-- Hoogle documentation, generated by Haddock -- See Hoogle, http://www.haskell.org/hoogle/ -- | Mid-Level SQLite client library -- -- Mid-level SQLite client library, based on postgresql-simple. -- -- Main documentation: Database.SQLite.Simple -- -- For more info, browse to http://github.com/nurpax/sqlite-simple -- for examples & more information. @package sqlite-simple @version 0.4.2.0 -- | The Ok type is a simple error handler, basically equivalent to -- Either [SomeException]. -- -- One of the primary reasons why this type was introduced is that -- Either SomeException had not been provided an instance for -- Alternative, and it would have been a bad idea to provide an -- orphaned instance for a commonly-used type and typeclass included in -- base. -- -- Extending the failure case to a list of SomeExceptions enables -- a more sensible Alternative instance definitions: -- <|> concatinates the list of exceptions when both cases -- fail, and empty is defined as 'Errors []'. Though -- <|> one could pick one of two exceptions, and throw away -- the other, and have empty provide a generic exception, this -- avoids cases where empty overrides a more informative exception -- and allows you to see all the different ways your computation has -- failed. module Database.SQLite.Simple.Ok data Ok a Errors :: [SomeException] -> Ok a Ok :: !a -> Ok a -- | a way to reify a list of exceptions into a single exception newtype ManyErrors ManyErrors :: [SomeException] -> ManyErrors instance Typeable1 Ok instance Typeable ManyErrors instance Show a => Show (Ok a) instance Functor Ok instance Show ManyErrors instance Exception ManyErrors instance Monad Ok instance MonadPlus Ok instance Alternative Ok instance Applicative Ok instance Eq a => Eq (Ok a) -- | Internal bits. This interface is less stable and can change at any -- time. In particular this means that while the rest of the -- sqlite-simple package endeavors to follow the package versioning -- policy, this module does not. Also, at the moment there are things in -- here that aren't particularly internal and are exported elsewhere; -- these will eventually disappear from this module. module Database.SQLite.Simple.Internal -- | Connection to an open database. -- -- You can use connectionHandle to gain access to the underlying -- http://hackage.haskell.org/package/direct-sqlite connection. -- This may be useful if you need to access some direct-sqlite -- functionality that's not exposed in the sqlite-simple API. This should -- be a safe thing to do although mixing both APIs is discouraged. newtype Connection Connection :: Database -> Connection connectionHandle :: Connection -> Database -- | A Field represents metadata about a particular field data Field Field :: SQLData -> {-# UNPACK #-} !Int -> Field result :: Field -> SQLData column :: Field -> {-# UNPACK #-} !Int newtype Row Row :: [SQLData] -> Row rowresult :: Row -> [SQLData] newtype RowParser a RP :: ReaderT Row (StateT Int Ok) a -> RowParser a unRP :: RowParser a -> ReaderT Row (StateT Int Ok) a gettypename :: SQLData -> ByteString instance Functor RowParser instance Applicative RowParser instance Alternative RowParser instance Monad RowParser -- | Top-level module for sqlite-simple. module Database.SQLite.Simple.Types -- | A placeholder for the SQL NULL value. data Null Null :: Null -- | A single-value "collection". -- -- This is useful if you need to supply a single parameter to a SQL -- query, or extract a single column from a SQL result. -- -- Parameter example: -- --
--   query c "select x from scores where x > ?" (Only (42::Int))
--   
-- -- Result example: -- --
--   xs <- query_ c "select id from users"
--   forM_ xs $ \(Only id) -> {- ... -}
--   
newtype Only a Only :: a -> Only a fromOnly :: Only a -> a -- | A query string. This type is intended to make it difficult to -- construct a SQL query by concatenating string fragments, as that is an -- extremely common way to accidentally introduce SQL injection -- vulnerabilities into an application. -- -- This type is an instance of IsString, so the easiest way to -- construct a query is to enable the OverloadedStrings language -- extension and then simply write the query in double quotes. -- --
--   {-# LANGUAGE OverloadedStrings #-}
--   
--   import Database.SQLite.Simple
--   
--   q :: Query
--   q = "select ?"
--   
-- -- The underlying type is a Text, and literal Haskell strings -- that contain Unicode characters will be correctly transformed to -- UTF-8. newtype Query Query :: Text -> Query fromQuery :: Query -> Text -- | A composite type to parse your custom data structures without having -- to define dummy newtype wrappers every time. -- --
--   instance FromRow MyData where ...
