Mordsith•4w ago

Add a query filter for empty value

This is a proposal to make querying for empty values easier. Handling all possible edge cases There should be a query filter to handle possible empty values; in situations where we need to unset a property and filter by this property, this filter should consider all possible falsey value, something similar to lodash's isEmpty https://lodash.com/docs/4.17.15#isEmpty This may be opionionated but I think there are a few people who see value in this... For array types => [] For object => {} For string "" (not to be confused with " ", an empty space; We can consider both instance as falsey but I need to hear people's suggestions if this makes sense) For numbers => 0 It should also apply to null, undefined and NaN Instead of doing things like this

await ctx.db
  .query('users')
  .filter((q) =>
    q.or(
      q.neq(q.field('shouldDeleteAt'), null),
      q.eq(q.field('shouldDeleteAt'), undefined),
    ),
  )
  .collect();

await ctx.db
  .query('users')
  .filter((q) =>
    q.or(
      q.neq(q.field('shouldDeleteAt'), null),
      q.eq(q.field('shouldDeleteAt'), undefined),
    ),
  )
  .collect();

This new approach is cleaner and would automatically handle edge cases. When the field is an object and this object is empty, it returns as part of the results; for an array, when it's empty or the length is 0, this also applies; same with null, undefined, false and 0

await ctx.db
  .query('users')
  .filter((q) =>
    q.isEmpty(q.field('shouldDeleteAt')),
  )
  .collect();

await ctx.db
  .query('users')
  .filter((q) =>
    q.isEmpty(q.field('shouldDeleteAt')),
  )
  .collect();

Open to questions and why this may not be a good thing. More: https://developer.mozilla.org/en-US/docs/Glossary/Falsy

MDN Web Docs

Falsy - MDN Web Docs Glossary: Definitions of Web-related terms | MDN

A falsy (sometimes written falsey) value is a value that is considered false when encountered in a Boolean context.

1 Reply

alixi•4w ago

you could write your own helper for this, something like:

const isEmpty = (q, field) =>
  q.or(
    q.eq(q.field(field), undefined),
    q.eq(q.field(field), null),
    // etc
  );

await ctx.db
  .query('users')
  .filter(q => isEmpty(q, 'shouldDeleteAt'))
  .collect();

const isEmpty = (q, field) =>
  q.or(
    q.eq(q.field(field), undefined),
    q.eq(q.field(field), null),
    // etc
  );

await ctx.db
  .query('users')
  .filter(q => isEmpty(q, 'shouldDeleteAt'))
  .collect();

Add a query filter for empty value

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