Is it possible to organize asynchronous data exchange with separate files (transportable tablespaces maybe) using Oracle Streams? I.e, is it possible to organize offline replication using files?
You may want to consider using DataPump or imp/exp if you want to do this in batches with files. You would use these tools to export the things you want, then get the files over to the other database and import them.
If you have a poor connection between the two hosts, however, you're going to run in to the same problem you're running in to with your snapshots and database links. You still need to get the data across to the other box.
Oracle Streams is another option that may be able to basically queue up transactions while the link is unusable, but is a far more advanced topic and one you may want to consider hiring a consultant for.
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We're considering Snowflake and want to understand how we could use it, and possibly other tools, to overcome one of our main problems - ETL! We currently use a legacy DWH with an ETL process consisting of SSIS and some views. This has all the common pitfalls of this methodology - most notably that it takes ages!
I was under the assumption that we'd move to an ELT model in Snowflake, I started to research tools to do the 'T' part of it, however, I'm just listening to this podcast: https://www.dataengineeringpodcast.com/snowflakedb-cloud-data-warehouse-episode-110/
And it's suggesting that just slapping a SQL View over something and exposing it in say PowerBI or Tableau is enough for the T part of things!...
Just wondering what people's experience was here?
- Do you do transformations just by writing a view in Snowflake?
- Do you use a third party tool specifically to address this need?
Secondary to this, for the Extraction and Loading, do you:
- Do this using Snowflake only
- Use a third party tool
I'm specifically interested if you do this to create some kind of timeseries in Snowflake from a non timeseries source. That's something we'd be keen to do.
This question is hard to answer without sounding opinionated, especially not knowing your use case. For what it's worth here is what I think:
Don't stick views on top of your tables and expose to a reporting tool unless you have a very very simple setup. If you're considering a tool like Snowflake then you will probably want to go for something more sustainable, this approach can become prohibitive in terms of cost and complexity in your views.
Use a third-party tool to manage your ELT process. Your choice of tool will depend on your internal skills and cloud strategy, have a look at the tools out there like Stich, Fivetran etc. If you don't mind having on-premise technologies why not stick with SSIS or use something like Apache Airflow (requires up-skilling)
Snowflake will not help you with the E of ELT, you will need to use a third-party tool to manage the extract of data from your other systems like SSIS. It will help with the L part, for this you can use Snowpipe or COPY commands which are available within the Snowflake ecosystem. Snowflake will also help you share your data with external parties which is really nice.
My organization has created a fairly complicated dimensional model in Snowflake using layers of SQL views, against which we can point our reporting tools. We use a separate replication tool for extraction from source systems and loading into Snowflake. Using views simplifies our approach in that we don't need to use an additional tool. It also makes managing the code easier than something like SSIS. For instance, we can search for code using the Snowflake interface or our version control tool instead of having to open individual SSIS packages.
Given a pre-production oracle database and a production oracle database and if around 300K records need to be transferred from the former to the latter, would using a messaging system such as an ESB/JMS/TIBCO be a good option?
I don't know Oracle, but if I was trying to asynchronously replicate data with SQL Server, I would use their own internal tools to accomplish it. I would imagine Oracle has similar tools to run jobs to copy between two Oracle databases.
However, I do have quite a bit of experience using an ESB (Mule) with ActiveMQ to replicate data across database technologies. Specifically I've done SQL Server->Mongo and MySQL->Mongo with Mule and ActiveMQ.
So far I've found Mule to be a wonderful solution - especially coupled with ActiveMQ. I've been able to replicate about 400k Wordpress blog posts (from MySQL) to Mongo in about 20 minutes. To transfer 100k articles from a CMS system we were able to get it done in about 30 minutes.
I figured I'd weigh in because you mentioned and ESB and messaging. I would go that route if the integration points are heterogenous. If you do go down that route, Mule is awesome.
If you are trying to move data from an old database to a new one instead of doing it asynchronously, possibly a simpler method would be sql injection. Assuming your old database allows you to "export" your database, when you export it you will download a sql file. Then you can just open that sql file in a program like notepad and copy-paste that code in the sql executor at your new database and it will re-create all your tables and populate them with the old data.
Actually using the database tools will be the recommended method for replicating data between databases.
When using messaging, one does not get the guarantee that the data will be transferred in the same sequence as it was sent and honor relationships between tables, potentially resulting in replication errors, unless one builds up some mechanism on the JMS receiver side to maintain the sequence. But that looks rather like an overhead.
I'm writing a report and thought you guys could help by providing me with the costs of company support in setting up and training a client on a data integrator for Salesforce. E.g., if someone wants to use Salesforce, but first needs a tool to consolidate and transfer data from back office systems to Salesforce how much would that support service cost?
