Thanks, these videos are short and to the point which helps a lot when I just want to check out some specific concepts for a project that I'm working on and I have to use MySQL
Caleb, could you explain is it possible or acceptable to create a foreign key to a field in another table and this field is a foreign key which references to a primary key in another table yet? For example a table `cities` has a field called `cities`.`region_id` which is foreign key to table `regions` (field `regions`.`id`) and a table `stations` has a field `stations`.`region_id` which is foreign key to table `cities` and references to `cities`.`region_id` but not `regions.id`? Thank you for your videos! They are very useful!
One clear example of this could be a comments table that stores comments submitted by users in a social network. Each user can comment more than once on a single post, but every comment must always reference its author
Thanks, these videos are short and to the point which helps a lot when I just want to check out some specific concepts for a project that I'm working on and I have to use MySQL
4:36 Somebody has got to get Batman a foreign key for his birthday
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thank you!
that was exactly what i were looking for
Caleb, could you explain is it possible or acceptable to create a foreign key to a field in another table and this field is a foreign key which references to a primary key in another table yet? For example a table `cities` has a field called `cities`.`region_id` which is foreign key to table `regions` (field `regions`.`id`) and a table `stations` has a field `stations`.`region_id` which is foreign key to table `cities` and references to `cities`.`region_id` but not `regions.id`?
Thank you for your videos! They are very useful!
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Bro your videos are the best, you have a talent at explaining thing. Thanks you =)
Helpful lecture. Good job!
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Can you tell me how to filter data in both parent and child tables using the primary key?
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Great video, Caleb!
happy new year
it's little confusing at 3:00 and 4:30. At 3:00 u made two references and at 4;30 u said only one ref. can be made, please explain
The 'Unique' constraint is optional. If you set it, then a parent can't have more than one child. Otherwise, it's possible.
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That first example was not very good but the rest worked fine
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Thank you a lots (Y).
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Golden
why do you have two children with ID 7 reference to same parent? (3:00)
One clear example of this could be a comments table that stores comments submitted by users in a social network. Each user can comment more than once on a single post, but every comment must always reference its author
great example. thx mate
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watching this in 2017.
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you are awesome
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