Tell me more ×
Stack Overflow is a question and answer site for professional and enthusiast programmers. It's 100% free, no registration required.
up vote 3 down vote favorite
1

What are the differences - features and performance - between MySQL and Oracle 11g? I would like to be able to make and educated choice between the two given a situation.

Note: Links to test will obviously help.

share|improve this question
Depends on which version. – BoltClock♦ Feb 10 '11 at 6:35
@BoltClock: Edited. 11g. – Jungle Hunter Feb 10 '11 at 6:38

closed as not constructive by Sachin Shanbhag, cherouvim, zerkms, Vincent Malgrat, Jeffrey Kemp Feb 10 '11 at 8:41

As it currently stands, this question is not a good fit for our Q&A; format. We expect answers to be supported by facts, references, or specific expertise, but this question will likely solicit debate, arguments, polling, or extended discussion. If you feel that this question can be improved and possibly reopened, see the FAQ for guidance.

3 Answers

up vote 4 down vote accepted

Things that MySQL is still lacking (that Oracle has)

  • deferrable constraints
  • check constraints
  • recursive queries
  • table functions
  • common table expressions
  • windowing functions
  • function based index
  • partial index
  • No MINUS (or INTERSECT) operator
  • very simple query optimizer when it comes to sub-selects
  • A lot of non-standard Syntax (|| is a logical or!)
  • no flashback
share|improve this answer
Yeah I especially hate MySQL's non-standard syntax :| – BoltClock♦ Feb 10 '11 at 8:10
1  
A couple more: table/index clusters, single table hash clusters, sequences as separate objects – Nils Weinander Feb 10 '11 at 8:24
1  
One more: execution plans for non-select statements – Jake Feasel Jun 10 '12 at 19:20
up vote 5 down vote

Very popular answer for StackOverflow:

Look at Wikipedia! :)

Another useful place to look for SQL features comparation:

Comparison of different SQL implementations by Troels.

Hope, you can find answers here ...

share|improve this answer
up vote 1 down vote

Apparently, MySQL can tell the difference between an empty VARCHAR and a NULL value :-)

That alone is enough for me to avoid Oracle.

share|improve this answer
1  
I always wonder why people need that distinction. There is no such thing as an "empty" integer or an "empty" date or an "empty" decimal value. So why is this needed for strings? And I see stuff like if (string == null || string.length() == 0) in a lot of applications all over the places. So apparently in the frontend a null string and an empty string are often treated equally. What I find more annoying is, that this behaviour is not consistent within Oracle. Sometimes it does not treat an empty string as null. – a_horse_with_no_name Feb 10 '11 at 7:48
3  
There is indeed a massive difference. The point of a NULL value is to indicate unknown or not-applicable. There's a difference between someone with no middle name and someone with an unknown middle name. These things may not matter to the DBA wanna-bes of the world but they're very important to those who understand the issues :-) – paxdiablo Feb 10 '11 at 8:24
So what's the equivalent of an empty string for an integer value? (And please don't say it's zero) – a_horse_with_no_name Feb 10 '11 at 9:19
1  
Well, there's no equivalent of an empty string for integers. Oracle only has that limitation for character data. By way of example with integers, consider the age of someone. NULL means you don't know, any other value means you do know and it's set to that value. If we extended Oracles limitations to integers, it would indeed not be able to tell the difference between 0 and NULL but, thankfully, Oracle's not quite that bad :-) – paxdiablo Feb 10 '11 at 9:53
I still don't see the absolute necessity to have an "empty string" when none of the other datatypes have it. What's so special about strings that they need two different ways of storing the absence of a value - whereas all other datatypes are happily used by everybody with just a single way of storing "nothing" (don't get me wrong: I think Oracle should indeed comply with the standard here, but still I find myself always resetting empty strings to null on other databases) – a_horse_with_no_name Feb 10 '11 at 10:54
show 2 more comments

Not the answer you're looking for? Browse other questions tagged or ask your own question.