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ReQL command: sum

Command syntax

sequence.sum([field | function]) → number
r.sum(sequence, [field | function]) → number

Description

Sums all the elements of a sequence. If called with a field name, sums all the values of that field in the sequence, skipping elements of the sequence that lack that field. If called with a function, calls that function on every element of the sequence and sums the results, skipping elements of the sequence where that function returns null or a non-existence error.

Returns 0 when called on an empty sequence.

Example: What’s 3 + 5 + 7?

r.expr(r.array(3, 5, 7)).sum().run(conn);

Example: How many points have been scored across all games?

r.table("games").sum("points").run(conn);

Example: How many points have been scored across all games, counting bonus points?

r.table("games").sum(
    game -> game.g("points").add(game.g("bonus_points"))
).run(conn);

Related commands

  • map
  • reduce
  • count
  • avg
  • min
  • max
  • group

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Licensed under the Creative Commons Attribution-ShareAlike 3.0 Unported License.
https://rethinkdb.com/api/java/sum/

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