Is there a tool to synchronise an Oracle and a Grakn database in real time? I couldn't find any information online so any help would be greatly appreciated.
I know Grakn offers GRPC through its client drivers which I'm assuming is the way to go to push things into Grakn.
And I'm aware there are triggers in the Oracle tables, but not sure if will slow down the application layer on the Oracle DB. How would this impact the performance of the BD?
Thanks!
There aren't any such tools that you can use OOTB. If you need to keep the Oracle system running then I think you've got two options:
Intercept the data as it comes in and dispatch to both Oracle and Grakn.
Find a triggering mechanism, and as you outline, read from Oracle and push the data to Grakn through its driver(s).
GRPC is built in to Grakn's drivers, and is the only way to communicate with a Grakn server. These drivers are optimised as such!
Related
I'm junior backend developer and now I'm working on a project about bank, which is a distributed system. What I knew before was that there were some message library such as ZeroMQ to realize the communication between components in a distributed system. But now, in the project, they used oracle queuing.
My colleague told me that this was better because we had no risk to lose any message to send even if processes die accidently.
My questions:Q1: If Oracle queuing is better, when should we use things like ZeroMQ?
andQ2: What is the disadvantage of Oracle queuing, comparing with ZeroMQ?
Your colleague is right here, because Oracle AQ comes with persistence and zeroMQ is in-memory. You'd use zeroMQ if you need max messages per second (millions). Price isn't a thing, because Oracle doesn't charge extra for AQ, it's even free with Oracle XE.
If your application relies on Oracle already, there are no disadvantages putting the messaging into Oracle.
I would like to use Meteor (Node.JS) to develop an application that will be used by 3,000+ concurrent users on a large size database.
I have looked at the nice examples and the idea to push changed data to the clients is very nice and very useful, but before I start the development I want to be sure how it works behind the scenes to be sure that when I have the application running with all these users it work fast with standard hardware.
I also require this to use Oracle as a database, but not sure that it is supported and if not, what are the requirements from an Oracle package to enable this facility.
I think that the server is having an active on going non-blocking query on the OPLOG table in mongodb and that is how we get the callback for all the changes in the database. Is that correct ? if so, is there a similar way to do it in Oracle ?
Thanks Roni.
I also require this to use Oracle as a database, but not sure that it is supported and if not, what are the requirements from an Oracle package to enable this facility.
Nope, meteor is currently mongo-only as they have implemented an in-browser library called minimongo. My guess is this project will never support oracle, but who knows. There is no mention of oracle support on the meteor project roadmap
Just happened to come across this question while searching at google.
However, if there are no native solutions. We can always figure out a way for a medium language to issue publishing.
Example Case:
Python will be used for synchronising data between Mongodb and Oracle (24/7 operation using cx_Oracle and MongoDB drivers from python)
Meteor Server will keep watch on what to publish
Meteor clients/browsers that subscribed to the channel that will be updated with oracle data.
I am developing some integration software for a client using amongst other things, C#, NServiceBus and Oracle 10g (client and server). The requirement is that I need to develop a new plugin for NServiceBus to create an implementation of ITransport which is the queuing mechanism for the messages. So Oracle Advanced Queuing is used for this. I have done quite a bit of work writing code for advanced queuing in Oracle 11g (client and server), but looking at ODP.Net 10g it seems that the queuing support is lacking or non-existent so that may prove to be problematic.
My question is this:
I know that you can use the 11g client against a 10g database server, but is it a good idea for Oracle Advanced Queuing and are there any gotchas I need to know about?
Many thanks.
Is it a good idea for Advanced Queueing? Well, I don't see why not, since 11g client connecting to 10g server is supported.
I don't imagine that AQ would pose any unique problem, specific to AQ. If you think about it, AQ is just PL/SQL calls that interact with tables under the covers. There's really nothing different at the client side, than there is with any other Oracle code.
So, I say go for it. But, as always: Test, test test. And then test some more.
But, in principle, I don't see a problem.
You may want to check out the NServiceBus-Contrib project, as there is an AQS transport there for 2.x.
i am looking for an Delphi component to connect to an ORACLE database server in an direct way without install the oracle client.
i knew the Oracle Data Access (ODAC) from DevArt. there are any other component with this capability?
ODAC offers two connection modes to
the Oracle server: connection through
the Oracle Call Interface in Client
mode and direct connection over TCP/IP
in Direct mode. ODAC-based database
applications are easy to deploy, do
not require installation of other data
provider layers.
Thanks in advance.
No, there is no other Delphi Win32 libraries allowing to connect to Oracle without the installed Oracle Client. And, IMHO, that is correct, because:
OCI (Oracle Call Interface) is quite complex piece of software. I will say, it is most complex closed sourced DBMS Call Level Interface in the World. And it is changing from version to version. Oracle has official rule - the Oracle Client v X supports Oracle Server v X-1 ... X+1. Because even such company as Oracle, dont want to spend resources to support and test all the protocol nuances across all possible versions. So, I dont think, that DevArt ever will implement 99.9% stable Oracle SQL*Net protocol implementation. And the INet posts proof that ...
AFAIK, the ODAC Net mode does not support some of the Oracle Client important features and has some important limitations. Although it works well for simple data access scenarious.
If you will purchase Oracle support, then it will decline all your support requests, if they will know, that you are not using official client software. That is just Oracle rule.
If you dislike to install and tune the full scale Oracle Client, then you can just use Oracle Instant Client. Which does not require install or setup procedure. And you will be in safety in case of the different data access scenarious and Oracle Server versions.
PS: Although I may be considered as a biased person :)
There is also Allround Automations Direct Oracle Access, it do require Oracle SQL*Net or Net8. but is a brilliant component suite.
The only solution I found is ODAC, and it's working very nice, I have been using it since years without getting any problem with the direct mode.
there's some limitation with the direct mode, but most of users will not get these limitations with their application.
There are several similar Oracle technologies - Oracle Streams, Oracle Change Data Capture and Database Change Notification.
What are the differences between these?
Are they related to Oracle Advanced Queueing?
Oracle CDC is all about capturing changes in DB tables and the changes are stored in special Oracle tables. There are two modes of CDC operation: asynchronous (based on Java) or synchronous (based on DB triggers, more performance overhead).
Oracle Streams sits on top of Oracle CDC and it's a full transport mechanism (over e.g. HTTP) for data synchronization between 2 servers. It's based on Oracle Advanced Queues technology and it's designed for high performance and reliability.
Both Oracle CDC and Streams are generally used for data synchronization between Oracle DB servers... With Oracle CDC, you don't have to use Oracle Streams for, e.g. you could write your own data export routines which create flat files for the purpose of synchronization between 2 DB servers, whereas with Streams you must have a network link between the 2 servers.
Database Change Notification is something else again, it's not used for server-to-server synch but instead more for server notification of resultset changes to clients, mostly in the context of data caches on the client side.
I would add that for synchronizing between systems, you can achieve asynchronous mode by combining Streams and the CDC publishing mechanism. If you choose not to use Streams for this purpose, you would end up using a synchronous mode (I think it's via triggers) putting a little extra overhead on each transaction.