Integrity constraint
Integrity constraints are like rules that a database must obey so that all the data in it is correct and reliable. Think of it like a game with lots of rules. Let's say you're playing a game like tag. Some of the rules might be:
1. You can only tag people when they're moving - so you can't just stay where you are and tag people when they walk past.
2. You can't tag your friends if they haven't said it's okay.
Integrity constraints are the same, but for databases. They are rules that the database must follow so that all the information or data stored in it is accurate and makes sense. For example, a constraint could be that a person's age must be greater than 0 - so if someone tries to add a person with an age of -5, the database won't accept it because that would break the integrity constraint and it wouldn't make sense.
1. You can only tag people when they're moving - so you can't just stay where you are and tag people when they walk past.
2. You can't tag your friends if they haven't said it's okay.
Integrity constraints are the same, but for databases. They are rules that the database must follow so that all the information or data stored in it is accurate and makes sense. For example, a constraint could be that a person's age must be greater than 0 - so if someone tries to add a person with an age of -5, the database won't accept it because that would break the integrity constraint and it wouldn't make sense.
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