Database.Muesli.Handle

Database resource management.

Documentation

module Database.Muesli.Types

module Database.Muesli.Backend.Types

module Database.Muesli.Backend.File

data Handle l

Handle used for database management operations.

The l parameter stands for a LogState backend.

Instances

Eq (Handle l)

Show (Handle l)

open

Arguments

:: (MonadIO m, LogState l)

=> Maybe DbPath

Log path. Default is data/docdb.log.

-> Maybe DbPath

Data path. Default is data/docdb.dat.

-> Maybe (Int, Int, NominalDiffTime)

LRUCache parameters: (min cap in bytes, max cap in bytes, max age in seconds). Defaults are: (1MB, 10MB, 1min).

-> Maybe Int

Commit delay in microseconds. Default is 100ms.

-> m (Handle l)

Opens a database, reads the transaction log and builds the in-memory indexes.

The l parameter of the resulting Handle should be instantiated by the user in order to specify a backend. For example, to use the file backend:

import qualified Database.Muesli.Handle as DB

openDataBase :: FilePath -> FilePath -> IO (DB.Handle DB.FileLogState)
openDataBase logPath dataPath = open (Just logPath) (Just dataPath) Nothing Nothing

close :: (MonadIO m, LogState l) => Handle l -> m ()

Closes the database.

Since the database is ACID, calling close is not really necessary for consistency purposes.

performGC :: MonadIO m => Handle l -> m ()

Sends a message to the gcThread requesting GC.

debug

Arguments

:: (MonadIO m, LogState l)

=> Handle l

-> Bool

Dump indexes.

-> Bool

Dump the cache.

-> m String

A debug function that traces the internal DBState.