--   
-- --
--   instance FromRow MyData2 where ...
--   
-- -- then I can do the following for free: -- --
--   res <- query' c ...
--   forM res $ \(MyData{..} :. MyData2{..}) -> do
--     ....
--   
data (:.) h t (:.) :: h -> t -> :. h t instance Typeable Null instance Typeable Query instance Typeable1 Only instance Typeable2 :. instance Read Null instance Show Null instance Eq Query instance Ord Query instance Eq a => Eq (Only a) instance Ord a => Ord (Only a) instance Read a => Read (Only a) instance Show a => Show (Only a) instance Functor Only instance (Eq h, Eq t) => Eq (h :. t) instance (Ord h, Ord t) => Ord (h :. t) instance (Show h, Show t) => Show (h :. t) instance (Read h, Read t) => Read (h :. t) instance Monoid Query instance IsString Query instance Read Query instance Show Query instance Eq Null -- | The FromField typeclass, for converting a single value in a row -- returned by a SQL query into a more useful Haskell representation. -- -- A Haskell numeric type is considered to be compatible with all SQLite -- numeric types that are less accurate than it. For instance, the -- Haskell Double type is compatible with the SQLite's 32-bit -- Int type because it can represent a Int exactly. On -- the other hand, since a Double might lose precision if -- representing a 64-bit BigInt, the two are not -- considered compatible. module Database.SQLite.Simple.FromField -- | A type that may be converted from a SQL type. class FromField a fromField :: FromField a => FieldParser a type FieldParser a = Field -> Ok a -- | Exception thrown if conversion from a SQL value to a Haskell value -- fails. data ResultError -- | The SQL and Haskell types are not compatible. Incompatible :: String -> String -> String -> ResultError errSQLType :: ResultError -> String errHaskellType :: ResultError -> String errMessage :: ResultError -> String -- | A SQL NULL was encountered when the Haskell type did not -- permit it. UnexpectedNull :: String -> String -> String -> ResultError errSQLType :: ResultError -> String errHaskellType :: ResultError -> String errMessage :: ResultError -> String -- | The SQL value could not be parsed, or could not be represented as a -- valid Haskell value, or an unexpected low-level error occurred (e.g. -- mismatch between metadata and actual data in a row). ConversionFailed :: String -> String -> String -> ResultError errSQLType :: ResultError -> String errHaskellType :: ResultError -> String errMessage :: ResultError -> String -- | A Field represents metadata about a particular field data Field -- | Return the actual SQL data for a database field. This allows -- user-defined FromField instances to access the SQL data -- associated with a field being parsed. fieldData :: Field -> SQLData -- | Given one of the constructors from ResultError, the field, and -- an errMessage, this fills in the other fields in the exception -- value and returns it in a 'Left . SomeException' constructor. returnError :: (Typeable a, Exception err) => (String -> String -> String -> err) -> Field -> String -> Ok a instance Typeable ResultError instance Eq ResultError instance Show ResultError instance FromField Day instance FromField UTCTime instance FromField ByteString instance FromField ByteString instance FromField [Char] instance FromField Text instance FromField Text instance FromField Bool instance FromField Double instance FromField Integer instance FromField Int64 instance FromField Int instance FromField Int32 instance FromField Int16 instance FromField Null instance FromField a => FromField (Maybe a) instance Exception ResultError -- | The FromRow typeclass, for converting a row of results returned -- by a SQL query into a more useful Haskell representation. -- -- Predefined instances are provided for tuples containing up to ten -- elements. module Database.SQLite.Simple.FromRow -- | A collection type that can be converted from a sequence of fields. -- Instances are provided for tuples up to 10 elements and lists of any -- length. -- -- Note that instances can defined outside of sqlite-simple, which is -- often useful. For example, here's an instance for a user-defined pair: -- --
--   data User = User { name :: String, fileQuota :: Int }
--   
--   instance FromRow User where
--        fromRow = User <$> field <*> field
--   
