Forgot your password?
typodupeerror
Databases Programming

Moving From CouchDB To MySQL 283

Posted by Unknown Lamer
from the hep-cats-just-use-postgres dept.
itwbennett writes "Sauce Labs had outgrown CouchDB and too much unplanned downtime made them switch to MySQL. With 20-20 hindsight they wrote about their CouchDB experience. But Sauce certainly isn't the first organization to switch databases. Back in 2009, Till Klampaeckel wrote a series of blog posts about moving in the opposite direction — from MySQL to CouchDB. Klampaeckel said the decision was about 'using the right tool for the job.' But the real story may be that programmers are never satisfied with the tool they have." Of course, then they say things like: "We have a TEXT column on all our tables that holds JSON, which our model layer silently treats the same as real columns for most purposes. The idea is the same as Rails' ActiveRecord::Store. It’s not super well integrated with MySQL's feature set — MySQL can’t really operate on those JSON fields at all — but it’s still a great idea that gets us close to the joy of schemaless DBs."
This discussion has been archived. No new comments can be posted.

Moving From CouchDB To MySQL

Comments Filter:
  • by Sarten-X (1102295) on Wednesday May 16, 2012 @09:47AM (#40016109) Homepage

    That's actually a rather insightful point...

    If your application fits well with the methodologies of a traditional RDBMS, use a traditional RDBMS, and hire people who are trained and experienced in using those methodologies to their full potential.

    If you're dealing with the latest Big Data paradigms and designs, where you can sacrifice some of the rigidity of a RDBMS to gain some flexibility and cheaper scalability, use a NoSQL database, and hire people who aren't stuck in their old RDBMS ways.

  • Why not PostgreSQL? (Score:5, Interesting)

    by JamesA (164074) on Wednesday May 16, 2012 @09:48AM (#40016117)
  • Nosql in Postgres (Score:4, Interesting)

    by rla3rd (596810) on Wednesday May 16, 2012 @09:48AM (#40016123)
    You can get json support using the PLV8 extension http://code.google.com/p/plv8js/wiki/PLV8 [google.com]

    or altenatively you can use the hstore data type.
  • by Viol8 (599362) on Wednesday May 16, 2012 @10:00AM (#40016255)

    It seems to be a knee jerk reaction amongst a lot of developers and designers that as soon as your app starts requiring persistent data beyond ini values a database is needed. Why? For large but simply structured data something like json or XML or even a flat csv file is perfectly adequate. Performance can be an issue during searches but if for example you have a fixed record size with key sorted data then finding a given key is simple (binary chop or similar).

    It seems to me that reaching for a DB is the easy way out taken by a lot of oders and they end up paying for it in maintanability, bugs and support.

  • by mj1856 (589031) on Wednesday May 16, 2012 @10:30AM (#40016643)

    Not sure about MongoDB or CouchDB, but I have experience with RavenDB, which is absolutely fantastic. Instead of "joins" you have "includes" or "live projections". See http://ravendb.net/docs/client-api/querying/handling-document-relationships [ravendb.net]

  • Urban Airship (Score:4, Interesting)

    by jjohnson (62583) on Wednesday May 16, 2012 @10:33AM (#40016685) Homepage

    Urban Airship went PostgreSQL to MongoDB to Cassandra to PostgreSQL. http://wiki.postgresql.org/images/7/7f/Adam-lowry-postgresopen2011.pdf [postgresql.org]

    It's a good presentation because they're in love with none of them and are moving for specific reasons each time, handling different issues. It's not coders chasing the new hotness.

  • Re:Not getting RDMS (Score:5, Interesting)

    by K. S. Kyosuke (729550) on Wednesday May 16, 2012 @11:41AM (#40017611)

    There's absolutely no reason to change SQL, because if you build a new query language that is based on the same mathematically sound principles of relational algebra then it will er... look just like SQL.

    False. First of all, SQL is NOT based on mathematically sound principles of relational algebra. SQL took the mathematically sound principles of relational algebra and fucked them up. There should be no NULLs, there should be no natural ordering of "columns", there should be no possibility of having duplicate rows, there should be no possibility of inconsistent intermediate states in transactions (no deferred checking) etc. SQL has them all, and then some. Why? Because SQL simply ignores the relation model and "does what IBM and Oracle always did". That's not the same thing as "implementing the relational model".

    Second, there is a separation between the surface structures of a language and its foundations. I really don't think that a language based on relational algebra has to look like SQL. That's like saying that a language with nouns having singular and plural and verbs having tenses has to look like English. Nope, it doesn't have to at all. Just look and VB.NET and C#. Basically two front-ends to a virtually identical language semantics, only one of them does not avoid non-alphabetic structural delimiters like the plague (and is so much more pleasant for it).

  • Re:Not getting RDMS (Score:5, Interesting)

    by TheRealMindChild (743925) on Wednesday May 16, 2012 @12:32PM (#40018163) Homepage Journal
    There should be no NULLs
    Then how do I, say, indicate the date of death for someone who hasn't died? An IsDead field? Really? (Yes, a NULL in a field is a shortcut for proper relationship, but a lack of relationship when using a linking table will still be represented by NULL)

    there should be no natural ordering of "columns"
    Does it really matter? The natural ordering of columns is the order in which you added them to the table. Ignore it. It isn't important, and not in need of a "solution"

    there should be no possibility of having duplicate rows
    Firstly, get to know your DISTINCT SQL keyword. Secondly, data in real life sometimes IS duplicate. What the hell should people do? Have a DuplicatedThisManyTimes field? Ugh.

    possibility of inconsistent intermediate states in transactions
    That is a property of the database engine, not SQL.

    Because SQL simply ignores the relation model and "does what IBM and Oracle always did". That's not the same thing as "implementing the relational model".
    Where do you get this shit? Are you telling me the function of foreign key constraints and referential integrity, and the good ol INNER/RIGHT/LEFT join keywords are just smoke and mirrors and everything is really just a chaotic bowl of soup? References please.

It is better to give than to lend, and it costs about the same.

Working...