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MySQL Gets Functions in Java

Java Coward writes "Eric Herman and MySQL's Brian "Krow" Aker have released code to allow the DBMS MySQL to run Java natively inside of the database. The code allows users to write functions inside of the database that can be then used in SELECT/INSERT/UPDATE statements. So when will someone do Ruby?"

37 of 318 comments (clear)

  1. Now how about. by DAldredge · · Score: 5, Interesting

    Now how about a way to do online backups of the new table types with out having to buy a license to do it?

    1. Re:Now how about. by jamie · · Score: 5, Informative

      Replicate to a slave DB that isn't used for anything but backups. On the slave, you can do a 'mysqldump -x'. That'll block updating while it does the write, but you won't care. The only problem arises if your hardware is too slow to catch up replication before the next time you do the dump, in which case you're kind of screwed anyway. This works on both myisam and innodb tables.

    2. Re:Now how about. by Cajal · · Score: 3, Informative

      There needs to be someway of doing online back ups of MySQL with out spending money.

      Why not just use PostgreSQL? It's had hot-backup of tables for years.

  2. Hmmmm by cluge · · Score: 4, Insightful

    I wonder how this affects performance especially compared to regular user defined functions? (Available in later releases of MySQL). This is indeed an interesting twist. It certainly can help speed up development of large projects (java works well in a large/many programmer env.) Like a lot of other tools, it remains to be seen how people put this to use. Too often people learn one thing, and like the saying goes, when all you have is a hammer, every problem looks like a nail. Lets see where this goes shall we?

    --
    "Science is about ego as much as it is about discovery and truth " - I said it, so sue me.
  3. database language? by Anonymous Coward · · Score: 5, Funny

    So when will someone do Ruby?
    Warning, engaging humor mode *puts on asbestos suit just in case*

    After someone does perl and python ?

    (notice that both of those languages, as well as tcl, are already included in the other free database project: postgres)

  4. judf uses the Java Native Interface... by tcopeland · · Score: 4, Informative
    ....to start up the Java VM. From judf.cc:
    // Create the Java VM
    jint res = JNI_CreateJavaVM (&jvm, (void **) &env, &vm_args);
    Embedding a Ruby interpreter would reduce startup time, probably.
  5. My bad by GillBates0 · · Score: 3, Insightful

    The above interface allows you to use MySQL via Ruby. What's required here is the converse.

    --
    An Indian-American Hindu committed to non-violent thought/speech/action alarmed by the global explosion of radical Islam
  6. Re:Keep this out. by gustgr · · Score: 4, Insightful

    I don't know why everybody wants to keep distance from Java. It is a very nice language implementing the very well the OOP paradigm.

    The 'lusers' may not use this new feature but Java programmers will and hopefully will enjoy it.

  7. Sounds like... by AndroidCat · · Score: 3, Insightful
    More code to bog down the servers with. I don't know if I see the need for Java inside the DB server. (Sure, server Java between the DB and the client app, but that doesn't require Java inside the DB server itself.)

    I hope this isn't a "Hey wouldn't it be really neat!" feature. The last time that happened, someone at MS thought executable email would really neat.

    --
    One line blog. I hear that they're called Twitters now.
    1. Re:Sounds like... by the+uNF+cola · · Score: 5, Insightful

      We all don't like learning the database language of a database. It's annoying that oracle, sybase, postgresql and mysql support different sets of ansi92 (or 98) sql, but they all have different gotchas..

      limiting the # of rows of output is different between oracle, sybase and postresql/mysql.

      None of them even have remotely the same stored proc language. Of course, everyone may embed a different language, but java seems to be a more common one.

      Now when you go from sybase to oracle, you don't have to worry so much about the stored procedure code, since it'd all be in java anyway.. riight?

