ReQL command: max
Command syntax
sequence.max(field | function) → element sequence.max(index=<indexname>) → element r.max(sequence, field | function) → element r.max(sequence, index=<indexname>) → element
Description
Finds the maximum element of a sequence.
The max
command can be called with:
- a field name, to return the element of the sequence with the largest value in that field;
- an index (the primary key or a secondary index), to return the element of the sequence with the largest value in that index;
- a function, to apply the function to every element within the sequence and return the element which returns the largest value from the function, ignoring any elements where the function produces a non-existence error.
For more information on RethinkDB’s sorting order, read the section in ReQL data types.
Calling max
on an empty sequence will throw a non-existence error; this can be handled using the default command.
Example: Return the maximum value in the list [3, 5, 7]
.
r.expr([3, 5, 7]).max().run(conn)
Example: Return the user who has scored the most points.
r.table('users').max('points').run(conn)
Example: The same as above, but using a secondary index on the points
field.
r.table('users').max(index='points').run(conn)
Example: Return the user who has scored the most points, adding in bonus points from a separate field using a function.
r.table('users').max(lambda user:
user['points'] + user['bonus_points']
).run(conn)
Example: Return the highest number of points any user has ever scored. This returns the value of that points
field, not a document.
r.table('users').max('points')['points'].run(conn)
Example: Return the user who has scored the most points, but add a default None
return value to prevent an error if no user has ever scored points.
r.table('users').max('points').default(None).run(conn)
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https://rethinkdb.com/api/python/max/