The Phobia List provides an exhaustive list of phobias. Although it is difficult for many of us to understand or relate with many of these phobias, some are all too easy or me to understand. For example, I fear that I suffer at least mild cases of demophobia (fear of crowds) and homilophobia (fear of sermons). However, one fear that I see with a relatively high degree of occurrence in the software development community is the seemingly irrational (to me) fear of SQL.
The fear of SQL is so rampant that Ritesh Shah has named his blog "Fight the Fear of SQL." Other posts/comments indicating the prevalence of this fear of SQL include a Ruby on Rails related comment, a .NET related blog post, and in this Hibernate versus iBatis presentation (Java).
There have been numerous attempts at abstracting away or hiding SQL from the developer. The object-relational mapping (ORM) approach is probably the largest of these efforts in terms of person hours invested. This approach attempts to allow developers to focus on objects and their mappings to relational database structures (such as tables and columns) with the hope that the developer will never (or at least much less often) have to read, write, or maintain SQL.
Early Enterprise JavaBeans (EJB) container-managed persistence [CMP] (and especially container-managed relationships [CMR]) was a disaster by nearly all accounts. Not only was it more difficult (for most of us) to use than using SQL directly, but its (EJB 2's) EJB Query Language looked and felt suspiciously like SQL made worse by embedding it in XML. In fact, it's my contention that the much easier-to-use Java EE 5/6 with JPA is as popular as it could be because of these highly memorable negative experiences with its predecessors.
Another ORM example that was received much better in the Java community is Hibernate. Hibernate and the Spring Framework became a very common (if not THE most common) stack for Java-based applications at least in part because they were perceived as being easier to use than SQL/JDBC and J2EE. However, not everyone loves Hibernate as evidenced with posts such as Hibernate is crazy, iBATIS is awesome.
Overall, I'm a fan of JPA as I hope I made clear in my article Basic JPA Best Practices. I like the ability to relatively easily tie my normal Java objects into the transaction support of the supporting application server. Also, I think its advantageous to have a standardized approach to ORM rather than using a proprietary solution such as pre-JPA Hibernate. With all the positives of JPA, I still find there are times when it either is more than I need or when the impact it has on my object design is too great to justify. Furthermore, I have found the ability to be able to read SQL invaluable in debugging problems with my code that uses JPA implementations. In other words, I still need to know and be comfortable with SQL, even when using JPA implementations.
There are situations where even the best ORM implementation introduces more trouble and requires more effort than using SQL directly (such as via JDBC) or using a less intrusive technology (such as iBATIS). This seems to be especially true for complex data structures or for data designs that do not fit "the norm." Ted Neward has referred to object/relational mapping as the Vietnam of Computer Science. Aldo Cortesi's post A Farewell to ORMs provides excellent coverage of his moving away from use of ORMs in Python.
Regarding ORMs, Tim Bray has written, "ORM Blecch: My relationship with relational databases has always been chilly, but that’s a lot better than my relationship with object-relational mapping, which has never given me anything but pain. The one route to unambiguous success in ORM seems to be the Rails’ tactic of slashing flexibility."
I recall an interesting keynote Tim Bray gave at Colorado Software Summit 2004 where he basically asserted that we're all paid enough, trained enough, and smart enough to be able to work with SQL without need for an ORM. The interesting this is that wasn't even the point he was trying to make. He was actually trying to say the same thing for object-to-XML mapping and was using ORM almost as a given as a thing we don't always need. Mike Keith has provided a more thorough summary of this keynote and some good counter arguments. This keynote caused Mike to start writing a blog!
ORMs are a huge, but not the only, example of trying to avoid using SQL. Other examples include efforts like Java Data Objects (JDO), object databases, and XML databases. JDO had some promise but its future largely ended with what it contributed to JPA. Early on in my career, I used an object-oriented database called Versant that I actually really liked, but in general object-oriented databases have not taken much of the market share from relational databases. Similarly, XML databases already seem to have peaked without coming anywhere near the popularity of the relational database.
