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Big data is dead (2023)

motherduck.com

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Re: Big data is dead (2023)

#271
post #168
post #32

When I was hiring data scientists for a previous job, my favorite tricky question was "what stack/architecture would you build" with the somewhat detailed requirements of "6 TiB of data" in sight. I was careful not to require overly complicated sums, I simply said it's MAX 6TiB I patiently listened to all the big query hadoop habla-blabla, even asked questions about the financials (hardware/software/license BOM) and…

.parquet files are completely underrated, many people still do not know about the format! .parquet preserves data types (unlike CSV) They are 10x smaller than CSV. So 600GB instead of 6TB. They are 50x faster to read than CSV They are an "open standard" from Apache Foundation Of course, you can't peek inside them as easily as you can a CSV. But, the tradeoffs are worth it! Please promote the use of .parquet files! Ma…

> They are 50x faster to read than CSV

I actually benchmarked this and duckdb CSV reader is faster than parquet reader.

Re: Big data is dead (2023)

#272
post #32

When I was hiring data scientists for a previous job, my favorite tricky question was "what stack/architecture would you build" with the somewhat detailed requirements of "6 TiB of data" in sight. I was careful not to require overly complicated sums, I simply said it's MAX 6TiB I patiently listened to all the big query hadoop habla-blabla, even asked questions about the financials (hardware/software/license BOM) and…

Wait, how would you split 6 TiB across 6 phones, how would you handle the queries? How long will the data live, do you need to handle schema changes, and how? And what is the cost of a machine with 15 or 20 TiB of RAM (you said it fits in memory multiple times, right?) - isn’t the drive cost irrelevant here? How many requests per second did you specify? Isn’t that possibly way more important than data size? Awk on 6 TiB, even in memory, isn’t very fast. You might need some indexing, which suddenly pushes your memory requirement above 6 TiB, no? Do you need migrations or backups or redundancy? Those could increase your data size by multiples. I’d expect a question that specified a small data size to be asking me to estimate the real data size, which could easily be 100 TiB or more.

Re: Big data is dead (2023)

#273
post #32

When I was hiring data scientists for a previous job, my favorite tricky question was "what stack/architecture would you build" with the somewhat detailed requirements of "6 TiB of data" in sight. I was careful not to require overly complicated sums, I simply said it's MAX 6TiB I patiently listened to all the big query hadoop habla-blabla, even asked questions about the financials (hardware/software/license BOM) and…

I can appreciate the vertical scaling solution, but to be honest, this is the wrong solution for almost all use cases - consumers of the data don't want awk, and even if they did, spooling over 6TB for every kinda of query without partitioning or column storage is gonna be slow on a single cpu - always. I've generally liked BigQuery for this type of stuff - the console interface is good enough for ad-hoc stuff, you c…

you can scale vertically with a much better tech than awk.

enter duckdb with columnar vectorized execution and full SQL support. :-)

disclaimer: i work with the author at motherduck and we make a data warehouse powered by duckdb

Re: Big data is dead (2023)

#274
post #32

When I was hiring data scientists for a previous job, my favorite tricky question was "what stack/architecture would you build" with the somewhat detailed requirements of "6 TiB of data" in sight. I was careful not to require overly complicated sums, I simply said it's MAX 6TiB I patiently listened to all the big query hadoop habla-blabla, even asked questions about the financials (hardware/software/license BOM) and…

Plenty of people get offended if you tell them that their data isn’t really “big data”. A few years ago I had a discussion with one of my directors about a system IT had built for us with Hadoop, API gateways, multiple developers and hundreds of thousands of yearly cost. I told him that at our scale (now and any foreseeable future) I could easily run the whole thing on a USB drive attached to his laptop and a few pyt…

In most non-tech companies, it comes down to the motive of the manager and in most cases it is expansion of reporting line and grabbing as much budget as possible. Using "simple" solutions runs counter to this central motivation.

Re: Big data is dead (2023)

#275

Earlier quoted context omitted.

> that people don't try simpler and proven solutions FIRST Well why don't people do that according to you ? Its not 'mind blowing' to me because you can never guess what angle interviewer is coming at you. Especially when they use the words like ' data stack'.

I don't know why and this is why I said it's mind-blowing. Because to me trying stuff that can work on most laptops comes naturally in my head as the first viable solution. As for interviews, sure, they have all sorts of traps. It really depends on the format and the role. Since I already disclaimed that I am not actual data scientist and just a seasoned dev who can make some magic happen without a dedicated data tea…

Thats fair. My comment wasn't directed at you. I was trying to be smart and write an inverse of original comment. Where I as an interviewer was looking for a proper 'data stack' and interviewee responded with a bespoke solution.