Salesforce actually comes with a very good integration tool called Data Loader. It can be run as an interactive application under Windows or Macintosh, or it can be run as a command-line tool on Windows, Mac or Linux.
In interactive mode, it can import & export CSV files.
In batch mode it can also read data from, and write data to, a database.
For example, I have a Linux server where a daily cron job activates the Data Loader which runs several jobs. Some of these jobs run SQL against a database and upload the resulting data into Salesforce. Other jobs extract from Salesforce (using their SOQL query language, which is SQL-like) and store the information into a database.
Data Loader has a bit of a learning curve for batch mode (mostly around creating some XML configuration files), but the Interactive mode is very easy to use.
So, to answer your question... If it's a one-time data load, just run the interactive version and it's easy. If you want regularly-updated data, then use the batch mode. Support costs for operating the integration are really all in the setup. Once it's running, there shouldn't be any on-going costs unless the data structures change and you want to change the data being transferred. Better yet, if the system is setup by somebody who has done it before, you'll avoid a big learning curve.
If you want a figure to put into your report, then allow 3 days for the initial integration (allows for learning curve) and then a half-day for each additional one. That's generous, but provides extra time to debug problems.
To some degree, it depends on two factors:
Where is the data's source of truth?
How often do you want to sync the data?
If the answers are "it's a weird place and I only need to sync it once," then you probably want to figure out how to get it in CSV form and then use tools built into Salesforce to import it.
However, if the data lives in a database or data warehouse (postgres, mysql, mongo, redshift, snowflake, big query, etc) and especially if you want to keep Salesforce up to date with that source of truth continuously, then you could look into so-called "Reverse ETL" tools made for this purpose.
Costs depend on the tool chosen and the data volumes and other factors, but here are some options:
Grouparoo is an open source Reverse ETL tool. You can host it yourself for free. Paid plans start at $150/month.
Census is a SaaS Reverse ETL tool. Paid plans start at $300/month.
Hightouch is a SaaS Reverse ETL tool. Paid plans start at $350/month.
I have an ASP .NET application that connects to an Oracle or a SQL Server database. An installer has been developed to install a fresh database to an existing SQL Server using sql commands such as "restore database..." which simply restores a ".bak" file which we keep under source control.
I'm very new to Oracle and our application has only recently been ported to be compatible with 10g.
We are currently using the "exp.exe" tool to generate a ".dmp" file and then using the "imp.exe" to import it into a developers box.
How would you go about creating an "Oracle Database Installer"?
Would you create the database using script files and then populate the database with required default data?
Would you run the "imp.exe" tool behind the scenes?
Do we need to provide a clean interface for system administrators so that they can just select the destination server and have done, or should we just provide them with the ".dmp" file? What are the best practices?
Thanks.
The question is -- what do your customers know about Oracle?
Nothing? You should probably rethink this position. Oracle is very large and complex. If you assume your customers know nothing, you'll then start providing tutorials and help that's inappropriate.
Minimally Competent? If they're competent, they know enough to run imp by themselves. Also, they know enough to run a script that executes SQL.
Actual DBA's? Most organizations that can afford Oracle can afford real DBA's. Real DBA's can cope with a lot of things -- they do not need much hand-holding. Some of them like to assign storage parameters according to their shop standards.
You should provide a script with reasonable defaults. You should define your script in a way that someone can easily find all of your storage parameters and tweak them if necessary.
Your initial data can be via export/import or via a script. I prefer a script.
I have done this repeatedly from both sides (consumer and provider) as a DBA, developer, and architect.
As a provider, one of my grand accomplishments (in 1996) was the creation of an installation CD for a commercial insurance claims management software product targeted to the largest insurance carriers (a multi-million dollar item). That installation CD installed the Oracle 7.2 RDBMS engine, the FileNet optical storage system (scans paper documents and creates cataloged binary versions), and our custom claim-processing application (built in VB 4.0), all integrated and ready to run. As part of the installation process, the user could skip the Oracle software installation or customize it, and the user could customize/override the database configuration in all of its major details (database, schemas, tablespaces, sizes, disks, etc.).
I also provided the field service for this product, which included traveling to the client site as necessary. I tested the installation CD literally hundreds of times under every imaginable scenario that I could replicate, and we NEVER had a field failure that required even a phone call, let alone a trip (I did travel on four occasions, but for pre-sales stuff instead).
More recently (2007), I scripted the creation of an Oracle 10g database for an internal system at a megacorp. In production, the database was sized at 8 TB, mostly for a single transaction table with high data volume. In test, the database was sized around 1 TB for a modest server. In development, the database was sized around 100 MB to run on my laptop. The EXACT SAME SCRIPTS created all three environments, and I could extend them to handle a new environment/machine in about five minutes. This database involved extreme performance tuning, so customization of all pertinent characteristics was absolutely crucial.
