CODEWITHSUNDEEP
pentahokettle
Richard G
Richard G

Reputation: 5683

How to work around this in/out mysql parameter bug in Kettle?

I'm using Kettle for a transformation and hitting this same issue trying to get a value for an integer based 'out' parameter in mysql, (the field should actually be bigint but I don't think it's supported in Kettle).

How to retrieve OUT parameter from MYSQL stored procedure to stream in Pentaho Data Integration (Kettle)?

I've implemented the workaround for this exact issue with decimal but I'm having a hell of a time trying to get the value firstly back into the id field (not id_1), and secondly to convert it back to an integer so it can be inserted into the database.

This is the relevant flow:

enter image description here

This is the step definition:

enter image description here

On the inbound stream coming out of lookup existing id there is already a field added called id which is a decimal that may be either a value, or null. If it's null it triggers this db procedure lookup at the filter rows step, so in other words, it will always be null at the db procedure step (and hence I can't use an in-out parameter here).

So what I want to happen is when it leaves the db procedure step, id should be populated with the value of the out parameter (ideally it would be an integer, but I can live with decimal because of the bug). But instead I get id_1 inserted into the stream.

Then further down the line, assuming I have the value in id field as a decimal, I then need to convert that back to an Integer so it can be inserted into the database without error. I don't really know how to write the javascript in Kettle though and I can't find the documentation on the language.

So my questions are twofold:

  1. Can I make the db procedure insert id back into the stream?
  2. How would I write a script(or use a step) that transforms the id (or id_1) into an Integer and places it back into the id field in the stream?

Upvotes: 3

Views: 766

Answers (1)

simar
simar

Reputation: 1822

Kettle build on Java and use JDBC driver. Let me summarize some sources and investigate issue ( I will include Postgresql, since i use it most and this information valuable for me)

First let's check size of data types: java.util.Long is 8 byte long, mysql bigint type is 8 byte long, postgresql bigint type as well 8 byte long. And by physical size they actually match except one problem. Mysql support unsigned bigint, which is out of scope java.util.Long. I assume problem appears on edge values, min and max value of java.util.Long.

Anyway i tried to reproduce (on Postgres only available at this moment to me)

Postgresql 9.4, JDBC Driver postgresql-9.4-1201-jdbc41.jar, Kettle 5.4.0, jdk7

http://forums.pentaho.com/showthread.php?48950-loosing-precision-of-BIGINT-workaround

and everything looks good. Most probably it is problem with mysql jdbc driver or it is a problem with kettle which doesn't support java.math.BigInteger. java.math.BigInteger is data type, used to work with unsigned bigint values in mysql as described in here

http://dev.mysql.com/doc/connector-j/en/connector-j-reference-type-conversions.html

About actual problem. Example of solution in here below: enter image description here

Sample csv

"id" "surname"  "name"  "birth_dt"
"1" "Gorovits"  "Alex"  "2001-01-01"
"2" "Osmani"    "Adeb"  "1998-03-06"
""  "Maiters"   "John"  "1981-07-07"
""  "Mateus"    "Angela"    "2004-04-04"
"5" "Sander"    "Tom"   "1990-05-05"

Notes:

  • DBLookup doesn't work on null values so u might need to filter rows with null values before to run DBLookup.

Upvotes: 1

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