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Top 5 Reasons People Dismiss PostgreSQL

Jane Walker writes "In an effort to dispel some of the FUD surrounding this impressive product, this article puts forth several of the most commonplace reasons for a user to dismiss PostgreSQL." From the article: "While PostgreSQL's adoption rate continues to accelerate, some folks wonder why that rate isn't even steeper given its impressive array of features. One can speculate that many of the reasons for not considering its adoption tend to be based on either outdated or misinformed sources."

19 of 704 comments (clear)

  1. Availability by Anonymous Coward · · Score: 5, Insightful

    MySQL is pre-installed by most webhosts, and does the job for most tasks.

    First post?

    1. Re:Availability by NutscrapeSucks · · Score: 5, Insightful

      I know MS Access, Access came with Office, Access is fast and easy, and Access does all the things that I need a database to do...

      (Only partially being sarcastic here. Access is fine for a lot of things. It's just the mentality that kills me. LAMP Developers are the true heir to the VB/Access Guy Mentality)

      --
      Whenever I hear the word 'Innovation', I reach for my pistol.
  2. Other things... by Saeed+al-Sahaf · · Score: 5, Insightful

    Indeed. And once most people are familure with MySQL and the various tools and language support, there tends to be little reason to switch. PostgreSQL is a better database product, but many (all?) of the features that it's cheering section continue to tell us all about whenever the issue comes up, are simply not ones that the majority of MySQL users want or need. Maybe PostgreSQL fans should target Oracle usres.

    --
    "Who are in control, they are not in control of anything - they don't even control themselves!" - Glen Beck
    1. Re:Other things... by jadavis · · Score: 5, Insightful

      What about consistency? I talk to people all the time who are befuddled by MySQL's lax type checking. I know it's been hashed out before on /., but February 31st is NOT a date, and does not belong in any column named "date".

      If your application has an bug and inserts an invalid date, you don't want that error to cascade to another application (or another part in your application) and cause more errors down the line. By the time you detect the bug, it could be almost impossible to determine the source of the bug.

      Putting consistency checking in application A doesn't prevent application B from inserting invalid data. And when application A reports an error (due to it's wonderful in-application consistency checking), now you don't know what caused the error. It's long past the time that you can get meaningful state information from application B, at most you have database auditing tools that tell you "application B did it", but that's more easily implemented in PostgreSQL as well (triggers).

      And I'm not talking about super-advanced users only. I am talking about everyone who wants to catch the error early when they have the most possible information. Everyone who's just a programmer who wants to be able to trust that data from the database comes in a meaningful form. Everyone that just wants the database to do either what they expect, or throw an error.

      --
      Social scientists are inspired by theories; scientists are humbled by facts.
    2. Re:Other things... by jbolden · · Score: 4, Insightful

      I agree with you 100% (and I'm an Oracle guy). Where I think the free databases are:

      Postgres -- getting closer to the kinds of features Oracle users want. Probably about at 8i level now. OTOH speed is nowhere near Oracle

      MySQL -- Roughly the same speed as Oracle. Doesn't scale. Features ain't even close (though 5 is miles ahead of 3, another 10 years and...)

      The problem for Oracle corporation is that 95% of Oracle users don't need the features of Oracle and thus MySQL is a good replacement for them.

    3. Re:Other things... by adolfojp · · Score: 4, Insightful

      I "inherited" a badly designed MySQL database that a couple of developers were shoveling data into with their nifty little apps. Empty dates were sometimes NULL and sometimes 0000-00-00 and sometimes something else. Also, since it was designed with MyISAM tables there was no referential integrity and there were countless orphans. I am so glad that it was not a database that dealt with bank accounts.

      MySQL has never cared about enforcing database integrity and are just starting to do so. The sad part is that the vast mayority of the people that use MySQL because it is the default database don't fully understand what data integrity or consistency is.

      Cheers,
      Adolfo

    4. Re:Other things... by jadavis · · Score: 4, Insightful

      I would be interested to see some benchmarks to back that up. PostgreSQL has a lot of features that can be used to improve the speed of a query by orders of magnitude.

      What if you have a table and you need a functional index on a user defined function? MySQL can't even do that, so it will be forced to scan the whole table. PostgreSQL makes it trivial.