Back to the insurance claims processing product--let me please add that I was originally hired to lead its conversion from a SQL Server database to an Oracle database. That conversion was identified as a business necessity because most potential clients did not view a SQL-Server-based product as a professional, serious solution. That is not quite as common today, but it still applies in general: a software product has a better chance of market penetration if it can accommodate multiple database options as preferred by the target customers (especially enterprise-class customers).
Likewise, the installation CD was also viewed as an essential element. However, that situation and many more have revealed to me that most "real" DBAs will not accept an import-based database installation. As a DBA and architect, I know that I definitely will not for the same reasons.
Simply put, an import-based database installation gives the customer almost no control over the resulting database. It is opaque to the customer, leaving them questioning what it did. It forces the customer to expend massive efforts to attempt to exercise what little control they can. It is notoriously fragile and error-prone (Oracle imports are well known for ownership and permission problems, constraint problems, etc.). Weighing all those impacts, an import-based database installation is unprofessional--it does not put the customers' needs first.
Scripting the database installation provides the right kind of transparency, configurability, selective repeatability, and overall customer control that professionalism demands. It also encourages you to properly understand the impacts of your database design decisions in a way that an import does not.
Best wishes.
Personally I favour SQL scripts to database creation and data loads where possible. I tend to use PL/SQL Developer. It has some good options to generate scripts from an existing database. Once you have these you can run the scripts using sqlplus or any application code that can execute arbitrary SQL (eg JDBC with Java). Toad is the more common (and more expensive) tool for Oracle development.
The only limitation of a SQL export is it can't export CLOB/BLOB fields. If you have those, you either need to do them separately (as a PL/SQL export) or do the whole thing as a PL/SQL export. Theres no dramas with this except the file is effectively a binary export (extension .pde) and is more limited in how you can execute it.
The other big advantage of SQL source files is they can be version controlled easily. It's really handy to be able to create a database environment by running one or two scripts.
The import and export tools for Oracle I think are more applicable for backup and restore operations.
Now, as for delivering that to a customer, from your comments it seems that you'll be giving this to DBAs. Pretty much any Oracle installation will have DBAs involved. They will be fine with SQL scripts to create the schema and do the data load. They will be doing a lot of site-specific configuration (eg tuning the SGA, temp tablespaces, # of concurrent connections, etc based on expected load).
You, as the vendor, can give guidance on any relevant configuration and you may get involved in support and possibly installation but ultimately it's up to them to figure out what works for them. Oracle runs on a large number of operating systems and hardware variants with infinite variations in network topology and firewall configuraiton. You can't factor in all of these to an installer or even a set of instructions (other than the guidelines mentioned previously).
The last time I was involved in the creation of a (oracle) db (for a reasonably large company with in-house DBAs) the DBAs wanted to know things like:
what we wanted to call the db,
what tablespaces we would need, and an estimate of how much data would be in each one
how many users would be connecting.
(From memory) they set up the db and tablespaces, then we provided a combination of simple scripts that they could run (or clear instructions if a task wasn't easy to automate)
As I say this was for an in-house app, so your mileage may vary, but in my case they wanted all instructions clearly spelt out so that (a) there was no possibily of a misunderstanding leading to the wrong thing being done, and (b) no culpability on their part if something didn't work ("we were just following the instructions")
What's the best way to maintain a multiple databases across several platforms (Windows, Linux, Mac OS X and Solaris) and keep them in sync with one another? I've tried several different programs and nothing seems to work!
I think you should ask yourself why you have to go through the hassle of maintaining multiple databases across several platforms and have them in sync with one another. Sounds like there's a lot of redundancy there. Why not just have one instance of that database, since I'm sure it can be made accessible (e.g. via SOA approach) to multiple apps on multiple platforms anyway?
Why go through the hassle? Management claims it's more expensive?
Here's how to prove them wrong.
Pick one database, call it the "master" or "system of record".
Write scripts to export data from the master and load it into your copies. If you have a nice database (MySQL, SQL/Server, Oracle or DB2) there are nice tools to do this replication for you. If you have a mixture of databases, you'll have to resort to exporting changed data and reloading changed data. The idea is that this is a 1-way copy: master to replicants.
Fix each application, one at a time, to do updates in the master database only. Since each application has a JDBC (or ODBC or whatever) connection to a database, it can just as easily be a connection to the master database.
Once you've fixed the applications to update only the master, the replicas are worthless. Management can insist that it's cheaper to have them. And there they are -- clones of the master database -- just what management says you must have.
Your life is simpler because the apps are only updating the system of record. They're happy because you have all the cloned databases lying around.