BY 1,2
SELECT
date,
service_name,
COUNT(*) AS count
FROM
table1
For table2:
SELECT
date,
service_name,
COUNT(*) AS count,
SUM(rev) AS rev_sum
FROM
table2
GROUP BY 1,2 - For each of them add a sort step and connect them with the table input. Make sure you sort the relevant fields in ascending order (in our case this is date and service_name).
- Drag and drop a Join step on the working area, connect them with the two sort steps and then define the two sort steps as input.
- date and data_1 and
- service_name and service_name_1
Saturday, September 26, 2009
Full Review of "Pentaho Reporting 3.5 for Java Developers"
Overall, it is an excellent book. It guides you through various tutorials on how to create more complex reports. All the tutorials are fairly easy to follow. Some chapters of the book give a very detailled description of the available functionality and settings, which serves as an excellent reference.
Conclusion: I really enjoyed reading this book. From my point of view Will Gorman provides an interesting overview of Pentaho Reporting. If you are one of those users that are not familiar with Java and just want to get a general overview of Pentaho Reporting, then this book will also be a good ressource as well (just skip some of the pages then that describe the Java integration).
I hope that there will be a Part II of this book, as I certainly would have liked to know more about adding OLAP and Metadata sources to the report and parameterizing them.
Wednesday, September 23, 2009
New books arrived
I think I am going to start with the Pentaho Reporting book, so that I can post a review here quite soon. It was a tough choice, as all the books sound very interesting.
Thursday, September 17, 2009
Review "Pentaho Reporting 3.5 for Java Developers" Books Chapter 6
Wednesday, September 16, 2009
Review coming soon ...
I've quite some books to read currently about OLAP and Data Warehouse Design, but I'll try to speed up to provide a review about this exciting new book in the next few months. So stay tuned!
Saturday, September 12, 2009
New Books on Pentaho
Another book was published recently as well, called "Pentaho Reporting 3.5 for Java Developers" by Will Gorman, a long term Pentaho developer. This book will provide you everything you need to know about Pentaho Reporting 3.5. I've already ordered this books and I am quite looking forward to read them!
Friday, July 24, 2009
The 10 Seconds Pentaho Metadata Editor Tutorial
Quick Step By Step Guide
Specifying JNDI and adding the JDBC driver
- Define a JDNI Connection. You have to use the same JNDI connection as you specified on the BI Server (in the Pentaho Administration Console).The JDBC details can be specified in the jdbc.properties file in the following directory:<pme-root-dir>/simple-jndi
Add the following (amend to your requirements):dwh/type=javax.sql.DataSource
dwh/driver=com.mysql.jdbc.Driver
dwh/url=jdbc:mysql://localhost:3306/pentaho
dwh/user=root
dwh/password=The first part before the forward slash is the JDNI name (so in this case dwh). - Check if the required JDBC driver is installed under<pme-root-dir>/libext/JDBC
If not, download the JDBC driver from your vendor’s website and copy the jar file into this folder.
Importing the physical tables
- Start PME by running the following command in the PME root directory:sh ./metadata-editor.sh
- Click on File > Save and specify a good name for your metadata model.
- Right click on Connections on the top left hand side and choose New Connection .... Define your connection details, make sure you choose JNDI in the Access selection and specify the same JNDI name in the Settings section as you originally specified in the jdbc.properties file.
Some interesting options are found in the Advanced section: If you work with a database like PostgreSQL or Oracle that support proper schemata, you can define the default schema to use here. Also, if you have columns of type boolean you can also enable support for them:
After entering all the details, click the Test button to make sure that your connection details are correct. Once you get a successful return message, click OK. - Right click on the database connection you used created choose Import Tables:
- Expand the database node (dwh in the screenshot below) so that you can see all the imported tables:
- Specify table properties: Double click on each table to specify various settings. In example specify if it is a fact or dimensional table. For measures configure as well the aggregation type. If you want to add calculated fields, it's time to do so now: Double click on the respective table. Once the window is open, click on the + icon. Give the field a new name (i.e. PC_Amount_of_users). Define the aggregation type (i.e. Count). Define Data Type. If you don't know the length and precision yet, set it to -1. Define the formula (if you have just a simple count or sum, then only write the name of the column in there). That's it. (Field type can stay on "other").
In the formula field you can use database specific functions as well (i.e. "YEAR(date)"). In this case you have to click on "Is formula exact?".
You can add other properties like text alignment or date mask by clicking on the + icon.
The disadvantage of this approach is that you might end up using functions which are specific to your database, so the model will not be that easily portable to other DBs (in case you ever have to migrate it).
Defining a business model
- Right click on Business Model and select New Business Model. Name it etc.
- Drag and drop the tables onto the main working area.
- Double click on the table and go to Model Descriptor. If the type is incorrectly set (or not applicable for this model) click on the overwrite icon and define the respective table type (fact or dimension). Click OK.
- In order to create relationships between tables, select the two tables while pressing down the CTRL key and then right click on the last table and choose New Relationship:
Another way to do this, although not that convenient, is to right click on the work area and choose New Relationship:
Create a business view
- Once the business tables and relationships are established, we can create the business view. Right click on Business View and select New Category. An easier way to do this is to choose Tools > Manage Categories (or right click the Category Editor icon in the toolbar). This will bring up the Category Editor dialog: Just click the + icon to add new categories. Define Categories, i.e. Date, Measures, Countries etc. Categories are basically buckets that help you organize the various business columns.
- Next we want to assign business columns to each category. If you created your categories in the tree view, right click on Business View and choose Manage Categories. Once in the Category Editor, use the arrows to move the fields into the categories.
Testing the metadata model
Publish the metadata model to the Pentaho BI Server
- You have an account on the BI server
- The publisher password on the BI Server is set up and you know it.
- You know the name of the solution folder that you should publish the model to.
- The URL to publish to is something like http://localhost:8080/pentaho/RepositoryFilePublisher
Make sure you have RepositoryFilePublisher at the end of this URL!
Tips and tricks
Make use of Concepts
Referencing the same table more than once
How to create formulas
How to implement data security
- Click on your business model. Go to Tools > Security and import the roles from the Pentaho BI Server by entering following URL (amend if necessary):http://localhost:8080/pentaho/ServiceAction
This will allow you to restrict the data for certain roles. If the connection works ok, you will see an XML extract of the roles definition. - Go to your Business Model (this is one hierarchy below Business Models and has a brown briefcase symbol next to it) and right click, choose Edit. It is important that this is implemented on this level as otherwise it won't work.
- In the Metadata Security section add all the users/groups that you want to allow access. Assign the Update right to users that can save and edit their ad-hoc reports.
Also, if one user/group should have access to everything, you have to set the constraint to TRUE().