docs: json optimization

[b41sh]

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Summary

This PR adds a new RFC about JSON optimization

#6994

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[mergify]

This pull request's title is not fulfill the requirements. @b41sh please update it 🙏.

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fix(query): fix group by string bug
  ^         ^---------------------^
  |         |
  |         +-> Summary in present tense.
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  +-------> Type: feat, fix, refactor, ci, build, docs, website, chore

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[RinChanNOWWW]

Is there a more detail decscription about how FP-Growth algorithm is used here? As far as I know, the algorithm is mainly used for mining the MFI (Maximal Frequent Itemset) of a dataset.

[b41sh]

Is there a more detail decscription about how FP-Growth algorithm is used here? As far as I know, the algorithm is mainly used for mining the MFI (Maximal Frequent Itemset) of a dataset.

@RinChanNOWWW The idea comes from the paper JSON Tiles, we can use the FP-Growth algorithm to find frequently queried keys.