7 ms·

I understand some of the reasons people didn't like Mongo, but this always vexed me. The default write level was very clearly documented and you could always ch

I understand some of the reasons people didn't like Mongo, but this always vexed me. The default write level was very clearly documented and you could always change it as necessary. Surely it would be necessary to read the documentation of a database before rolling it out to production?

justinsb 13y ago
Other databases are forgiving; they are configured "safe", even at the expense of speed. The intention is that you can deploy a small system immediately; if/as you grow you will see that the database is going too slowly. You can _then_ look at the performance/safety dials you can tune and choose appropriate trade-offs. These are systems designed for the real world, where people don't read the manual until they have to. When people assume MongoDB was similarly designed with their best interests in mind, that's when things go wrong.
- functional_test 13y ago
  I'm not sure how anyone else could know what my best interests are. There are a lot of real world applications where small amounts of data loss don't matter but latency matters a lot. Any time I deploy something as critical as a database, I carefully read about what it does and how it works. Not doing so is like signing a contract without reading it.
  - justinsb 13y ago
    MongoDB is optimized for Mongo Inc, not for you, not for me.
  - gbog 13y ago
    > a lot of real world applications where small amounts of data loss don't matter but latency matters a lot. I don't understand this reasoning. We are talking about defaults. Defaults are used by people who did not tweak the settings yet. If I am just starting building a thing, I will have bugs and squeaks and I want to make sure I am not fooled by some unreliable data store. I am not likely to need 100GiB/s throughput, but I am very likely to have to hunt bugs, like "I did click on this <like> button but it did not add to the total likes". And I would really really hate it if after half a day of bug hunting I would realize that my data store just didn't store the thing...
- icelancer 13y ago
  >When people assume MongoDB was similarly designed with their best interests in mind, that's when things go wrong. No, I just assume that a database has a similar set of features as other databases have had for decades. Mongo does not; it is clearly the exception - and for possibly nefarious reasons, as well.
rdtsc 13y ago
> Surely it would be necessary to read the documentation of a database before rolling it out to production? You buy a car. It comes with brakes disabled because for whatever reasons that also lets it get to a higher top speed. You are expected to read you car owner manual and on page 54 you find that you have to hold "enable brakes" button under the console for 10 seconds to turn on your brakes. Would it vex you that people might be slightly critical of that car. Clearly they are silly for not reading their car manual until page 54. That "feature" is not something that should be discovered by reading docs or when you get a crash and then load a backup from another week and still get a crash and then you start hitting your head on your desk. Anything calling itself a "database" should not have shipped with those default settings _ever_. If they did they might have gotten away with it in my book by having a big flashing red warning on the front or download page. I don't remember one.
- Stealth- 13y ago
  I believe the write concern default is under the responsibilities of the driver -- not the Mongo Daemon.
- functional_test 13y ago
  I would also read the manual of a car I just bought before driving it. I guess that's just my style. Don't get me wrong, I'm not saying your assumption is unreasonable. But in the end, it's on you as a conscientious developer to read the documentation. I'm not even suggesting cover to cover - in this case though they are very up front about write concerns. There is no real excuse to find this out any other way, it's just negligence.
  - clwk 13y ago
    Out of curiosity, have you ever bought a car, and did you actually read the whole manual before driving it? It's a nice hypothetical, and that might be your style. Most real-world car purchase scenarios I'm familiar with would make that style impractical.
    - functional_test 13y ago
taspeotis 13y ago
> I understand some of the reasons people didn't like Mongo, but this always vexed me. The default write level ... Surely it would be necessary to read the documentation I don't have much sympathy for people who can't RTFM but storing data is kind of a thing for databases.
- dijit 13y ago
  the word "Database" brings forth images of ACID compliance. if you're not trying for that standard at all, it's false advertising.

justinsb 13y ago

Other databases are forgiving; they are configured "safe", even at the expense of speed. The intention is that you can deploy a small system immediately; if/as you grow you will see that the database is going too slowly. You can _then_ look at the performance/safety dials you can tune and choose appropriate trade-offs. These are systems designed for the real world, where people don't read the manual until they have to. When people assume MongoDB was similarly designed with their best interests in mind, that's when things go wrong.

functional_test 13y ago
I'm not sure how anyone else could know what my best interests are. There are a lot of real world applications where small amounts of data loss don't matter but latency matters a lot. Any time I deploy something as critical as a database, I carefully read about what it does and how it works. Not doing so is like signing a contract without reading it.
- justinsb 13y ago
  MongoDB is optimized for Mongo Inc, not for you, not for me.
- gbog 13y ago
  > a lot of real world applications where small amounts of data loss don't matter but latency matters a lot. I don't understand this reasoning. We are talking about defaults. Defaults are used by people who did not tweak the settings yet. If I am just starting building a thing, I will have bugs and squeaks and I want to make sure I am not fooled by some unreliable data store. I am not likely to need 100GiB/s throughput, but I am very likely to have to hunt bugs, like "I did click on this <like> button but it did not add to the total likes". And I would really really hate it if after half a day of bug hunting I would realize that my data store just didn't store the thing...
icelancer 13y ago
>When people assume MongoDB was similarly designed with their best interests in mind, that's when things go wrong. No, I just assume that a database has a similar set of features as other databases have had for decades. Mongo does not; it is clearly the exception - and for possibly nefarious reasons, as well.

rdtsc 13y ago

> Surely it would be necessary to read the documentation of a database before rolling it out to production? You buy a car. It comes with brakes disabled because for whatever reasons that also lets it get to a higher top speed. You are expected to read you car owner manual and on page 54 you find that you have to hold "enable brakes" button under the console for 10 seconds to turn on your brakes. Would it vex you that people might be slightly critical of that car. Clearly they are silly for not reading their car manual until page 54. That "feature" is not something that should be discovered by reading docs or when you get a crash and then load a backup from another week and still get a crash and then you start hitting your head on your desk. Anything calling itself a "database" should not have shipped with those default settings _ever_. If they did they might have gotten away with it in my book by having a big flashing red warning on the front or download page. I don't remember one.

Stealth- 13y ago
I believe the write concern default is under the responsibilities of the driver -- not the Mongo Daemon.
functional_test 13y ago
I would also read the manual of a car I just bought before driving it. I guess that's just my style. Don't get me wrong, I'm not saying your assumption is unreasonable. But in the end, it's on you as a conscientious developer to read the documentation. I'm not even suggesting cover to cover - in this case though they are very up front about write concerns. There is no real excuse to find this out any other way, it's just negligence.
- clwk 13y ago
  Out of curiosity, have you ever bought a car, and did you actually read the whole manual before driving it? It's a nice hypothetical, and that might be your style. Most real-world car purchase scenarios I'm familiar with would make that style impractical.
  - functional_test 13y ago

taspeotis 13y ago

> I understand some of the reasons people didn't like Mongo, but this always vexed me. The default write level ... Surely it would be necessary to read the documentation I don't have much sympathy for people who can't RTFM but storing data is kind of a thing for databases.

dijit 13y ago
the word "Database" brings forth images of ACID compliance. if you're not trying for that standard at all, it's false advertising.