      PostgreSQL can also combine indexes into in-memory bitmaps before looking in the table. That means you don't have to make a multi-column index for every combination of attributes you select. This is done automatically by the planner.

      When you actually make use of some of the "features that nobody needs" in PostgreSQL, you can see huge performance gains. I'm not sure how it stacks up against Oracle, because they don't let their users publish results.

      But yeah, you're right. If you just port some MySQL code to PostgreSQL, the PostgreSQL code will likely not perform as well (unless there are joins where the planner can use some of the features like the bitmap index).

      --
      Social scientists are inspired by theories; scientists are humbled by facts.
    5. Re:Other things... by jadavis · · Score: 5, Insightful

      Excellent point. That breaks isolation, and a bug in one application can still cascade problems into other applications.

      In particular this is likely to allow security problems in the application to cause malformed data to be entered into the database, thereby affecting other applications.

      --
      Social scientists are inspired by theories; scientists are humbled by facts.
  3. Number 1 (missing) reason by malraid · · Score: 4, Insightful

    Their database (MySQL, Access, Oracle, whatever) is working for them good enough to justify switching. Me? I'm using PostgreSQL, and I won't switch, even though Oracle now has a free version. Too much work to fix something that's not broken. And while I might never be able to use MySQL in my main project because it lacks some features I really need, it's good enough for lots of people.

    --
    please excuse my apathy
  4. #1 Reason by __aanonl8035 · · Score: 5, Insightful

    It has to do with mindshare and previous history. Way back in the day... 1997, postgres was difficult to setup for some people. It was not the default choice included in many setups at ISPs. If you wanted to have an interactive web application at an ISP, on a unix machine, the most common option was MySQL. (On a windows machine it would be an ODBC connection to an access database, or a MS SQL server) Once something has achieved a significant mindshare and some momentum it is difficult to overcome. (But not impossible, especially if you do a better job, just takes time)

  5. Fulltext Indexes by inio · · Score: 4, Insightful

    I have pretty simple requirements for a database, I don't need triggers, stored procedures, or any of that stuff. What I need for web applications is a database that I can efficiently search, and that means fulltext indexes. Sure, there's plugins for Postgres that add fulltext indexes, but they require ungodly complex setup and tuning. With MySQL it's two keywords.

  6. Re:Web developers... by syphax · · Score: 4, Insightful


    I think what the grandparent meant is that a database can do more than handle SELECT, UPDATE, and INSERT queries, and that web apps that use DB backends contain a lot of code for functionality that could have been handled more efficiently and cleanly by the DB itself.

    Ironically, I think your post kind of validates the grandparent, in that you seem to implicitly be thinking of SQL databases as little more than a better place to store data than a flat file.

    Cheers.

    --
    Simple Unexpected Concrete Credible Emotional Stories
  7. Re:Or this? by rtaylor · · Score: 5, Insightful

    Do you really only have one user using the database at any given time? If you do only have one user, speed probably doesn't matter at all.

    Benchmarks like that should be run with a couple of hundred active users all doing different things (mix of updates, insert, deletes, and selects) -- a real world use-case.

    You will quickly find that scores change.

    We had a MySQL versus PostgreSQL battle once. The MySQL people put together a benchmark showing MySQL was nearly 10 times faster. The benchmark was a single user going through the steps.

    We then took the exact same thing and put Apache in front and benchmarked with 5 active users -- now they were about even. At 10 users PostgreSQL was about 5x faster. At 100 users MySQL was unable to finish the test. PostgreSQL was serving each of the 100 users at a rate comparable to how it dealt with 10 active users.

    Benchmarks for benchmark sake is useless. Benchmarks that model your actual use case are quite valuable.

    --
    Rod Taylor
  8. Why I chose MySQL by Reality+Master+101 · · Score: 4, Insightful
    First, let me say that one of my "real" sites uses PostgreSQL, has used it for about six years, and I'm very happy with it. It was the right decision.

    Now, about a year ago, I had a client that wanted a web site back-end written. Now, I wasn't sure what the future of that site was going to be, whether I was going to be involved, etc. I also knew that it would be probably be run on inexpensive shared hosting solutions.

