TOPK.RESERVE

Syntax text Syntax diagram API methods

TOPK.RESERVE key topk [width depth decay]

Client:

reserve(
    key: str,
    k: int,
    width: int,
    depth: int,
    decay: float
) → bool  // True if the filter was created successfully

TOPK.RESERVE(
    key: RedisArgument,
    topK: number,
    options: TopKReserveOptions  // Optional: { width, depth, decay }
) → SimpleStringReply<'OK'>  // OK on success

topkReserve(
    key: String,
    topk: long
) → String  // OK

topkReserve(
    key: String,
    topk: long,
    width: long,
    depth: long,
    decay: double
) → String  // OK

TopKReserve(
    ctx: context.Context,
    key: string,
    k: int64
) → *StatusCmd  // Status command result

TopKReserveWithOptions(
    ctx: context.Context,
    key: string,
    k: int64,
    width: int64,
    depth: int64,
    decay: float64
) → *StatusCmd  // Status command result

Reserve(
    key: RedisKey,
    topk: long,
    width: long,  // Default: 7
    depth: long,  // Default: 8
    decay: double  // Default: 0.9
) → bool  // True if created successfully

ReserveAsync(
    key: RedisKey,
    topk: long,
    width: long,  // Default: 7
    depth: long,  // Default: 8
    decay: double  // Default: 0.9
) → Task<bool>  // True if created successfully

topkreserve(
    key: string,
    topk: int,
    width: int,  // Optional, default: 7
    depth: int,  // Optional, default: 8
    decay: float  // Optional, default: 0.9
) → string  // OK

Available in:: Redis Open Source / Bloom 2.0.0
Time complexity:: O(1)
ACL categories:: @topk, @write, @fast,
Compatibility:: Redis Software and Redis Cloud compatibility

Initializes a Top-K sketch with specified parameters.

Required arguments

key

the name of the Top-k sketch.

topk

the number of top (k) occurring items to keep.

Optional arguments

width

Number of counters kept in each array. (Default 8)

depth

Number of arrays. (Default 7)

decay

The probability of reducing a counter in an occupied bucket (decay ^ bucket[i].counter). As the counter gets higher, the likelihood of a reduction is lower. (Default 0.9)

Examples

redis> TOPK.RESERVE topk 50 2000 7 0.925
OK

Redis Software and Redis Cloud compatibility

Redis Software	Redis Cloud	Notes
✅ Supported	✅ Flexible & Annual ✅ Free & Fixed

Return information

RESP2 RESP3

One of the following:

Simple string reply OK if executed correctly.
Simple error reply in these cases: incorrect number of arguments, invalid decay value, or key already exists.