Copyright	(c) 2011-2012 Leon P Smith
License	BSD3
Maintainer	leon@melding-monads.com
Safe Haskell	None
Language	Haskell2010

Database.PostgreSQL.Simple.LargeObjects

Description

Support for PostgreSQL's Large Objects; see https://www.postgresql.org/docs/9.5/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.

Synopsis

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
- = AbsoluteSeek
- | RelativeSeek
- | SeekFromEnd

Documentation

loCreat :: Connection -> IO Oid Source #

loCreate :: Connection -> Oid -> IO Oid Source #

loImport :: Connection -> FilePath -> IO Oid Source #

loImportWithOid :: Connection -> FilePath -> Oid -> IO Oid Source #

loExport :: Connection -> Oid -> FilePath -> IO () Source #

loOpen :: Connection -> Oid -> IOMode -> IO LoFd Source #

loWrite :: Connection -> LoFd -> ByteString -> IO Int Source #

loRead :: Connection -> LoFd -> Int -> IO ByteString Source #

loSeek :: Connection -> LoFd -> SeekMode -> Int -> IO Int Source #

loTell :: Connection -> LoFd -> IO Int Source #

loTruncate :: Connection -> LoFd -> Int -> IO () Source #

loClose :: Connection -> LoFd -> IO () Source #

loUnlink :: Connection -> Oid -> IO () Source #

newtype Oid #

Constructors

Oid CUInt

Instances

Eq Oid
Instance details Defined in Database.PostgreSQL.LibPQ Methods (==) :: Oid -> Oid -> Bool # (/=) :: Oid -> Oid -> Bool #
Ord Oid
Instance details Defined in Database.PostgreSQL.LibPQ Methods compare :: Oid -> Oid -> Ordering # (<) :: Oid -> Oid -> Bool # (<=) :: Oid -> Oid -> Bool # (>) :: Oid -> Oid -> Bool # (>=) :: Oid -> Oid -> Bool # max :: Oid -> Oid -> Oid # min :: Oid -> Oid -> Oid #
Read Oid
Instance details Defined in Database.PostgreSQL.LibPQ Methods readsPrec :: Int -> ReadS Oid # readList :: ReadS [Oid] # readPrec :: ReadPrec Oid # readListPrec :: ReadPrec [Oid] #
Show Oid
Instance details Defined in Database.PostgreSQL.LibPQ Methods showsPrec :: Int -> Oid -> ShowS # show :: Oid -> String # showList :: [Oid] -> ShowS #
Storable Oid
Instance details Defined in Database.PostgreSQL.LibPQ Methods sizeOf :: Oid -> Int # alignment :: Oid -> Int # peekElemOff :: Ptr Oid -> Int -> IO Oid # pokeElemOff :: Ptr Oid -> Int -> Oid -> IO () # peekByteOff :: Ptr b -> Int -> IO Oid # pokeByteOff :: Ptr b -> Int -> Oid -> IO () # peek :: Ptr Oid -> IO Oid # poke :: Ptr Oid -> Oid -> IO () #
ToField Oid Source #
Instance details Defined in Database.PostgreSQL.Simple.ToField Methods toField :: Oid -> Action Source #
FromField Oid Source #	oid
Instance details Defined in Database.PostgreSQL.Simple.FromField Methods fromField :: FieldParser Oid Source #

data LoFd #

LoFd is a Large Object (pseudo) File Descriptor. It is understood by libpq but not by operating system calls.

Instances

Eq LoFd
Instance details Defined in Database.PostgreSQL.LibPQ Methods (==) :: LoFd -> LoFd -> Bool # (/=) :: LoFd -> LoFd -> Bool #
Ord LoFd
Instance details Defined in Database.PostgreSQL.LibPQ Methods compare :: LoFd -> LoFd -> Ordering # (<) :: LoFd -> LoFd -> Bool # (<=) :: LoFd -> LoFd -> Bool # (>) :: LoFd -> LoFd -> Bool # (>=) :: LoFd -> LoFd -> Bool # max :: LoFd -> LoFd -> LoFd # min :: LoFd -> LoFd -> LoFd #
Show LoFd
Instance details Defined in Database.PostgreSQL.LibPQ Methods showsPrec :: Int -> LoFd -> ShowS # show :: LoFd -> String # showList :: [LoFd] -> ShowS #

