| Maintainer | leon@melding-monads.com |
|---|---|
| Safe Haskell | None |
Database.PostgreSQL.Simple.LargeObjects
Description
Support for PostgreSQL's Large Objects; see http://www.postgresql.org/docs/9.1/static/largeobjects.html for more information.
Note that Large Object File Descriptors are only valid within a single database transaction, so if you are interested in using anything beyond loCreat, loCreate, and loUnlink, you will need to run the entire sequence of functions in a transaction. As loImport and loExport are simply C functions that call loCreat, loOpen, loRead, and loWrite, and do not perform any transaction handling themselves, they also need to be wrapped in an explicit transaction.
- loCreat :: Connection -> IO Oid
- loCreate :: Connection -> Oid -> IO Oid
- loImport :: Connection -> FilePath -> IO Oid
- loImportWithOid :: Connection -> FilePath -> Oid -> IO Oid
- loExport :: Connection -> Oid -> FilePath -> IO ()
- loOpen :: Connection -> Oid -> IOMode -> IO LoFd
- loWrite :: Connection -> LoFd -> ByteString -> IO Int
- loRead :: Connection -> LoFd -> Int -> IO ByteString
- loSeek :: Connection -> LoFd -> SeekMode -> Int -> IO Int
- loTell :: Connection -> LoFd -> IO Int
- loTruncate :: Connection -> LoFd -> Int -> IO ()
- loClose :: Connection -> LoFd -> IO ()
- loUnlink :: Connection -> Oid -> IO ()
- newtype Oid = Oid CUInt
- data LoFd
- data IOMode
- = ReadMode
- | WriteMode
- | AppendMode
- | ReadWriteMode
- data SeekMode
Documentation
loCreat :: Connection -> IO OidSource
loImportWithOid :: Connection -> FilePath -> Oid -> IO OidSource
loWrite :: Connection -> LoFd -> ByteString -> IO IntSource
loRead :: Connection -> LoFd -> Int -> IO ByteStringSource
loTruncate :: Connection -> LoFd -> Int -> IO ()Source
loClose :: Connection -> LoFd -> IO ()Source
loUnlink :: Connection -> Oid -> IO ()Source
newtype Oid
data LoFd
LoFd is a Large Object (pseudo) File Descriptor. It is understood by libpq but not by operating system calls.
data SeekMode
A mode that determines the effect of hSeek hdl mode i.
Constructors
| AbsoluteSeek | the position of |
| RelativeSeek | the position of |
| SeekFromEnd | the position of |