ClickHouse vs. Db2

The most important thing when using ClickHouse is to be clear that the scenarios in which you want to use it really are the right ones. Many users think that when a database is very fast for a specific use case, it can be extrapolated to other contexts (most of the time different) in which a previous analysis has not been carried out.

ClickHouse is an analytical database, as such, it should be used for such purposes, where the information is stored correctly, the data volumes are really large and the queries to be performed are not the typical traditional queries on several columns with multiple aggregations. ClickHouse is not the solution for this.

On the other hand, if your case is not one of the above, it is quite possible that ClickHouse can help you. Where ClickHouse shines is when you are looking for aggregation over a particular column in large volumes of data.

Incentivized

I could think of a couple but the obvious is in Fintech and Retail, because of the amount of transactional and event level data for global operations. It is imperative to have a solution that can handle such large scale date, in real-time and batch delivery for inbound and outbound delivery, and ultimately ensuring that workload management is supported in some cases for around the clock SLAs.

Incentivized

• Opensource
• High performance
• Multiple engines to adapt user cases
• Easy configuration of data replication

Incentivized

• DB2 maintains itself very well. The Task Scheduler component of DB2 allows for statistics gathering and reorganization of indexes and tables without user interaction or without specific knowledge of cron or Windows Task Scheduler / Scheduled jobs.
• Its use of ASYNC, NEARSYNC, and SYNC HADR (High Availability Disaster Recovery ) models gives you a range of options for maintaining a very high uptime ratio. Failover from PRIMARY to SECONDARY becomes very easy with just a single command or windowed mouse click.
• Task Scheduler ( DB2 9.7 and earlier ) allows for jobs to be run within other jobs, and exit and error codes can define what other jobs are run. This allows for ease of maintenance without third party softwares.
• Tablespace usage and automatic storage help keep your data segmented while at rest, making partitioning easier.
• Ability to run commands via CLI (Command Line Interface) or via Control Center / Data Studio ( DB2 10.x+) makes administration a breeze.

Incentivized

• Avro data manipulation
• Kafka consistency
• DDL operations errors (by replica configuration)

Incentivized

• The relational model requires a rigid schema that does not necessarily fit with some types of modern development.
• Proprietary database, requires a lot of Hardware for its good performance and its costs are high.
• As data grows in production environment, it becomes slow.

Incentivized

The DB2 database is a solid option for our school. We have been on this journey now for 3-4 years so we are still adapting to what it can do. We will renew our use of DB2 because we don’t see. Major need to change. Also, changing a main database in a school environment is a major project, so we’ll avoid that if possible.

Incentivized

You have to be well versed in using the technology, not only from a GUI interface but from a command line interface to successfully use this software to its fullest.

Incentivized

I have never had DB2 go down unexpectedly. It just works solidly every day. When I look at the logs, sometimes DB2 has figured out there was a need to build an index. Instead of waiting for me to do it, the database automatically created the index for me. At my current company, we have had zero issues for the past 8 years. We have upgrade the server 3 times and upgraded the OS each time and the only thing we saw was that DB2 got better and faster. It is simply amazing.

Incentivized

The performances are exceptional if you take care to maintain the database. It is a very powerful tool and at the same time very easy to use. In our installation, we expect a DB machine on the mainframe with access to the database through ODBC connectors directly from branch servers, with fabulous end users experience.

Incentivized

Easily the best product support team. :) Whenever we have questions, they have answered those in a timely manner and we like how they go above and beyond to help.

Incentivized

the material was very clear and all subjects have been handled

Incentivized

db2 work well with the application, also the replication tool can keep it up

ClickHouse was not compared to them as a competitor but as the ideal partner to complete an information analysis system, providing users with the most complete and efficient tools. Therefore, in this case it was considered that it would be the ideal candidate due to its characteristics compared to the other competitors.

Incentivized

DB2 was more scalable and easily configurable than other products we evaluated and short listed in terms of functionality and pricing. IBM also had a good demo on premise and provided us a sandbox experience to test out and play with the product and DB2 at that time came out better than other similar products.

Incentivized

By
using DB2 only to support my IzPCA activities, my knowledge here
is somewhat limited.

Anyway,
from what I was able to understand, DB2 is extremely scallable.

Maybe the information below could serve as an example of scalability.

Customer have an huge mainframe environment, 13x z15 CECs, around
80 LPARs, and maybe more than 50 Sysplexes (I am not totally sure about this
last figure...)

Today
we have 7 IzPCA
databases, each one in a distinct Syplex.

Plans
are underway to have, at the end, an small LPAR, with only one DB2 sub-system,
and with only one database, then transmit the data from a lot of other LPARs,
and then process all the data in this only one database.

The
IzPCA collect process (read the data received, manipulate it, and insert rows
in the tables) today is a huge process, demanding many elapsed
hours, and lots of CPU.

Almost
100% of the tables are PBR type, insert jobs run in parallel, but in 4 of the 7
database, it is a really a huge and long process.

Combining
the INSERTs loads from the 7 databases in only one will be impossible.......,,,,

But,
IzPCA recently introduced a new feature, called "Continuous
Collector".

By
using that feature, small amounts of data will be transmited to the central
LPAR at every 5 minutes (or even less), processed immediately,in
a short period of time, and with small use of CPU,
instead of one or two transmissions by day, of very large amounts of data and
the corresponding collect jobs occurring only once or twice a day, with long
elapsed times, and huge comsumption of CPU

I
suspect the total CPU seconds consumed will be more or less the same in
both cases, but in the new method it will occur in small bursts
many times a day!!

Incentivized

• Queries that used to take more than 2 minutes now take less than 1 second
• Possibility to analyze use cases in real time (before was impossible)
• The applications are more complete and the users decisions are better

Incentivized

• Fast response time by processing optimization and cost reduction by reduced CPU utilization. Nowadays, good performance is a necessary condition for the survival of a company and its sustained growth
• SQL enhancements are targeted to improve performance, simplify current and new applications, and reduce the development cycle time to market.
• A CPU reduction at peak times can immediately reduce our TCO by reducing software costs related to CPU utilization.
• Impressive reductions in memory requirements, which used to limit the concurrent database activity
• Out-of-the-box savings without changing the database or application

Incentivized