A very popular (in the blogosphere) alternative to SQL these days is the NoSQL concept. When I first read this term, my initial reaction was a rolling of the eyes and thinking "Here we go again." The name NoSQL is a little bit of a misnomer. If all it was about was not needing to use SQL, I would dismiss it immediately given the many available alternatives to SQL and to the fact that SQL itself is just not that difficult. I don't know much about NoSQL, but the thing that prevents me from immediately dismissing the notion is the primary cited motive for NoSQL. Despite the poorly chosen name, NoSQL really seems to be about moving away from the relational database rather than simply not using the Structured Query Language. That may or may not be a good idea and the alleged scalability benefits of NoSQL might be debated, but at least it's not grounded in the irrational fear of SQL.
Where does this irrational fear of SQL come from? I actually have experienced this myself. My undergraduate degree was in electrical and computer engineering. Although I took several computer science courses as part of my computer emphasis, there were some classes I did not get to take in the CS department. One general area I did not get any exposure to was SQL. In my first job out of college, I was somewhat intimidated by just the talk of SQL. However, one of my first projects had me working with SQL on a regular basis and I soon learned that it wasn't so bad.
Today, I have spoken with very bright, talented young developers who maintain nasty ORM mapping files with no problem, but fear that they cannot learn SQL/JDBC. I try to explain to them that the SQL is no more difficult than the mappings they are endeavoring to maintain, especially in the cases of "weird" or complex data needs. They fear the unknown.
There are real issues with SQL. Perhaps the biggest for me is the lack of any truly implemented standard. Some might argue that there is a SQL standard, but I have come to believe that a standard is only as good as its implementations. If the major and popular implementations poorly implement the standard or ignore it altogether, most of the value of having a "standard" is forfeited (it's not really standard in that case). Design patterns such as the Data Access Object were created to deal with this, but there is no question that Rails and ORMs that provided migrations capabilities have the upper hand here. In situations where multiple database vendors are used or are likely to be used, the lack of standardization in SQL can make its use truly scary.
Another commonly alleged drawback to SQL is that it requires learning different syntax and semantics than the programming language being used with SQL. This would be a bigger issue to me if basic SQL was as complex as learning the basics of a new programming language. In fact, I have benefited more than once from having the commonality of SQL to lean against while writing a database access piece of code in a new programming language. For example, it was pretty easy to learn how to apply Ruby to my database needs because of my knowledge of SQL.
In a world where polygot programming is the trend and many believe it wise to be comfortable with at least one statically typed language and one dynamically typed language, it seems obvious to me that it's in the best interest of developers to gain some degree of comfort with SQL as well. It's still one of the most likely languages a developer will actually use in his or her career. The side benefit of becoming more comfortable with SQL is that comfort and familiarity will often drive out the irrational fear.
Software developers are (typically) too well-trained to limit themselves due to fear. The best software developers are able to think critically about their architectures, designs, and implementations and about their choices of languages, products, libraries, and frameworks. JPA implementations have provided exactly what I need in many situations. However, JDBC/SQL implementations (especially with Spring) have also been my best bet in several cases. When one removes irrational fear, one can make the correct choice for the situation. With irrational fear present, one's ability to choose correctly is significantly impeded.
I have tried to come up with a witty name of the phobia describing the irrational "fear of SQL." Sequelphobia seems to already be taken for fear of movie sequels ("The Empire Strikes Back" might cure that) or video game sequels. Because fear of SQL is often correlated with not knowing SQL, I thought about xenophobia, but that has a negative cultural/political emphasis that I don't want to drag into this discussion. For now, I'm going to go with calling it "Sqlphobia." I welcome suggestions for a better name.
Basic SQL is not that difficult. I have seen DBAs and people with far more SQL experience than I have do amazingly tricky and complex things with SQL, but I find that simple SQL covers a large percentage of my needs. JDBC makes using SQL much easier than it used to be with proprietary approaches such as Pro*C/C++ precompiler and Spring+JDBC makes use of SQL even easier. The .NET community and other language/platform ecosystems typically have similarly easy-to-use SQL support as well.
In the end, I don't believe that straight JDBC/SQL is the best choice for every project. Some of the alternatives mentioned here are superior choices given certain conditions. However, I do think that an irrational fear of SQL is demonstrated when one spends much more time shoehorning a non-SQL solution into a place where it doesn't fit well simply to avoid having to use SQL.
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