Differences between MySQL and Oracle DB [closed]

问题:

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Closed 9 years ago.

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.

回答1:

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

回答2:

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 ...

回答3:

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

That alone is enough for me to avoid Oracle.