Today we have a problem with a compound primary key, which ensures that multiple column combinations are not unique. But in practice, it"s the opposite.
this is my table structure
1234
2,2,1:
wonder
Today we have a problem with a compound primary key, which ensures that multiple column combinations are not unique. But in practice, it"s the opposite.
this is my table structure
1234
2,2,1:
wonder
there seems to be something wrong with the mysql in the company. I went home and tried it. No such weird thing happened
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