I know that java method can be called using database triggers in oracledb. I am new to cassandra and I want to get a similar functionality in cassandra. Would it be possible to call a specific methods using cassandra triggers or is there any way to achieve it? Any help is appreciated.
Yes, is possible, check CREATE TRIGGER for details.
Basically, when you will define the trigger you specify the class to load. This has to implement the ITrigger interface. You JAR files needs to be placed in the triggers folder on each node.
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I am using PostgreSQL with sequelize on Javascript project. It is about managing project schedule and I want to update my data on specific condition. For example
There is one Project with 'due_date' and 'current_status'.
If I set 'due_date' then 'current_status' become 'ongoing'.
When current date passes 'due_date', then 'current_status' should become 'delayed'.
I want to make step 3 automatically, but I have no idea where to handle. Currently I am looking for hooks but I can not find any hooks that can satisfy it. Is there any solution for this?
You will need to schedule a job to actively look for rows that need updating.
The job can be fired by some external scheduler (e.g. cron) or by the pg_cron extension if you're able to install it.
Quartz.net and me don't seem to think the same way. Please help.
I'll have Quartz running as a Windows Service.
I'll have an Ado Jobstore setup on my SQL server.
I'll have the connection string setup that allows Quartz to access the jobstore.
I'll have a trigger job data map (stored in the jobstore?).
I see that I can set a Job-name, and can have Job Data Map key/value pairs that I can store for example a stored proc name and maybe a param. So far so good. I also see that I can write code that will implement iJob and in it grab the key/values from the context. My code could then call the stored proc with standard ADO code. I could do a similar thing with a webservice name and param, where my custom code would call the service.
Here are my questions:
1) Do I really have to create a separate piece of code to execute the stored proc or web service? I would think something as sophisticated as Quartz would be able to "natively" handle calls to stored procs, web services, maybe execute ftp commands, etc. Am I looking for a no-code solution when I shouldn't be?
2) Assuming I do have to write my own "do the work" code, where do I put that code? Do I compile into a DLL and place it somewhere? How do I tell Quartz where to look for my DLLs? And how do I associate the Job-Name in the config with my class in my DLL? Do I just use the Job-Name setting as the actual name of my class?
Thanks!
1) Yes, you still have to write separate job classes.
2) All your class has to do is implement the IJob interface and the scheduler will pick it up. Read the documentation.
Quartz is a scheduler, it's all it does and it does it well. It does not "natively" handle calls to stored procs, web services, or ftp commands. You have to write the code to do that in your class that implements IJob and is instantiated by Quartz on the schedule you specify.
The best thing to do is to create a separate class library (DLL) that you will reference from your app which creates an instance of Quartz scheduler and provide it with a fully qualified name of the class it needs to instantiate (e.g. MyLibrary.MyNameSpace.MyClass) and it will instantiate that class on the schedule and execute your code found in the overriden Execute() method of your class...
It's that simple...
As the subject suggests I'm interested in triggering Jenkins on changes involving a pre-configured database table. For example, whenever the number of records changes I want Jenkins to perform some particular action. Is there a plugin out of the box available for this scenario?
Thank you!
Regards,
Alex
Either you have a command line client for your database or you can write a script (perl, ruby, Groovy, Java whatever) to get this functionality. This script can be executed by Jenkins. Based on the absence of information about which database we are talking about i can't give you a more detailed hint.
What database are you using?
Most of them have some kind of triggers that can be fired after table insert, update or delete.
A logical alternative to database triggers is polling: write a script that will poll the database and store the results you are watching. If they change the script can modify a file which will trigger a Jenkins build via FS Trigger plugin.
Probably the easiest way is to use a ScriptTrigger, which can easily use embedded Groovy or Shell/Windows Batch script to pool database with a query to verify state of the given data.
I am building an application in Qt/QML.
I have a table view of the database (PostgreSQL).
Is there a way to dynamically refresh my table if there is any change in the database.
One no-so-efficient way to do it is to keep sending periodic SQL queries.
Is there any automatic way to keep my view refreshed?
I am open to use any other Database also if required.
Qt seems to support the NOTIFY mechanism of PostgreSQL databases. Googling for it it found some bug reports, so not sure of well implemented that is. Since I've never used it, I'll have to refer you to google.
If you use QSqlTableModel (or an editable subclass of QSqlQueryModel) with QTableView, any edits made will immediately be visible.
How do you create a custom database driver to extend CodeIgniter's functionalities to other types of database systems? I'm using iRODS (www.irods.org). I have a version of the site created using MySQL, but I want to be able to change the database backend with minimal changes. Is there an easy way to add this function, like how you can add a custom library in CI? I haven't been able to find any so far.
I'm assuming you mean how do you create a custom Active Record driver for codeigniter? Otherwise I'm probably far off the mark here but:
There is no way I know of to simply extend or override the DB classes it is not a common thing. You can implement your own and patch up your CI config to use the new DB though.
Under system/database/drivers you find all the AR driver source. You would need to reimplement each function in each of the four files (may be able to skip on forge if you don't use it.)
I'd use the MySQL driver as a starting template as you mention you already use that, in which case you'll want to make sure all the features you use are re-implemented.
It sounds like a daunting task if you're not too experienced but I assure you the code is pretty simple.