    Guess what I chose? MySQL and PHP. The reason was because those are always available. It gives my client the flexibility to move it to any hosting solution. PostgreSQL simply is not everywhere. In my case, I run my own servers and can afford to have to understand it. But my client needs a hosting solution that does all the work for him (including back-ups). There's something to be said for using "the standard".

    And you know what? I originally chose PostgreSQL because it was ACID compliant, but I have to say that MySQL sucks a lot less than it used to. It defaults to tables that support commit/rollback. It supports sub-transactions (which PostgreSQL v7 doesn't support, not sure about 8). It (FINALLY) supports sub-selects. If you're still turning up your nose at MySQL, it really isn't as bad as it used to be.

    --
    Sometimes it's best to just let stupid people be stupid.
  9. Reason number 6 by porkThreeWays · · Score: 4, Insightful

    Reason number 6 is the damnned Postgres zealots that feel the need to bash everyone else's database rather than promote their own. I use MySQL and Postgres on a regular basis. I'm proficient in both. And to the dismay of Postgres users everywhere, there are times which *gasp* MySQL is better suited. "Oh, you are probably a lame programmer and use it for trivial web stuff". Not true! I look at a project and each databases strenths. It has nothing to do with the seriousness of an application. When I was writing VoIP billing software, we'd sometimes see 4-5 million CDR's (call detail records) in a single day. Our first iteration actually used Postgres and choked on that many records. We had to make some compromises with MySQL. We had an additional field for Unix epoch time because of MySQL's lacking (at the time) date and time math. There was a tradeoff. It was deemed that having billing invoices generate in 5 seconds (as opposed to 5 minutes) was more important than programmer time. Welcome to the real world. Another project I had was for writing worker punchcard system. Six months of records only topped out at 50,000 records and we decided Postgres' procedural languages would be a great help to us. Lose the zealots and attitude and maybe you'll have a greater user base.

    --
    If an officer ever threatens to taze you, say you have a pacemaker.
  10. A few more reasons by jdoeii · · Score: 4, Insightful
    VACUUM is a pain. It's true that VACUUM is annoying, but later releases (especially 8.0 and 8.1) make VACUUM much more tolerable;

    Vacuum kills performance. Some uses maybe OK with loosing 50% or more while VACUUM runs. In some uses it's unacceptable. In our case (a lot of inserts with majority of selects going for the newly inserted records) performance degrades within 6-8 hours after running VACUUM & friends. VACUUM takes ~20 minutes to complete which is completely unacceptable during the day and we can't delay it till night.

    No, AUTOVACUUM is not an answer because it kicks in unexpectedly and makes random queries run unexpectedly slow at unexpected times. Usual VACUUM makes all queries run slow at predetermined time. Not a very appealing choice.

    More reasons:
    • No memory management. For example, here is 1GB database on a dedicated host with 2GB of RAM. PG should suck the while DB into RAM and run selects from there, right? Wrong. PG is extremely frugal about memory management. It caches the last few results, but otherwise goes to disk for data even if there is anough RAM to cache the whole DB. The PG developers keep saying that it's the job for the OS. Now, which OS should we use then? FreeBSD, Linux, Windows? Which one?
    • Forever broken COUNT(). Although MIN & MAX were fixed in the latest release, COUNT() is still broken and there is no fixing in sight. Yes, I beieve 10 seconds execution time for count() on a table with just a few million records qualifies it as a broken feature.
    • Of course, the query optimizer/planner can be improved, but that's understandable and can be applied to pretty much any DBMS
  11. Sometimes the tool IS the problem by WebCowboy · · Score: 4, Insightful

    My point is that the tool is not always the problem. Now if C++'s integer arithmetic had an issue, that is another story, but the programmer simply was not good.

    No, the tool IS part of the problem in such cases. If the programmer was not that good at C then C was the wrong tool and thus part of the problem. The programmer should've taken the time to study up on C, or picked a different tool. There are times when the tool is not appropriate for the job--you probably shouldn't use C if you need to do heavy text processing and need to get the job done fast (use Perl instead), or if you are less experienced and want a language that supports sound object-oriented programming maybe try Python, etc.