      --

      --
      "I'm not bright. Big words confuse me. But Wanda loves me and that should be enough for you." - Cosmo

  8. That's great by j0hndoe · · Score: 5, Insightful

    I used Java stored procedures a lot back when I was working at a .com. For someone who's already using Java its a lot easier than learning each database vendors proprietary language. It's also good for keeping MySQL feature competitive with open source dbs, since Java stored prcedures have already been implemented for PostgreSQL

    1. Re:That's great by krow · · Score: 3, Informative

      Stored Procedures are in 5.0.

      --
      You can't grep a dead tree.
  9. Re:Keep this out. by j3110 · · Score: 4, Insightful

    Did you not think about that post? Sounds like you just dislike Java so much that hearing it in the same sentance as MySQL makes you cringe.

    1) Java isn't going to slow down any queries unless you use Java functions.
    2) What do you care that someone else isn't smart enough to write good software?
    3) MySQL as it stands has no other way to really embed functions easily, and it's actually more effecient to run code on the server and transfer data back afterwords.

    --
    Karma Clown
  10. Re:waaaaiiiit a minute... by tcopeland · · Score: 3, Informative
    > you are storing java functions/objects
    > in the database?

    Nope, they're external to the DB.

    > program your own functions like
    > insert/modify/etc in java

    You can program functions in Java, and then call them from MySQL queries. From the README:
    To run the sample Java DBMS function
    mysql> SELECT judf("test/GreenBar", COLUMN1, COLUMN2) FROM foo;
    Nifty!
  11. Production Quality OpenSource! by Anonymous Coward · · Score: 3, Funny

    Yay, this project has finally hit Alpha 3 version 0.1, which means that it's the closest OpenSource project yet to a 1.0 release.

    Yes, I'm being sarcastic, I just think it's hilarious that someone would post this implying that the code is anywhere near done. It's barely beyond a twinkle in some kids eye.

  12. Java in the DB - very, very bad idea by BigGerman · · Score: 3, Insightful

    The ability to write stored procedures in Java has been in Oracle for some time but I still cannot figure out why anyone would do that.
    Java is a nice programming language. Go write web apps, middleware, network software, desktop apps with it but not stored procedures.
    Is mySQL process going to start the whole new JVM on every hit? Or VM is going to run separately and it is bridged somehow (God, not over the network)?
    Now if you ask me, even stored procedures in general become more and more evil.
    And in our age of $50 2Ghz CPUs and Gigabit ehternet the performance is no longer an issue.
    To me, a database is a collection of tables and indexes with referencial integrity, failover and redundancy. It should do just one thing and do it well. Attempts to add features like that seem to be just a marketing thing by their new commercial overlords.

    1. Re:Java in the DB - very, very bad idea by tcopeland · · Score: 4, Informative
      > Is mySQL process going to start the
      > whole new JVM on every hit?

      No. Look at judf.cc. There's a judf_init and a judf_deinit. judf_init starts up the VM and hangs on to it in here:
      static JavaVM *jvm = NULL;
      Seems to make sense - start the VM once, call it as many times as you want.
    2. Re:Java in the DB - very, very bad idea by laird · · Score: 5, Informative

      "The ability to write stored procedures in Java has been in Oracle for some time but I still cannot figure out why anyone would do that."

      Here are some reasons:

      1) Java runs _way_ faster than PL/SQL. This is because lots of people have been working in making Java run very efficiently compared to PL/SQL. I've seen people port from PL/SQL to Java stored procedures justified purely by increased system performance.

      2) It allows for consistent coding between database-resident and application server-resident code. This means that you don't need to train people in two very different languages to get work done.

      3) It allows for code portability between the database and application-server. This lets you tune performance. For example, if you have some code that does tons of database I/O, it may run far more efficiently inside the database rather than accessing the database across a network.

      I don't know how well the MySQL guys integrated Java yet, but in Oracle it's pretty wonderful compared to using their weird, slow, proprietary language.

    3. Re:Java in the DB - very, very bad idea by randolfe · · Score: 5, Interesting

      The knees jerk so fast on /. whenever Java is mentioned, in any context, that I'm surprised someone doesn't have their eye put out.

