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Pacharapol Withayasakpunt
Pacharapol Withayasakpunt

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What are UNIQUE index limitations?

MongoDB will throw an error if string indices are being too large.

For SQLite, you can indeed create a unique index on DESCRIPTION, or VARCHAR(VERY_LONG) fields, and probably not throw an error; but are you really willing to accept the consequence?

Even for non-unique indices, probably not all indices helps querying performance that much?

Now that I looked it up, I don't even understand most of the terms.

  • Bitmap index
  • Dense index
  • Sparse index
  • Reverse index
  • Primary index
  • Secondary index

Even for MongoDB and nedb, there are choices of Unique Indices, whether sparse or not.

Now, I am curious on how to design a strongly typed database, with good querying performance, especially if flat and involves minimal joins?

  • About being well-typed, maybe Nitrite is a good one?
  • Well-defined schema can potentially help with typing, but how? Definitely not SQLite, though.
    • I like to work with Node.js, so TypeScript? What about the popular Golang?
    • Does well-defined schema help with performance?

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