    MySQL was not designed as a robust relational database, and its creators didn't seem to be intent on making it so, or else they'd have designed it differently. It was designed as a very quick and quite dirty SQL frontend/ISAM backend system to support small, informal databases (or so it seems): Basically, its heritage is to be like the old Ashton-Tate dBase but using SQL to query the tables. Since then it has lost that focus and now we have large websites storing millions of records in mySQL.

    MySQL is a great tool if used as intended, however it definitely IS a problem if your accounting system uses it for example. People started doing crap like that and complained about mySQL's lack of features, thus we have things tacked on like innoDB tables and such to add this robustness.

    PostgreSQL was not always as super-robust as it is now, and in its present form its source code is probably almost unrecognisable from 10 years ago, however its architecture was more sound and thought out from the start, as its heritage was as an academic project. Its challenge was not to add features as was the case with mySQL--PgSQL was designed for extensibility. PostgreSQL had to catch up in performance and stability, which it has done in spades.

    Personally, I always use UNIX timestamps (seconds since 1970). They can be directly added, sorted, and converted into any timezone, and its very portable. But thats just me. (Yes, UNIX timestamps do nothing before 1970, etc, etc).

    It seems somehow wrong that your business logic has to perform low-level validation of basic datatypes, and it is cumbersome and error-prone to deal with unrecognisable representations. Only the geekiest of geeks could tell me whether 1984293617 falls on a Thursday without runing it through some kind of conversion program (simple as that may be for a geek). What about people who point-and-click their way through some report designer--they're gonna have to deal with some giant integer in a column entitled "something-date". The other problem is that it is not very precise for some applications that need sub-second timestamp values.

    Personally, I like PostgreSQL because it accepts ISO standard formats, you don't need to do anything to convert timezones--you simply specify the time zone when you insert or query and it issmart enough to figure it out when you query fordatain Eastern time zone and it was inserted in Pacific timezone. Furthermore, it knows Feb 30 isn't valid, and knows when leap years occur, and can format the date in many different ways with simple built-in functions, can be accurate to the millisecond and won't crash and burn in 2038.

    FYI, I believe the "seconds since UNIX epoch" representation of date/time values is a SIGNED integer, so they are in fact good for earlier dates than 1970 (they are good to some time in late 1901 in fact). That is still a pretty limited range and why early systems didn't use that representation inmany cases (couldn't store birthdates for a lot of people who were still alive in the early 1970s becasue they were born before 1901). It is still a problem in some applications ad that is why 32-bit "UNIX-style" time is discouraged.

    I think it's a shame that people resort to such kludges without adequately lookig for more appropriate alternatives...but that's just me ;-)

  12. What an attitude by WebCowboy · · Score: 4, Insightful

    I can't be bothered to learn something new when it seems everything supports MySQL.

    I'm glad you don't work for me with that attitude. I'd rather work with someone who is interested in learning new things and will bring some creativity to the job. People of your mentality have to be careful they don't fall into the "false laziness" trap--using some tool or technique or techology because you are too lazy to learn something new, only to end up doing load of extra work to avoid the shortcomings of your inappropriate design choices. The result is scads of legacy code at higher layers of an application to handle things like datatype verification, basic referential integrity and so on.

    All the various different executables to do different tasks rather then one shell like MySQL, a permission system which seemed from my limited usage more perverse then MySQL's

    I've never found it to be a major struggle to use PostgreSQL, though being a more full-featured database it will naturally be a bit more complex to manage.
    I'm puzzled about the "all the various executables" part too, since many of them were invocable from the psql shell anyways. Also, it sounds like you've not lookded at PostgreSQL for awhile because its permissions system has undergone a lot of work--certainly it can be complex but it is very flexible and powerful, and honestly it gets rid of most excuses you had to execute all your database operations under the database superuser (or some other single user account) in your backend code.

    I have better things to do with my time, like write cool code that uses MySQL.

    You might want to examine how you used your time...if you had spent a few hours or a couple days learning something new for a change (like PostgreSQL) then it might've saved weeks or hours of frustration trying to use mySQL for too-complex tasks.

    MySQL might have grownup a lot in recent years, but at its heart it was meant for much more modest tasks, like storing guestbook entries, record collections, as a temporary datastore/embedded database, high-performance querying of relatively static ad/or non-critical data and so on.

  13. Comment removed by account_deleted · · Score: 5, Insightful

    Comment removed based on user account deletion