UNLINK

Asynchronously deletes one or more keys.

Browse all commands · Upstream source documentation

Reference field	Value
Canonical name	UNLINK
Catalog group	Generic commands
Upstream since	4.0.0 — upstream Redis/module version, not an ffkv release
Pinned catalog	Redis 8.10.0

Syntax

UNLINK key [key ...]

ffkv behavior and limits

TTL deadlines use wall-clock time and remain absolute across restart. Key/database operations can overwrite or remove data; SCAN is incremental rather than an atomic snapshot. New typed structures remain in RAM in hybrid mode.

Source: README.md:193–195, 375–377, 584–585; tests/bdd/features/generic.feature.

Data-changing administration: use an isolated dataset or a verified backup. Lost replies have an unknown outcome; never blindly replay a destructive operation.

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) for each key removed regardless of its size. Then the command does O(N) work in a different thread in order to reclaim memory, where N is the number of allocations the deleted objects where composed of.

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

Command flags: WRITE, FAST.

ACL categories: KEYSPACE.

Command tips: REQUEST_POLICY:MULTI_SHARD, RESPONSE_POLICY:AGG_SUM.

Argument structure

Argument	Type	Constraints / metadata
key	key	multiple; key_spec_index: 0

Key specifications

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

[
  {
    "flags": [
      "RM",
      "DELETE"
    ],
    "begin_search": {
      "index": {
        "pos": 1
      }
    },
    "find_keys": {
      "range": {
        "lastkey": -1,
        "step": 1,
        "limit": 0
      }
    }
  }
]

Additional pinned upstream metadata

{
  "group": "generic",
  "since": "4.0.0"
}

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

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.

• Existence counts repeated arguments but deletion counts each removed key once — tests/bdd/features/generic.feature:129; 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.

Existence counts repeated arguments but deletion counts each removed key once — tests/bdd/features/generic.feature:172 (I execute:)

[
  "UNLINK",
  "hash"
]

Next source assertion: the reply equals:

0

Existence counts repeated arguments but deletion counts each removed key once — tests/bdd/features/generic.feature:159 (I execute:)

[
  "UNLINK",
  "hash",
  "hash",
  "missing"
]

Next source assertion: the reply equals:

1