"not understanding the scale of "real" big data was a no-go in my eyes when hiring."

Re: Big data is dead (2023)

#276
post #32

When I was hiring data scientists for a previous job, my favorite tricky question was "what stack/architecture would you build" with the somewhat detailed requirements of "6 TiB of data" in sight. I was careful not to require overly complicated sums, I simply said it's MAX 6TiB I patiently listened to all the big query hadoop habla-blabla, even asked questions about the financials (hardware/software/license BOM) and…

I think I've written about it here before, but I imported ≈1 TB of logs into DuckDB (which compressed it to fit in RAM of my laptop) and was done with my analysis before the data science team had even ingested everything into their spark cluster. (On the other hand, I wouldn't really want the average business analyst walking around with all our customer data on their laptops all the time. And by the time you have a p…

you probably didn't do joins for example on your dataset, because DuckDB is OOMing on them if they don't fit memory.

Re: Big data is dead (2023)

#277

Earlier quoted context omitted.

Blows my mind. I am a backend programmer and a semi-decent sysadmin and I would have immediately told you: "make a ZFS or BCacheFS pool with 20-30% redundancy bits and just go wild with CLI programs, I know dozens that work on CSV and XML, what's the problem?". And I am not a specialized data scientist. But with time I am wondering if such a thing even exists... being a good backender / sysadmin and knowing a lot of…

> make a ZFS or BCacheFS pool with 20-30% redundancy bits and just go wild with CLI programs Lol. Data management is about safety, auditablity, access control, knowledge sharing and who bunch of other stuff. I would've immediately shown you the door as someone who i cannot trust data with.

Edit: for above comment.

My comment wasn't directed at parent. I was trying to be smart and write an inverse of original comment. Opposite scenario Where I as an interviewer was looking for a proper 'data stack' and interviewee responded with a bespoke solution.

"not understanding the scale of "real" big data was a no-go in my eyes when hiring."

i was trying to point out that you can never know where the interviewer is coming from. Unless i know interviewer personally i would bias towards playing it safe and go with 'enterpisey stack'

Re: Big data is dead (2023)

#278
post #266
post #209

Earlier quoted context omitted.

FWIW, it's a 2.5 second extra to say "Although you don't need big data, but if you insist, ..." and gimme the hadoop answer.

Sure, but as you said yourself: it's a trick question. How often does the employee have to answer trick questions without having any time to think in the actual job? As an interviewer, why not asking: "how would you do that in a setup that doesn't have much data and doesn't need to scale, and then how would you do it if it had a ton of data and a big need to scale?". There is no trick here, do you feel you lose infor…

Depends on the level you're hiring for. At a certain point, the candidate needs to be able to identify the right tool for the job, including when that tool is not the usual big data tools but a simple script.

Re: Big data is dead (2023)

#279

Earlier quoted context omitted.

I don't know why and this is why I said it's mind-blowing. Because to me trying stuff that can work on most laptops comes naturally in my head as the first viable solution. As for interviews, sure, they have all sorts of traps. It really depends on the format and the role. Since I already disclaimed that I am not actual data scientist and just a seasoned dev who can make some magic happen without a dedicated data tea…

Thats fair. My comment wasn't directed at you. I was trying to be smart and write an inverse of original comment. Where I as an interviewer was looking for a proper 'data stack' and interviewee responded with a bespoke solution. "not understanding the scale of "real" big data was a no-go in my eyes when hiring."

Sure, okay, I get it. My point was more like "Have you tried this obvious thing first that a lot of devs can do for you without too much hassle?". If I were to try for a dedicated data scientist position then I'd have done homework.

Re: Big data is dead (2023)

#280
Big Data hasn't been about storage, I thought it was always about processing. Guy obviously knows his stuff but I got the impression he stressed more about storage and how that's cheap and easy these days. When he does mention processing/computing, he mentions that most of the time people end up only querying recent data (ie small chunk of actual data they hold) but that bears the question: is querying only small chunk of data what businesses need, or are they doing it because querying the whole dataset is just not manageable? In other words, if processing all data at once was as easy as querying the most recent X percent, would most businesses still choose to only query the small chunk? I think there lies the answer whether Big Data (processing) is needed or not.
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