mysql: if then else query

I have a table with 3 columns:

ID | table | artic开发者_开发知识库le | number
1     2        2        1  
2     3        4        4

What I need is a query which checks whether a combination of table and article already exists. For example (table 2 and article 2)

In this case number should be incremented by 1.

So it has to like like this now: 1 2 2 2

Otherwise (for example: table 2 and article 5) a new row should be created: 3 2 5 1

Is it possible to do this with 1 statement and how?

Thank you for your help in advance

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Check INSERT ... ON DUPLICATE KEY UPDATE Syntax

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This may work for you on your DB...

insert into theTable 
(ID, table, article, number) 
values (3, 2, 5, 1) 
where not exists    
(select ID 
from theTable 
where table = 2 and article = 5)