updated: 2022-01-23_12:32:31-05:00

Join

AKA Natural Join or Theta Join

Natural Join only shows rows where matching attributes are the same in both tables

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  • Essentially a Cartesian Product which matches Primary Key using Select

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  • The difference is this is more computationally intense but uses less memory, queries both tables before merging vs merging and filtering

There are two kinds: Natural and Theta

  • natural join does not have duplicate attributes

  • theta is natural join with a condition, BUT it does not remove duplicate attributes

  • Theta is basically the Cartesian Product with a condition

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