mysql - INSERTING and UPDATING SQL tables -


How to INSERT the data in a table that is the key to a mistake? I tried to do this 

  Insert in City (name, country, population) values ​​("New Zealand", "Auckland", "80000");

However this has given me an error

# 1452 - The line of a child can not be added or updated: a foreign key constraint Failed ( stu_nall596_compsci_280_c_s2_2014 . city , CONSTRAINT city_ibfk_2 foreign key ( country ) reference country ( id ))

And in the period of updating an area, how to do it?

To ignore the fact that "New Zealand" is not a city, and "Auckland" is a city And not a country, if you want your involvement to be successful, then you have a line with a consistent id of "Auckland" in country Required entry will allow you to insert a new line in the city table for the city of that country.

I do not know how your schema looks, but this is a difficult example;

Enter Country (ID, Name) Price (123, 'New Zealand'); Include City (name, country, population) values ​​('Auckland', 123, 80000);

See before, I can refer to it, country in the id of 123 Must be present city table.


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