K. Tsang CEng MBCS PMP PMI-ACP OCMJEA OCPJP
abhishek kunal wrote:i am often confused about which dbms to use for jdbc. learning it specifically for any dbms is certainly a limitation to that particular dbms. or in layman words i don't know how to study jdbc, please suggest me some way...i believe there are dbms specific issues and methods.so how to do an independent but still comprehensive study of jdbc....
dR
Fred Hamilton wrote:The good thing about JDBC is, it doesn't really matter which DBMS you use.
[OCP 11 Complete Study Guide] [OCP 11 Programmer I Book] [OCP 11 Programmer II Book] [OCP 11 Practice Tests Book] [OCA 8 Book] [OCP 8 Book] [OCP 8 Practice Tests Book] [Blog]
VAMSI MOHAN.V
(SCJP5.0, IBM Rational Solution Designer, IBM Rational Architect, IBM RUP Designer)
Scott Selikoff wrote:
Fred Hamilton wrote:The good thing about JDBC is, it doesn't really matter which DBMS you use.
I wish that were true, I really do. The fact of the matter is 99% of all JDBC-based applications *CANNOT* be easily ported to a different database without at least 1 (or 10,000) query 'tweaks'.
[OCP 17 book] | [OCP 11 book] | [OCA 8 book] [OCP 8 book] [Practice tests book] [Blog] [JavaRanch FAQ] [How To Ask Questions] [Book Promos]
Other Certs: SCEA Part 1, Part 2 & 3, Core Spring 3, TOGAF part 1 and part 2
Scott Selikoff wrote:
Fred Hamilton wrote:The good thing about JDBC is, it doesn't really matter which DBMS you use.
I wish that were true, I really do. The fact of the matter is 99% of all JDBC-based applications *CANNOT* be easily ported to a different database without at least 1 (or 10,000) query 'tweaks'. The only advice I can give you is never rely on built-in functions or syntax that seems db-dependent, you'll dig your own grave every time. On the other hand... generally object-relational mapping solutions like Hiberate/JDO are more easily ported because the developer almost never writes any queries.
Fred Hamilton wrote:surely the tweaks you speak of aren't java tweaks, but tweaks to SQL embedded in java. In other words, if all DBMS systems conformed to to SQL standards, there really would be no issue. agreed?
[OCP 11 Complete Study Guide] [OCP 11 Programmer I Book] [OCP 11 Programmer II Book] [OCP 11 Practice Tests Book] [OCA 8 Book] [OCP 8 Book] [OCP 8 Practice Tests Book] [Blog]
Scott Selikoff wrote:
Fred Hamilton wrote:surely the tweaks you speak of aren't java tweaks, but tweaks to SQL embedded in java. In other words, if all DBMS systems conformed to to SQL standards, there really would be no issue. agreed?
I wish the tweaks to be in java, that's often more manageable then trying to rewrite a 5-6 (or 30) line query. As for conforming to SQL standards, that's a dream I gave up on a long time ago. I think it was around the time I learned how to make a sequence for performing an auto-increment value in Oracle, or perhaps it was when I read tens of thousands of lines of code that used functions like nvl(), getdate(), now(), etc. In short, I have yet to come across a JDBC application with more than 10 queries that can be easily ported to a different database. It really takes an object-relational mapping tool to have a portable database-based application, since most developers are just not that disciplined.
Back to the original subject, I do think the database matters to some degree when learning. What you need to keep in mind is how you do things in one system may not match how you do things in others. Syntax can change among DBMS, and some are far better then others at certain things. My general rule of thumb, though, is this:
For simple applications and learning, use MySQL; for gigantic applications with millions of transactions a day, use Oracle; if you're stuck with Microsoft, use MS SQL Server.
I have tried many others, but unless you have a specific need (like an embedded DB), those are the top 3.
Fred Hamilton wrote:I hope we can all agree that MS Access is a bad choice? It's my understanding that it is notorious for non-standard SQL, at least it used to be.
[OCP 11 Complete Study Guide] [OCP 11 Programmer I Book] [OCP 11 Programmer II Book] [OCP 11 Practice Tests Book] [OCA 8 Book] [OCP 8 Book] [OCP 8 Practice Tests Book] [Blog]
[OCP 11 Complete Study Guide] [OCP 11 Programmer I Book] [OCP 11 Programmer II Book] [OCP 11 Practice Tests Book] [OCA 8 Book] [OCP 8 Book] [OCP 8 Practice Tests Book] [Blog]
With a little knowledge, a cast iron skillet is non-stick and lasts a lifetime. |