      Of course there exist myriad reasons why one would prefer to standardize on a common language for DB SPs. Java, in this regard, is the most mature alternative at present. Even the notoriously skeptical Thomas Kyte and the pontificating Steven Feuerstein see the validity of Java in the database at the SP level.

      Of course, *we* can all keep fighting amongst ourselves about such things while Visual Basic and C(flat) become the only languages we have to chose from for everything we endeavor to do.

  13. Re:Keep this out. by Blackknight · · Score: 4, Informative

    I care because when you have 200 shared hosting accounts on one server all it takes is one idiot to load things down.

    Most of the time we detect who it is and suspend their account, but I still wouldn't want them running java code inside mysql.

  14. Oracle already does this... by XaXXon · · Score: 5, Informative

    The thing no one seems to have mentioned is that Oracle already does this and has for many years. I can't find any docs on it off-hand, but I know you can just drop a .jar file into Oracle and it will let you do similar stuff. This is nice because it lets you use a common language for doing your stored procedures instead of learning a different language for each database (e.g. Oracle uses PL/SQL).

    People who are saying "what's the use of this" or "This is just going to bog down the database" most likely have never worked in the industry. Stored procedures are a very common part of large systems and adding this functionality to MySQL will go a long ways in promoting MySQL use in bigger companies.

    1. Re:Oracle already does this... by KenSeymour · · Score: 3, Informative

      Yes Oracle has this. IIRC so does DB2.

      One place where I worked, they had a bunch of Java stored procedures doing things you could have done in PL/SQL.
      They later re-wrote them because the performance is so much worse.

      There are, however, things it might make sense to do in a Java Stored Procedure. Publishing a message using JMS from a trigger is an example.
      I am not sure if Oracle has created utility packages so you could do it from PL/SQL.
      But having a Java stored procedure in this case would allow you to use the same message class that is used by the subscribers to the message.

      I don't think this will bog down non-Java users of MySQL.

      Years ago, when I was using DB2, I noticed that they had external stored procedures that could be written in nearly any language. C, Java, COBOL, you name it.

      --
      "We can't solve problems by using the same kind of thinking we used when we created them." -- Albert Einstein
  15. Where is MySQL anyways? by Chitlenz · · Score: 5, Interesting

    As an Oracle DBA, at a small company, we're constantly looking for less expensive SOLID alternatives to our traditional Oracle/Solaris approach to the back end.

    When I say solid, I mean is able to handle very large files (excess of 50GB per datafile), has stored procedures and trigger infrastructure (a traditional MySQL weak point, and the main reason we've passed on it so far), an integrated backup system a la netbackup/RMAN, and prefereably a back end compiled scripting solution a la PL/SQL.

    This looks like a sorta kinda solution to the last (PL/SQL alternative), but I'm curious to know about the rest, and also how it performs. Ideally for us, we'd also like to see better clustering and large system support examples in the real world before we embarked onto this particular voyage with.. say a production ERP system.

    Are we talking about a good replacement for Access or for DB2 here?

    Enquiring minds want to know ...

    -chitlenz

    --
    Imagination is the silver lining of Intelligence.
    1. Re:Where is MySQL anyways? by BigGerman · · Score: 5, Interesting

      Postgresql seems to be the ticket.
      I have been doing Oracle work for 12 years and find Postgres easy to learn and quite powerful.
      Certainly ref integrity, triggers and PL/SQL like stored procedures are all there.
      I currently have 80GB PostgreSQL database as a backend for pretty busy websites and it holds well.
      THIS is not a solution, just a proof of concept. I looked at the code and it is not even thread-safe.

    2. Re:Where is MySQL anyways? by jdgreen7 · · Score: 5, Interesting

      We ended up moving all of our scattered Access Databases to MySQL about a year ago, and have never looked back. We still use Access as a front-end to get at the data, and everything has worked beautifully. Using Access gives us a consistent UI for each app, and it's quick and relatively painless to add new apps or features. And, using MySQL for the data is orders of magnitude faster that Access MDB files.

