How can I dynamically refer the latest sequence ID from the GD project dataset when calling sequence function in ETL to connect that project?
If intending to dynamically determine from which number to restart incrementing the sequence, how should I do?
I’m afraid there is not any dynamic function to determine the latest sequence ID in a meaning of your question, but it is always possible to save this information somewhere on persistent storage on the ETL level and read it when the next ETL triggers. If the sequence is also being uploaded to the GD project as a fact, you can use the “SELECT MAX(FactName)” function.
Sincerely
Filip
Related
I am running into an issue where I have a set up a pipeline that gets a list of tables from Teradata using a Lookup activity and then passes those items to a ForEach activity that then copies the data in parallel and saves them as a gzipped file. The requirement is to essentially archive some tables that are no longer being used.
For this pipeline I am not using any partition options as most of the tables are small and I kept it to be flexible.
Pipeline
COPY activity within ForEach activity
99% of the tables ran without issues and were copied as gz files into blob storage, but two tables in particular run for long time (apprx 4 to 6 hours) without any of the data being written into a blob storage account.
Note that the image above says "Cancelled", but that was done by me. Before that I had a run time as described above, but still no data being written. This is affecting only 2 tables.
I checked with our Teradata team and those tables are not being used by any one (hence its not locked). I also looked at "Teradata Viewpoint" (admin tool) and looked at the query monitor and saw that the query was running on Teradata without issues.
Any insight would be greatly apreciated.
Onlooking issue mention it look the data size of table is more than a blob can store ( As you are not using any partition options )
Use partition option for optimize performance and hold the data
Link
Just in case someone else comes across this, the way I solved this was to create a new data store connection called "TD_Prod_datasetname". The purpose of this dataset is to not point to a specific table, but to just accept a "item().TableName" value.
This datasource contains two main values. 1st is the #dataset().TeradataName
Dataset property
I only came up with that after doing a little bit of digging in Google.
I then created a parameter called "TeradataTable" as String.
I then updated my pipeline. As above the main two activities remain the same. I have a lookup and then a ForEach Activity (where for each will get the item values):
However, in the COPY command inside the ForEach activity I updated the source. Instead of getting "item().Name" I am passing through #item().TableName:
This then enabled me to then select the "Table" option and because I am using Table instead of query I can then use the "Hash" partition. I left it blank because according to Microsoft documentation it will automatically find the Primary Key that will be used for this.
The only issue that I ran into when using this was that if you run into a table that does not have a Primary Key then this item will fail and will need to be run through either a different process or manually outside of this job.
Because of this change the previously files that just hung there and did not copy now copied successfully into our blob storage account.
Hope this helps someone else that wants to see how to create parallel copies using Teradata as a source and pass through multiple table values.
I'd like to understand if the CDC enabled IBM IMS segments and IBM DB2 table sources would be able to provide both the before and after snapshot change values (like the Oracle .OLD and .NEW values in trigger) so that both could be used for further processing.
Note:
We are supposed to retrieve these values through Informatica PowerExchange and process and push to targets.
As of now, we need to know would we be able to retrieve both before snapshot and after snapshot values from IBM DB2 and IBM IMS (.OLD and .NEW as in Oracle triggers - not an exact similar example, but mentioned just as an example to understand)
Any help is much appreciated, Thanks.
I don't believe CDC captures before data in its change messages that it compiles from the DBMS log data. It's main purpose is to issue the minimum number of commands needed to replicate the data from one database to another. You'll want to take a snapshot of your replica database prior to processing the change messages if you want to preserve the state of data such that you can query it.
Alternatively for Db2, it's probably easier to work with the temporal tables feature added in Db2 10 as that allows you to define what changes should drive a snapshot. You can then access the temporal data using a temporal SQL query.
SELECT … FROM…period specification
Example trigger with old and new referencing...
CREATE TRIGGER danny117
NO CASCADE BEFORE Update ON mylib.myfile
REFERENCING NEW AS N old as O
FOR EACH ROW
-- don't let the claim change and force upper case
--just do something automatically on update blah...
