kv
get
Read the current or historical value for one KV key.
strata kv getdb.kv.get(key: 'str | bytes', *, as_of: 'Optional[int]' = None, as_of_time: 'Optional[TimeLike]' = None) -> 'Optional[bytes]'wire kv_get
Reads one KV key from the selected branch and space. The optional timestamp reads the value visible at that point in time when history is retained.
Optional reads distinguish present data from missing data. When version or timestamp facts exist on the executor output, SDK mappings should preserve them.
To see the complete help for this command, run:
strata kv get --helphelp(db.kv.get)
Example
Read a value back; a missing key returns nothing.
strata kv put greeting hellostrata kv get greetingstrata kv get absent
_ = db.kv.put("greeting", "hello")db.kv.get("greeting")db.kv.get("absent") is None
Parameters
| Name | Type | Required | Description |
|---|---|---|---|
| key | Bytes | yes | Key bytes. |
| as_of | integer or null | no | Read as of a position on the logical commit timeline - the `timestamp` from `history` output, not the `version`, and never a calendar date. To read as of a real time, use `as_of_time` instead. |
| as_of_time | integer or null | no | Read as of a real time: a wall-clock instant in microseconds since the Unix epoch (UTC), as reported by `committed_at` on a write ack or on any `history` row. Resolves to the commit at or before that instant, and fails rather than guessing if the instant falls outside the branch's recorded history. Mutually exclusive with `as_of`. |
| branch | string or null | no | Target branch. Defaults to the executor handle branch. |
| space | string or null | no | Target product space. Defaults to `"default"`. |
Returns
Maybe<VersionedValue>
- dataMaybe
- typestring
Errors
Recover by code. Retry policy and commit outcome come from the shipped error registry.
| Code | Retry | Commit outcome |
|---|---|---|
| failed_precondition.engine.runtime_closed | never | not_started |
| not_found.engine.branch | never | not_applicable |
| invalid_argument.engine.product_space | never | not_started |
| invalid_argument.engine.kv_key | never | not_started |
| history_unavailable.engine.persistence_history | after_state_change | not_applicable |