Heroku Connect, detect salesforce update in postgres - postgresql

So I have an app taking advantages of Heroku Connect to sync datas between platforms.
I need to find a way to detect when an update has been made by Salesforce (or at least, when the sync has been executed). I'm using sequelize in nodejs, but of course the hooks don't work since heroku connect works directly on the DB and doesn't use the ORM.
So I'm wondering what are my options here.

The solutions that come to my mind (likely there are more):
check out the Heroku Connect system tables like _trigger_log. This table will give you an exact log of the actions HC took (updates/insert/deletes) with information about the record. Yes, you would need to poll it :)
Postgres brings it's own queue-system with LISTEN and NOTIFY. You an write your own database-trigger that will react on change in the salesforce tables, and have a listening/worker-process on the LISTEN queue in PostgreSQL.

Related

PostgreSQL - Periodically copying data from one database to another

I'm trying to set up an architecture with 2 databases, say preview and live, that have the exact same schemas. The use case is that edits can be made to the preview database and then pushed to the live database after they are vetted and approved. The production application would read from the live database.
What would be the most appropriate way to push all data from the preview database to the live database without bringing the live database down? Ideally the copy from preview to live would be an atomic transaction.
I've worked with this type of setup in MSSQL, but I'm fairly new to Postgres. So I'm open to hearing other ways to architect this (with Schemas perhaps?).
EDIT: The main reason to use separate databases is that I may need more than 1 target database (not just a single "live" database). I also may need to switch target databases on the fly without altering the source database schema.
I think what you're looking for is a "hot standby". This would be a separate instance of Postgresql, possibly on the same server but usually not, which is a near-real-time replica of the primary server.
In broad strokes, this is done by shipping the binary transaction logs from the primary server to the backup server, and then "replaying" them there. The exact mechanism for transmitting the logs may vary depending on your requirements.
Fortunately, the docs on this are excellent:
https://www.postgresql.org/docs/9.3/static/warm-standby.html
https://www.postgresql.org/docs/9.0/static/hot-standby.html

Track Database table changes with Sails.js

My Goal:
Then database table was externally changed, I want to send WebSocket notification to clients.
Question:
Is there a "native" Sails.js way to track changes in database table populated via Model?
I only dabble in sails but I'm not aware of a way. You might make a "model-listener" service that utilizes your adapter of choice's socket/channel capabilities. You'll have to start the listeners at some point via a hook or in the bootstrap file.
The problem you're going to run into is determining if the event(create, update, drop/delete) was external or sails. I'm more familiar with PGSQL and know you can provide an application name to your connection and could include it in your publish message so your listener/subscribe handler can ignore non-sails related events.
PGSQL trigger/notify/listen
Event Triggers
Notify
Listen
MongoDB
Capped Collections
Tailable Cursors
Of course waterline supports more adapters than the two I've listed here but I tried to pick the two I assume are the most popular. I know this might be the answer you had hoped for but it might give you some ideas to try.
Sorry, I'm a new poster so I'll try to provide some links in comments if it will stackoverflow will allow me.

Is there a way to enable an SQL log to see/optimize my queries using CloudSQL

I started my test of using a Google's CloudSQL instance with a desktop based application, so far I am impressed with a performance, even it is laggy, it does the job, so my next step is to see what simple modifications can do to my application most intended to reduce Access to the database and optimize if there is something more to do.
How can I do log the sql commands send to the database in order to check what queries are being sent. My app uses ODBC drivers in Windows.
Regards
What you probably want is to turn on the general log. Unfortunately, that requires SUPER privileges and that was removed some time ago (announcement). We are going to provide a way to tweak parameters like that via the Cloud SQL API. For now, the best solution is to use a setup a local server and use the logging on that one. If you really want it on production ping us on the google-cloud-sql-discuss Google group and we'll enable the SUPER for your instance.

Firebird 2.5.1 List databases in use by the server (superserver mode)

I want to write a C++ administrative app to simplify management of DBs I am in charge of. Currently, when I want to tell if there are users connected to multiple Firebird databases operated by 2 different instances of it, I have to connect to every single DB and check. That's ok, but I don't want to register every new database that is being created when i don't look, I want some way to list databases that are currently open or otherwise in use by the server. Current 2 uses of this functionality I can think of are:
Auto-inclusion in backup procedure
Application update, which require users to log off (one-look and I would be able to tell whom to kick or at least which department to call)
Firebird does not have an API to list all available databases. Technically Firebird simply doesn't know about the existence of a database until you actually connect to it.
You might be able to find all databases that are being connected to using the Trace API or the monitoring tables, but that does not exclude the possibility that other databases exist on your system.

How do you get data from a remote MySQL database into your app?

Have just finished a couple of tutorials regarding populating a SQLite database with data and then using this data within your app.
However none of these tutorials show how to connect to a remote server in order to obtain data.
QUESTION:
How do you get data from a remote MySQL database into your app??
What options do you have?
Remote access is not a good idea, you would have to allow everyone to access it since it's an app. The best way to go about this is to build a layer between your app and database. From the app you would access a server side script which does the database work and responds to your app.
Well there are methods to allow remote access to your mysql database on your server and being able to query the database remotely. I think this is the cleanest solution. Check out this link: http://www.cyberciti.biz/tips/how-do-i-enable-remote-access-to-mysql-database-server.html