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VSIM.CREATEINDEX

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VSIM.CREATEINDEX index dims [METRIC COSINE | L2 | IP] [M m] [EF_CONSTRUCTION n] [EF_SEARCH n]
Group
Vector search
Complexity
O(1)
Arity
-3 (at least 3 words, counting the command name)
Flags
write, slow
Keys
first 1, last 1, step 1
HotKV Cloud
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On-Premise
no license needed

VSIM.CREATEINDEX creates an empty vector index called index for vectors of dims dimensions. You then store vectors under key names with VSIM.SET and find the closest ones to a query vector with VSIM.SEARCH. Searches are approximate (HNSW-indexed), which keeps them fast on large indexes.

Indexes and their vectors live beside the keyspace: KEYS, EXISTS and DEL do not see them, and an index name does not clash with a key of the same name. They are kept in snapshots. In cluster mode, an index lives on the node that owns the hash slot of its name.

Options

Section titled “Options”
Option Effect
METRIC COSINE Compare vectors by angle (the default). Good for text embeddings.
METRIC L2 Compare vectors by squared Euclidean distance.
METRIC IP Compare vectors by inner product (higher product means closer).
M m Index connectivity, 2 to 256 (a general-purpose default applies). Higher values improve search accuracy and use more memory.
EF_CONSTRUCTION n Build effort, at least 1 (a general-purpose default applies). Higher values build a more accurate index, more slowly.
EF_SEARCH n Default search effort, at least 1 (a general-purpose default applies). Higher values make searches more accurate and slower. Can be overridden per search with EF.

Metric names are case-insensitive. dims must be 1 to 65536.

Return value

Section titled “Return value”
Case RESP2 RESP3
Created Simple string OK Simple string OK

Error replies:

  • ERR index 'name' already exists
  • ERR invalid dimensions (must be 1-65536)
  • ERR invalid metric (use cosine, l2, or ip)
  • ERR invalid M parameter (must be 2-256)
  • ERR invalid EF_CONSTRUCTION (must be >= 1) and ERR invalid EF_SEARCH (must be >= 1)
  • ERR unknown option 'name'

An option name given last without a value is ignored.

Examples

Section titled “Examples”
127.0.0.1:6379> VSIM.CREATEINDEX docs 384
OK
127.0.0.1:6379> VSIM.CREATEINDEX points 3 METRIC L2 M 32 EF_SEARCH 100
OK
127.0.0.1:6379> VSIM.CREATEINDEX docs 384
(error) ERR index 'docs' already exists
127.0.0.1:6379> VSIM.INFO
1) "docs"
2) "points"

The order of the names VSIM.INFO lists can differ.

Compatibility

Section titled “Compatibility”

HotKV-only command. It is not related to the vector set commands (VADD, VSIM) of Redis 8.

See also

Section titled “See also”

VSIM.SET, VSIM.SEARCH, VSIM.INFO, VSIM.DROPINDEX