data IOMode #

See openFile

Constructors

ReadMode
WriteMode
AppendMode
ReadWriteMode

Instances

Enum IOMode
Instance details Defined in GHC.IO.IOMode Methods succ :: IOMode -> IOMode # pred :: IOMode -> IOMode # toEnum :: Int -> IOMode # fromEnum :: IOMode -> Int # enumFrom :: IOMode -> [IOMode] # enumFromThen :: IOMode -> IOMode -> [IOMode] # enumFromTo :: IOMode -> IOMode -> [IOMode] # enumFromThenTo :: IOMode -> IOMode -> IOMode -> [IOMode] #
Eq IOMode
Instance details Defined in GHC.IO.IOMode Methods (==) :: IOMode -> IOMode -> Bool # (/=) :: IOMode -> IOMode -> Bool #
Ord IOMode
Instance details Defined in GHC.IO.IOMode Methods compare :: IOMode -> IOMode -> Ordering # (<) :: IOMode -> IOMode -> Bool # (<=) :: IOMode -> IOMode -> Bool # (>) :: IOMode -> IOMode -> Bool # (>=) :: IOMode -> IOMode -> Bool # max :: IOMode -> IOMode -> IOMode # min :: IOMode -> IOMode -> IOMode #
Read IOMode
Instance details Defined in GHC.IO.IOMode Methods readsPrec :: Int -> ReadS IOMode # readList :: ReadS [IOMode] # readPrec :: ReadPrec IOMode # readListPrec :: ReadPrec [IOMode] #
Show IOMode
Instance details Defined in GHC.IO.IOMode Methods showsPrec :: Int -> IOMode -> ShowS # show :: IOMode -> String # showList :: [IOMode] -> ShowS #
Ix IOMode
Instance details Defined in GHC.IO.IOMode Methods range :: (IOMode, IOMode) -> [IOMode] # index :: (IOMode, IOMode) -> IOMode -> Int # unsafeIndex :: (IOMode, IOMode) -> IOMode -> Int inRange :: (IOMode, IOMode) -> IOMode -> Bool # rangeSize :: (IOMode, IOMode) -> Int # unsafeRangeSize :: (IOMode, IOMode) -> Int

data SeekMode #

A mode that determines the effect of hSeek hdl mode i.

Constructors

AbsoluteSeek	the position of `hdl` is set to `i`.
RelativeSeek	the position of `hdl` is set to offset `i` from the current position.
SeekFromEnd	the position of `hdl` is set to offset `i` from the end of the file.

Instances

Enum SeekMode
Instance details Defined in GHC.IO.Device Methods succ :: SeekMode -> SeekMode # pred :: SeekMode -> SeekMode # toEnum :: Int -> SeekMode # fromEnum :: SeekMode -> Int # enumFrom :: SeekMode -> [SeekMode] # enumFromThen :: SeekMode -> SeekMode -> [SeekMode] # enumFromTo :: SeekMode -> SeekMode -> [SeekMode] # enumFromThenTo :: SeekMode -> SeekMode -> SeekMode -> [SeekMode] #
Eq SeekMode
Instance details Defined in GHC.IO.Device Methods (==) :: SeekMode -> SeekMode -> Bool # (/=) :: SeekMode -> SeekMode -> Bool #
Ord SeekMode
Instance details Defined in GHC.IO.Device Methods compare :: SeekMode -> SeekMode -> Ordering # (<) :: SeekMode -> SeekMode -> Bool # (<=) :: SeekMode -> SeekMode -> Bool # (>) :: SeekMode -> SeekMode -> Bool # (>=) :: SeekMode -> SeekMode -> Bool # max :: SeekMode -> SeekMode -> SeekMode # min :: SeekMode -> SeekMode -> SeekMode #
Read SeekMode
Instance details Defined in GHC.IO.Device Methods readsPrec :: Int -> ReadS SeekMode # readList :: ReadS [SeekMode] # readPrec :: ReadPrec SeekMode # readListPrec :: ReadPrec [SeekMode] #
Show SeekMode
Instance details Defined in GHC.IO.Device Methods showsPrec :: Int -> SeekMode -> ShowS # show :: SeekMode -> String # showList :: [SeekMode] -> ShowS #
Ix SeekMode
Instance details Defined in GHC.IO.Device Methods range :: (SeekMode, SeekMode) -> [SeekMode] # index :: (SeekMode, SeekMode) -> SeekMode -> Int # unsafeIndex :: (SeekMode, SeekMode) -> SeekMode -> Int inRange :: (SeekMode, SeekMode) -> SeekMode -> Bool # rangeSize :: (SeekMode, SeekMode) -> Int # unsafeRangeSize :: (SeekMode, SeekMode) -> Int