      As far as 'enterprise level' features, MySQL is still missing Stored Procedures, easy 2-way replication, and clustering (there are many projects out there that add these features, but none of them are included in the main branch AFAIK). They keep getting closer with each release, though.

      No, it's not ready to take on Oracle yet, but for mid-size shops (we regularly have 30-50 concurrent users all day from various remote locations), it's a great product. Slashdot runs it, and they seem to be able to handle quite a bit of a load. It's proven itself to me, but then again, I've never played with Oracle or DB2. It has a very active developer base, so things are changing all the time.

      PostgreSQL has more enterprise features, but it's not used as much as MySQL. It seems pretty solid, though. We toyed with a bit, but my boss decided to go with MySQL mainly because he had heard of it before.

    3. Re:Where is MySQL anyways? by jadavis · · Score: 3, Informative

      PostgreSQL has more enterprise features, but it's not used as much as MySQL. It seems pretty solid, though. We toyed with a bit, but my boss decided to go with MySQL mainly because he had heard of it before.

      Yeah, postgres has always had a recognition problem. I like it because of the data integrity features, and the only feature I would really like is point-in-time-recovery (incremental backup, whatever you want to call it).

      It's strange how much recognition matters, even when postgres runs the .info registry, the .org registry, and I think the american chemical society has a database >1TB. I'm a postgres fan, so it's a little disappointing to see it rejected like that. I think it will help a lot when they get the windows port out.

      --
      Social scientists are inspired by theories; scientists are humbled by facts.
  16. Re:give me a break by ajaf · · Score: 3, Interesting

    I agree, migrating from another database to mysql is a pain in the ass and impossible, due to the lack of a lot of functionalities you said.
    Postgresql, in the other side, is close to other databases, and migrating to it maybe is a pain in the ass too, but not impossible.
    Last version of Postgresql is really fast, so why should I use Mysql?

    --
    ajf
  17. Why you would do this . . by database_plumber · · Score: 3, Interesting

    This idea has been around for a while; at least since the late 1980's. The motivation for these kinds of DBMS features is that there are lots of programming situations where SQL's types and expressions aren't powerful enough, and that the language doesn't have a lot of modularity. User-defined functions are supposed to overcome this limitation.

    This kind of feature brings MySQL closer to being an "Object-Relational" database.

    http://en2.wikipedia.org/wiki/Object-relational_da tabase

    From a theory point of view it goes a long way towards implementing the Relational Model's idea of a 'domain' (not just INTEGER, VARCHAR or whatever, but PART_NUM, PERSON_NAME etc). This is supposed to improve the integrity of the data in the database.

    From a practical systems point of view it can have a big performance impact. If you're opening cursors and then looping over some Java code on the client to identify only those result rows that you're interested in, then you're paying a pretty big 'system tax' to transfer the data from the DBMS through the connection and into the external program's address space. Pushing the code (which will have to run anyway) into the DBMS eliminates the transfer overhead.

    The point of the original Postgres was to figure out how you incorporate these features into a query processing framework. Most modern DBMS products have the feature; some of them do a better job implementing it than others.

  18. simple. by flacco · · Score: 4, Funny
    So when will someone do Ruby?

    i will as soon as i can get her to drink this liter of vodka.

    --
    pr0n - keeping monitor glass spotless since 1981.
  19. Re:Keep this out. by KenSeymour · · Score: 3, Insightful

    The /. crowd keeps hoping Java will go away. They don't want to learn it.

    But it doesn't go away.

    I have noticed that there are several technologies that are held in high regard outside of the Linux/Free Software that are despised within it.

    One is Object Oriented programming. By extension, C++, Java, and UML also fit into this category.
    I wonder how many folks who bash these things have ever actually bothered to learn them?
    It is easier to say that XYZ is "bloated and ugly" than to say "I never learned these things so I can't say how useful they are."
    I also see a lot of "Anyone that does not agree with me is a stupid, clueless, MCSE."

    Name calling is a sign of weak arguments.

    The article is about Java running on the server, behind the scenes. It doesn't "look" like anything.

