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Minimal Key Set is NP hard

It usually gives us a chuckle when we find some natural and seemingly easy data science question is NP-hard. For instance we have written that variable pruning is NP-hard when one insists on finding a minimal sized set of variables (and also why there are no obvious methods for exact large permutation tests).

In this note we show that finding a minimal set of columns that form a primary key in a database is also NP-hard.

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Posted on Categories Coding, OpinionTags , , , , , , 4 Comments on Take Care If Trying the RPostgres Package

Take Care If Trying the RPostgres Package

Take care if trying the new RPostgres database connection package. By default it returns some non-standard types that code developed against other database drivers may not expect, and may not be ready to defend against.


Danger

Danger, Will Robinson!

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