How do you change constraints in PostgreSQL?

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Tags

1. #constraints
2. #against
3. #there
4. #current
5. #command
6. #parameters
7. #accomplish
8. #postgresql
9. #course
10. #change
11. #version
12. #supports
13. #alter
14. #constraint
15. #easiest
16. #desired
17. #postgres
18. #table