leveldb

Creates a new in-memory ordered key-value store. Keys are maintained in sorted (BTree) order, making range and prefix queries efficient.

use plugin leveldb::{LevelDB}

let db = LevelDB.new()

Inserts or updates a key with a string or bytes value. String values are stored as UTF-8 bytes internally.

use plugin leveldb::{LevelDB}

let db = LevelDB.new()
db.put("user:1", "Alice")
db.put("user:2", "Bob")

Retrieves the raw bytes stored at key. Returns nil if the key does not exist. Use get_string when you know the value is valid UTF-8.

let raw = db.get("user:1")

Retrieves the value at key as a UTF-8 string. Returns nil if the key does not exist. Errors if the stored bytes are not valid UTF-8.

use plugin leveldb::{LevelDB}

let db = LevelDB.new()
db.put("name", "Alice")
let name = db.get_string("name")
print("Hello, {name}")

Removes the entry at key. Does nothing if the key does not exist.

db.delete("user:2")

Returns true if key exists in the store.

use plugin leveldb::{LevelDB}

let db = LevelDB.new()
db.put("token", "abc")
if db.has("token") {
  print("Token found: {db.get_string("token")}")
}

Returns all keys in sorted lexicographic order as an array.

let all_keys = db.keys()
print("Keys: {all_keys}")

Returns all keys in the inclusive range [start, end] in sorted order. Useful for scanning a subset of entries, such as all keys with a common prefix.

use plugin leveldb::{LevelDB}

let db = LevelDB.new()
db.put("user:1", "Alice")
db.put("user:2", "Bob")
db.put("user:3", "Carol")
let range_keys = db.keys_range("user:1", "user:2")

Returns all keys that start with prefix, in sorted order.

let user_keys = db.prefix_keys("user:")

Returns all stored values as bytes, in key-sorted order.

let all_values = db.values()

Returns the total number of entries in the store.

let n = db.count()
print("Entries: {n}")

Removes all entries from the store, leaving it empty.

db.clear()

Exports all entries as a table mapping string keys to byte values. Useful for serializing the store's contents.

let snapshot = db.to_table()

Inserts multiple entries at once. Each entry in the entries table must be a table with key (string) and value (string or bytes) fields.

use plugin leveldb::{LevelDB}

let db = LevelDB.new()
db.batch_put([
  #{"key": "a", "value": "1"},
  #{"key": "b", "value": "2"},
  #{"key": "c", "value": "3"}
])
print("Count: {db.count()}")

Deletes multiple keys at once. The keys argument is a table (array) of key strings.

db.batch_delete(["a", "b"])