下表有三栏:
ID | table | article | 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
是否有可能用1份声明和如何做?
Thank you for your help in advance
这可为您的行文工作。
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)
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