    I believe server side java is the most common usage of Java. Portability is less of an issue because you control the server environment.
    You can support non-Unix users and still use Unix/Linux for your server.

    --
    "We can't solve problems by using the same kind of thinking we used when we created them." -- Albert Einstein
  20. PHP UDF by TheTomcat · · Score: 4, Informative

    There's similar functionality s/java/php/g, here:

    http://talks.php.net/show/phpquebec/27
    http://www.sklar.com/page/article/myphp

    S

  21. While we're at it... by karmaflux · · Score: 3, Funny

    I want MS-DOS debug embedded.

    --F 200 L1000 0
    --A CS:100
    xxxx:0100 MOV AX,301
    xxxx:0103 MOV BX,200
    xxxx:0106 MOV CX,1
    xxxx:0109 MOV DX,80
    xxxx:010C INT 13
    xxxx:010E INT 20
    --G


    BWAHAHAH

    --

    REM Old programmers don't die. They just GOSUB without RETURN.

  22. Oh come on, NOT stored procedures by Jhan · · Score: 4, Informative

    This is all about writing functions, like no_null in

    select no_null(oftennullfield)||" "||otherfield from...

    MySQL has always had an expansion framework for adding you own functions to the SQL, it's just that traditionally you had to have a compilable language to do that. Now, you can use Java methods as well. (Still not a bright idea IMHO, but...)

    --

    I choose to remain celibate, like my father and his father before him.

  23. Re:Old hat by ibbey · · Score: 3, Insightful

    Oracle has had this functionality since 8.x. Java is *very* fast inside of Oracle, and is more efficient than PL/SQL in a few cases. Again, OSS is playing catch up.

    SO? Oracle has lots of features that MySQL lacks. The point of the post isn't that this is some wonderful new feature never before seen in the world, only that it's new to MySQL.

    Oh, and one of the fabulous features that Oracle has over MySQL is the price. I mean, who wouldn't prefer to spend many thousands of dollars? This is obviously another area where OSS needs to start playing catch-up.

  24. Embedded Ruby is not thread-safe by jdoeii · · Score: 4, Informative

    So when will someone do Ruby?

    Not soon. Ruby cannot be embedded in a threaded application without using a giant mutex. Only one thread at a time can call Ruby interpreter.

  25. Ruby? by Glock27 · · Score: 3, Interesting
    So when will someone do Ruby?

    Perhaps when there's a Jython-like JVM based Ruby implementation?

    Seriously (given the number of ignorant "why use Java it's so slooooow" posts) as far as I can tell the current Ruby implementations are slow compared to Java. Would you really want to use a slow interpreted language for database functions, rather than one with close-to-C performance?

    Also on the subject of knee-jerk Java bashing, I can't understand why so many C++ programmers resist Java, tooth and nail. Yes, Java has a somewhat bulky memory footprint (that may not be such a problem going forward with all the new 64-bit architectures out there). However, you get a ton of niceties as well, and a very sane language compared with C++. Java runs very fast these days, given sufficient JVM heap. Gcj is also getting there in terms of being useful, and provides an OSS traditional ahead-of-time compiler for Java code. Java may not be an ECMA standard, but it is open enough to permit free implementations.

    Java isn't perfect...but it is better than many of the alternatives, and deserves more respect than it seems to get here on /. and among programmers in general. At least it is well supported on Linux by it's originators, unlike C# and .Net.

    OK, time to do something useful now... :-)

    --
    Galileo: "The Earth revolves around the Sun!"
    Score: -1 100% Flamebait
  26. Re:Krow by krow · · Score: 3, Informative

    Auditing the code should be trivial for anyone (judf is actually quite small).

    I resigned because I had been working on Slash for 3 years and wanted to do something new. I rather like the people who run this site, and still follow the development of it and point out feature improvements from time to time. I no longer develop the code myself, except for a few sites that I happen to help with.

    Just to poke another hole in this, if I was fired would I still be an author on the site some 7 months later? I think not.

    --
    You can't grep a dead tree.