BEGIN ATOMIC
SET N.claim = ucase(O.claim);
END
w.r.t PowerExchange 9.1.0 & 9.6:
Before snapshot data can't be processed via the powerexchange for DB2 database. Recently I worked on a migration project and I thought like the Oracle CDC which uses SCN numbers there should be something for db2 to start the logger from any desired point. But to my surprise Inforamtica global support confirmed that before snapshot data can't be captured by PowerExchange.
They talk about materialize and de-materialize targets which was out of my knowledge at that time, later I found out they meant to export and import of history data.
Even if you have table with CDC enanbled, you can't capture the data before snapshot from PWX.
DB2 reads capture data from the DB2-logs which has a marking for the operation like U/I/D that's enough for PowerExchange to progress.
I have a job in talend open studio which is working fine, it conects a tMSSqlinput to a tMap then tMysqlOutput, very straight forward. My problem is that i need this job running on daily basis, but only run when a new record is created or modified...any help is highly aprecciated!
It seems that you are searching for a Change Data Capture Tool for Talend.
Unfortunately it is only available on the licenced product.
To implement your need, you do have several ways. I want to show the most popular ones.
CDC from Talend
As Corentin said correctly, you could choose to use CDC (Change Data Capture) from Talend if you use the subscription version.
CDC of MSSQL
Alternatively you can check if you can activate or use CDC in your MSSQL server. This depends on your license. If it is possible, you can use the function to identify new elements and proceed them.
Triggers
Also you can create triggers on your database (if you have access to it). For example, creating a trigger for the cases INSERT, UPDATE, DELETE would help you getting the deltas. Then you could store those records separately or their IDs.
Software driven / API
If your database is connected to a software and you have developers around, you could ask for a service which identifies records on insert / update / delete and shows them to you. This could be done e.g. in a REST interface.
Delta via ID
If the primary key is an ID and it is set to autoincrement, you could also check your MySQL table for the biggest number and only SELECT those from the source which have a bigger ID than you have already got. This depends of course from the database layout.
I have function that initialize my database create tables etc.
Now I prepare version two of the application and in this function at the end I added check for column existence and if not exist I alter table.
My question is:
To avoid checking this all the time is it good to put in UserDefaults some flag that indicate that current app is version two and if it is to avoid this code?
This seams logical to me but other opinion is always welcome ;)
You could have a version number table/column in your database which stores the schema version number. Every time you change the schema, increment the number in your application file and then run the relevant migration code to get from one schema version to another whilst updating the schema version in the database.
This answer has a handy way of tracking db schema version numbers without creating a separate table in SQLite
Yes, you can user NSUSER Default to check this. I don't think anything wrong with this.
Dear all ,
Can any one suggest me the postgres tool for linux which is used to find the
difference between the 2 given database
I tried with the apgdiff 2.3 but it gives the difference in terms of schema not the data
but I need both !
Thanks in advance !
Comparing data is not easy especially if your database is huge. I created Python program that can dump PostgreSQL data schema to file that can be easily compared via 3rd party diff programm: http://code.activestate.com/recipes/576557-dump-postgresql-db-schema-to-text/?in=user-186902
I think that this program can be extended by dumping all tables data into separate CSV files, similar to those used by PostgreSQL COPY command. Remember to add the same ORDER BY in SELECT ... queries. I have created tool that reads SELECT statements from file and saves results in separate files. This way I can manage which tables and fields I want to compare (not all fields can be used in ORDER BY, and not all are important for me). Such configuration can be easily created using "dump schema" utility.
Check out dbsolo DBSOLO. It does both object and data compares and can create a sync script based on the results. It's free to try and $99 to buy. My guess is the 99 bucks will be money well spent to avoid trying to come up with your own software to do this.
Data Compare
http://www.dbsolo.com/help/datacomp.html
Object Compare
http://www.dbsolo.com/help/compare.html
apgdiff https://www.apgdiff.com/
It's an opensource solution. I used it before for checking differences between differences in dumps. Quite useful
[EDIT]
It's for differenting by schema only