Struct KvStore 

pub struct KvStore<'conn> { /* private fields */ }

A handle to one named key-value store, backed by KV_TABLE.

Borrows its Connection for the handle’s lifetime ('conn), matching the crate’s Catalog/Inserter borrow convention. Open one with Connection::kv_store.

Examples

use hyperdb_api::{Connection, CreateMode, Result};

fn main() -> Result<()> {
    let conn = Connection::connect("localhost:7483", "app.hyper", CreateMode::CreateIfNotExists)?;
    let kv = conn.kv_store("settings")?;
    kv.set("theme", "dark")?;
    assert_eq!(kv.get("theme")?, Some("dark".to_string()));
    Ok(())
}

Implementations

impl<'conn> KvStore<'conn>

pub fn name(&self) -> &str

Returns this store’s validated name.

pub fn get(&self, key: &str) -> Result<Option<String>>

Returns the value for key, or None if the key is absent or NULL.

Errors

• Error::InvalidName if key is invalid.
• Error::FeatureNotSupported on gRPC transport.
• Error::Server if the query fails.

pub fn set(&self, key: &str, value: &str) -> Result<()>

Sets key to value, inserting or overwriting (upsert).

Errors

• Error::InvalidName if key is invalid.
• Error::FeatureNotSupported on gRPC transport.
• Error::Server if the UPDATE/INSERT fails.

pub fn get_as<T: DeserializeOwned>(&self, key: &str) -> Result<Option<T>>

Deserializes the JSON-encoded value for key into T.

Returns None if the key is absent.

Errors

• Error::InvalidName if key is invalid.
• Error::Serialization if the stored value is not valid JSON for T.
• Error::FeatureNotSupported / Error::Server as for get.

pub fn set_as<T: Serialize>(&self, key: &str, value: &T) -> Result<()>

Serializes value to JSON and stores it under key (upsert).

Errors

• Error::InvalidName if key is invalid.
• Error::Serialization if value cannot be serialized to JSON.
• Error::FeatureNotSupported / Error::Server as for set.

pub fn delete(&self, key: &str) -> Result<bool>

Deletes key; returns true if a row was removed.

Errors

• Error::InvalidName if key is invalid.
• Error::FeatureNotSupported / Error::Server.

pub fn exists(&self, key: &str) -> Result<bool>

Returns whether key is present in this store.

Errors

• Error::InvalidName if key is invalid.
• Error::FeatureNotSupported / Error::Server.

pub fn size(&self) -> Result<i64>

Returns the number of keys in this store.

Errors

• Error::FeatureNotSupported / Error::Server.

pub fn keys(&self) -> Result<Vec<String>>

Returns this store’s keys, sorted ascending.

Errors

• Error::FeatureNotSupported / Error::Server.

pub fn clear(&self) -> Result<u64>

Deletes every key in this store; returns the number removed.

The shared backing table survives; only this store’s rows are removed.

Errors

• Error::FeatureNotSupported / Error::Server.

pub fn pop(&self) -> Result<Option<(String, String)>>

Removes and returns the lowest-ordered key/value pair, or None if empty.

The peek and delete run in one transaction, so they apply atomically — either both the read and the delete commit, or neither does (on error the transaction is rolled back). A SQL-NULL value is returned as an empty string.

Errors

• Error::FeatureNotSupported / Error::Server.

pub fn set_batch(&self, entries: &[(&str, &str)]) -> Result<()>

Upserts every (key, value) pair in one transaction.

All keys are validated before the transaction opens, so an invalid key aborts the whole batch without writing anything.

Errors

• Error::InvalidName if any key is invalid (checked before writing).
• Error::FeatureNotSupported / Error::Server.

Trait Implementations

impl<'conn> Debug for KvStore<'conn>

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.