INCREX

Increments the numeric value of a key by a number and sets its expiration time. Uses 0 as initial value if the key doesn’t exist.

Browse all commands · Upstream source documentation

Reference field	Value
Canonical name	INCREX
Catalog group	String commands
Upstream since	8.8.0 — upstream Redis/module version, not an ffkv release
Pinned catalog	Redis 8.10.0

Syntax

INCREX key [BYFLOAT increment | BYINT increment]
 [LBOUND lowerbound] [UBOUND upperbound] [SATURATE]
 [EX seconds | PX milliseconds | EXAT unix-time-seconds| PXAT unix-time-milliseconds | PERSIST] [ENX]

ffkv behavior and limits

Keys and values are binary-safe bytes. Conditional SET and DELEX comparisons use the stored bytes; DIGEST uses XXH3, not a cryptographic digest.

Source: README.md:571–585; src/engine/strings.rs; tests/bdd/features/strings.feature.

All requests share the 8 MiB framing/1,024-argument ingress limit; normal RESP replies have 64 MiB wire/logical budgets with bounded nesting/value counts. Management and Lua origins impose smaller budgets. These are not a process RSS cap. Catalog inclusion is not exhaustive option or wire-format parity. See limits and compatibility.

Upstream metadata

The following fields come from the pinned Redis metadata, not measured ffkv performance or an assertion that ffkv enforces every upstream flag. Running COMMAND INFO/COMMAND DOCS describe the current engine.

Upstream Redis complexity: O(1)

Upstream arity: -2 (includes the command name; a negative number is a minimum).

Command flags: WRITE, DENYOOM, FAST.

ACL categories: STRING.

Argument structure

Argument	Type	Constraints / metadata
key	key	key_spec_index: 0
increment	oneof	optional
↳ float	double	token: BYFLOAT
↳ integer	integer	token: BYINT
saturate	pure-token	optional; token: SATURATE; summary: Saturate the result to LBOUND/UBOUND (or the type limits when no explicit bound is given) when out of bounds. Without this option, out-of-bounds operations are rejected and reply [current_value, 0].
lowerbound	string	optional; token: LBOUND; summary: Integer when used with BYINT, floating-point when used with BYFLOAT.
upperbound	string	optional; token: UBOUND; summary: Integer when used with BYINT, floating-point when used with BYFLOAT.
expiration	oneof	optional
↳ seconds	integer	token: EX
↳ milliseconds	integer	token: PX
↳ unix-time-seconds	unix-time	token: EXAT
↳ unix-time-milliseconds	unix-time	token: PXAT
↳ persist	pure-token	token: PERSIST
enx	pure-token	optional; token: ENX; summary: Only set the expiration if the key currently has no TTL. Requires one of EX/PX/EXAT/PXAT; cannot be combined with PERSIST.

Key specifications

Upstream key discovery descriptors (indexes are relative to the full command vector):

[
  {
    "flags": [
      "RW",
      "ACCESS",
      "UPDATE"
    ],
    "begin_search": {
      "index": {
        "pos": 1
      }
    },
    "find_keys": {
      "range": {
        "lastkey": 0,
        "step": 1,
        "limit": 0
      }
    }
  }
]

Additional pinned upstream metadata

{
  "group": "string",
  "since": "8.8.0"
}

Metadata source · Local snapshot: src/command_metadata.json, key increx.

BDD coverage and source examples

These are source observations, not a test run performed by this documentation build. A tag identifies scenario intent; an extracted vector identifies a command invocation, which may intentionally produce an error. Scenarios may require setup, multiple connections, persistence, cluster nodes or native-module fixtures.

• Bounded increments reject without changing expiration then saturate — tests/bdd/features/strings.feature:344; command tag and invocation observed.
• Duplicate options and unrepresentable saturated delta do not mutate — tests/bdd/features/strings.feature:1001; command tag and invocation observed.
• Resolved multi string writes survive crash recovery with their expiration — tests/bdd/features/strings.feature:1043; command tag and invocation observed.
• An applied bounded increment invalidates a watching transaction — tests/bdd/features/strings.feature:1092; command tag and invocation observed.
• String type errors never destroy a collection (Scenario Outline) — tests/bdd/features/strings.feature:1139; command tag and invocation observed.

Extracted command vectors

The following JSON arrays are the test harness’s argument vectors, not shell commands. Numeric arguments are converted by the harness; objects of the form {"base64":"…"} represent decoded binary bytes, not a literal JSON command argument. Preserve scenario setup and connection ordering. See the CLI guide for shell quoting and binary stdin. No reply is invented or inferred.

Bounded increments reject without changing expiration then saturate — tests/bdd/features/strings.feature:390 (I execute:)

[
  "INCREX",
  "counter",
  "BYFLOAT",
  "0.25"
]

Next source assertion: the reply equals:

["100.25","0.25"]

An applied bounded increment invalidates a watching transaction — tests/bdd/features/strings.feature:1106 (I execute:)

[
  "INCREX",
  "counter",
  "BYINT",
  "1",
  "UBOUND",
  "10"
]

Next source assertion: the reply equals:

[6,1]

Resolved multi string writes survive crash recovery with their expiration — tests/bdd/features/strings.feature:1049 (I execute:)

[
  "INCREX",
  "counter",
  "BYINT",
  "5",
  "UBOUND",
  "100",
  "SATURATE"
]

Next source assertion: the reply equals:

[100,1]