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No ORM

Why index-first?

Why does no-orm enforce that you write an index before you can query by that column on a table?

Pros and cons of an index

Section titled “Pros and cons of an index”

There are pros and cons of creating a database index.

  • Pro (faster read times): Traversing a B-Tree has logarithmic time complexity compared to the tree size, so the benefit you receive from having this index is exponential.
  • Con (Slower write times): Inserting a new element into a B-Tree has logarithmic time complexity so the cost paid to write-times due to this index is also logarithmic.
  • Con (Storage): Every new row in the table increases the B-Tree size by the same amount therefore this cost is linear.

Below is a plot showing how the benefits and costs of an index change as a table grows.

Pros and cons of an index.

In most read-heavy applications, the pros outweigh the cons at all sizes of your table. So why would you not just add an index?

This is why no-orm encourages you to think about your indexes before querying a table via that column.