Prevent duplicate record

Hi
I have a like table that have user_id and comment_id field
I need user only can like once each comment and i dont want to check it with SELECT
Maybe adjust table column that occur error when insert record?
Like primary error
I attach my table shot
I want only insert record example
user_id,comment_id
2,4

for next insert,show error for insert
Maybe?

There is no way to check it without using a select.

Code:

SELECT EXISTS(SELECT * FROM yourTableName WHERE yourCondition);

I would make sure that both columns are index.

What did you Try? What did you Get? What did you Expect?

Joined CodeIgniter Community 2009.  ( Skype: insitfx )

There is no way to check it without using a select.

Code:

SELECT EXISTS(SELECT * FROM yourTableName WHERE yourCondition);

I would make sure that both columns are index.

Thanks but
I remember we could implement this feature with add key on fields and prevent duplicate records
But i dont know how do it

Not sure but this might be what your looking for.

MySQL - Handling Duplicates

What did you Try? What did you Get? What did you Expect?

Joined CodeIgniter Community 2009.  ( Skype: insitfx )

Not sure but this might be what your looking for.

MySQL - Handling Duplicates

Thank you

---

Not sure but this might be what your looking for.

MySQL - Handling Duplicates

It's working good very thanks