I have a need to build a system that fetches data from an Amazon pgdb3 and provide a constant that is used later in the transformation, which is "S_ID" here.
This is my transformation and it is giving me errors if I try to use the variable as ${S_ID} in the "Add constants" step as shown.
What do I need to do in order to make the transformation succeed?
I don't know if the Add constants step has been modified in later versions, but in my 8.2 version of PDI it doesn't allow the use of variables in the Value.
Use the Get variables step instead.
Related
I have last version of jupyterlab Version 3.0.14
in debugging mode many variables not needed exists in the right box
what are they?
I want to delete them except i, j and result.
You can adjust the variableFilters setting of the debugger to hide variable that you are not interested in; see this answer for more details.
The debugger simply shows all variables that are available at runtime in the kernel; the Python kernels (IPython and Xeus Python) come with a feature of remembering your input and output for each executed cell; it is immensely useful if you execute a cell with compute-intensive task but forget to assign the result onto a variable, for example instead of:
result = do_long_calculation()
you do:
do_long_calculation()
in the latter case you can use the IPython underscore _ variable which caches the last execution result to recover the output:
result = _
If you already overwritten the most recent output, it the previous one goes to __ and so on. Learn more about this in the output caching system documentation.
Similarly _i, _ii, etc. variables cache most recent input of cells so you can check what has been executed. See more in input caching system documentation. There are also In and Out variables which store entire execution history for your reference.
Fur the future convenience I raised the idea of allowing regular expressions to hide all variables matching a pattern here.
Using Pentaho PDI 8.3.0
I am unable to use a parameter in a REST call within a transformation. What I've done is:
Create a transformation and given it a parameter called PAGE_NR with default value 1
Create a job
Call the transformation with parameter PAGE_NR = 1
In the transformation, set up a GET request to a REST API.
In the URL field, setup the call like http://myurl.com/foo/bar?page=${PAGE_NR}
When I call this from either SoapUI or a browser it works but it always breaks when running the job. It does not seem to translate this parameter into the value, but instead passes it exactly like mentioned above.
I need this parameter because of calling the same URL but with different results. I don't know the amount of pages up front but take care of that logic later in said transformation.
Working on Linux btw. I have tried different variations of calling the parameter but nothing seems to work.
With the information given in the comments, I am willing to make an educated guess:
The REST Client step does not perform variable substitution on the URL if it comes from a field in the stream. What you can do is insert a Calculator step before the REST step with the operation "Variable substitution on string A" with your URL field as Field A.
This should give you the desired URL with page number.
I am trying to dynamically name an excel file after processing it for archiving purposes.
If I process Logistics.xlsx I want to save it as U:\Archive\${varDP}.xlsx
Resulting file name U:\Archive\20190709.xlsx
I have tried Get system variable to get the date, This works fine. I have created the field (DateProcessed). However, I am unable to Set variables varDP to DateProcessed.
Thank you
You cannot set and use a variable in the same transformation. If you want to use a variable you should have a job with two transformations: first transformation gets the date and sets the variable; second transformation can then use the variable.
The main reason for that is that all steps initialise at the same time. Therefore, when the variable is read by the step that is using it, it's probably not set yet.
For these cases of Variables usage and passing parameters, i've been forwarding this previous answer, it has a link to another answer of mine where i go step by step of how to pass parameters to another Transformation without 'Set Variables', and in the linked answerm i have sent a downloadable example.
In kettle what is output field in java script and how to use setVariable in it.I tried to set variable in it but it gave me error
The javascript step takes the input from the previous steps and can be accessed from the input field. If you want to pass the same field to the output, you need to us the output field.
Also if you want to set the variable in javascript step, you can use
setVariable("variablename","value","type");
they are two different things.
the javascript if connected in a stream , gets as input all the fields (columns)
and can manipulate them with regular javascript.
if you want a new variable that will be a part of the stream all you need to do is:
var X;
then you can write this X as output at the bottom of the step.
give it a name and use it
so if you use something like
x = fieldA + fieldB
you can use the x on the stream.
the set variables used for setting a variable in one job to use in another job
its more like global / public in programming.
if you want to learn more about it you can take my course
just click pentaho kettle tutorial there is a lesson (video) on both steps
In LaTeX, how can I define a string variable whose content is used instead of the variable in the compiled PDF?
Let's say I'm writing a tech doc on a software and I want to define the package name in the preamble or somewhere so that if its name changes, I don't have to replace it in a lot of places but only in one place.
add the following to you preamble:
\newcommand{\newCommandName}{text to insert}
Then you can just use \newCommandName{} in the text
For more info on \newcommand, see e.g. wikibooks
Example:
\documentclass{article}
\newcommand\x{30}
\begin{document}
\x
\end{document}
Output:
30
Use \def command:
\def \variable {Something that's better to use as a variable}
Be aware that \def overrides preexisting macros without any warnings and therefore can cause various subtle errors. To overcome this either use namespaced variables like my_var or fall back to \newcommand, \renewcommand commands instead.
For variables describing distances, you would use \newlength (and manipulate the values with \setlength, \addlength, \settoheight, \settolength and \settodepth).
Similarly you have access to \newcounter for things like section and figure numbers which should increment throughout the document. I've used this one in the past to provide code samples that were numbered separatly of other figures...
Also of note is \makebox which allows you to store a bit of laid-out document for later re-use (and for use with \settolength...).
If you want to use \newcommand, you can also include \usepackage{xspace} and define command by \newcommand{\newCommandName}{text to insert\xspace}.
This can allow you to just use \newCommandName rather than \newCommandName{}.
For more detail, http://www.math.tamu.edu/~harold.boas/courses/math696/why-macros.html
I think you probably want to use a token list for this purpose:
to set up the token list
\newtoks\packagename
to assign the name:
\packagename={New Name for the package}
to put the name into your output:
\the\packagename.