JSON.ARRTRIM

    Trim an array so that it contains only the specified inclusive range of elements

    Required arguments

    is key to modify.

    path

    is JSONPath to specify. Default is root $.

    is index of the first element to keep (previous elements are trimmed). Default is 0.

    stop

    is the index of the last element to keep (following elements are trimmed), including the last element. Default is 0. Negative values are interpreted as starting from the end.

    About out-of-range indexes

    JSON.ARRTRIM is extremely forgiving, and using it with out-of-range indexes does not produce an error. Note a few differences between how RedisJSON v2.0 and legacy versions handle out-of-range indexes.

    Behavior as of RedisJSON v2.0:

    • If start is < 0, then start from the end of the array.
    • If stop is larger than the end of the array, it is treated like the last element.

    Return

    Trim an array to a specific set of values

    Create two headphone products with maximum sound levels.

    1. dragonfly> JSON.SET key $
    3. OK

    Add new sound level values to the second product.

    Get the updated array.

    1. dragonfly> JSON.GET key $[1].max_level

    Keep only the values between the fifth and the ninth element, inclusive of that last element.

    Get the updated array.

    1. dragonfly> JSON.GET key $[1].max_level
    2. "[[140,160,180,200,220]]"

    See also