-- -- The number of calls to field must match the number of fields -- returned in a single row of the query result. Otherwise, a -- ConversionFailed exception will be thrown. -- -- Note the caveats associated with user-defined implementations of -- fromRow. class FromRow a fromRow :: FromRow a => RowParser a data RowParser a field :: FromField a => RowParser a fieldWith :: FieldParser a -> RowParser a numFieldsRemaining :: RowParser Int instance (FromRow a, FromRow b) => FromRow (a :. b) instance FromField a => FromRow [a] instance (FromField a, FromField b, FromField c, FromField d, FromField e, FromField f, FromField g, FromField h, FromField i, FromField j) => FromRow (a, b, c, d, e, f, g, h, i, j) instance (FromField a, FromField b, FromField c, FromField d, FromField e, FromField f, FromField g, FromField h, FromField i) => FromRow (a, b, c, d, e, f, g, h, i) instance (FromField a, FromField b, FromField c, FromField d, FromField e, FromField f, FromField g, FromField h) => FromRow (a, b, c, d, e, f, g, h) instance (FromField a, FromField b, FromField c, FromField d, FromField e, FromField f, FromField g) => FromRow (a, b, c, d, e, f, g) instance (FromField a, FromField b, FromField c, FromField d, FromField e, FromField f) => FromRow (a, b, c, d, e, f) instance (FromField a, FromField b, FromField c, FromField d, FromField e) => FromRow (a, b, c, d, e) instance (FromField a, FromField b, FromField c, FromField d) => FromRow (a, b, c, d) instance (FromField a, FromField b, FromField c) => FromRow (a, b, c) instance (FromField a, FromField b) => FromRow (a, b) instance FromField a => FromRow (Only a) -- | The ToField typeclass, for rendering a parameter to an SQLite -- value to be bound as a SQL query parameter. module Database.SQLite.Simple.ToField -- | A type that may be used as a single parameter to a SQL query. class ToField a toField :: ToField a => a -> SQLData instance ToField Day instance ToField UTCTime instance ToField Text instance ToField [Char] instance ToField Text instance ToField ByteString instance ToField ByteString instance ToField Double instance ToField Float instance ToField Word64 instance ToField Word instance ToField Word32 instance ToField Word16 instance ToField Word8 instance ToField Integer instance ToField Int64 instance ToField Int instance ToField Int32 instance ToField Int16 instance ToField Int8 instance ToField Bool instance ToField Null instance ToField a => ToField (Maybe a) instance ToField SQLData -- | The ToRow typeclass, for rendering a collection of parameters -- to a SQL query. -- -- Predefined instances are provided for tuples containing up to ten -- elements. module Database.SQLite.Simple.ToRow -- | A collection type that can be turned into a list of SQLData elements. class ToRow a toRow :: ToRow a => a -> [SQLData] instance (ToRow a, ToRow b) => ToRow (a :. b) instance ToField a => ToRow [a] instance (ToField a, ToField b, ToField c, ToField d, ToField e, ToField f, ToField g, ToField h, ToField i, ToField j) => ToRow (a, b, c, d, e, f, g, h, i, j) instance (ToField a, ToField b, ToField c, ToField d, ToField e, ToField f, ToField g, ToField h, ToField i) => ToRow (a, b, c, d, e, f, g, h, i) instance (ToField a, ToField b, ToField c, ToField d, ToField e, ToField f, ToField g, ToField h) => ToRow (a, b, c, d, e, f, g, h) instance (ToField a, ToField b, ToField c, ToField d, ToField e, ToField f, ToField g) => ToRow (a, b, c, d, e, f, g) instance (ToField a, ToField b, ToField c, ToField d, ToField e, ToField f) => ToRow (a, b, c, d, e, f) instance (ToField a, ToField b, ToField c, ToField d, ToField e) => ToRow (a, b, c, d, e) instance (ToField a, ToField b, ToField c, ToField d) => ToRow (a, b, c, d) instance (ToField a, ToField b, ToField c) => ToRow (a, b, c) instance (ToField a, ToField b) => ToRow (a, b) instance ToField a => ToRow (Only a) instance ToRow () module Database.SQLite.Simple -- | A query string. This type is intended to make it difficult to -- construct a SQL query by concatenating string fragments, as that is an -- extremely common way to accidentally introduce SQL injection -- vulnerabilities into an application. -- -- This type is an instance of IsString, so the easiest way to -- construct a query is to enable the OverloadedStrings language -- extension and then simply write the query in double quotes. -- --
--   {-# LANGUAGE OverloadedStrings #-}
--   
--   import Database.SQLite.Simple
--   
--   q :: Query
--   q = "select ?"
--   
-- -- The underlying type is a Text, and literal Haskell strings -- that contain Unicode characters will be correctly transformed to -- UTF-8. newtype Query Query :: Text -> Query fromQuery :: Query -> Text -- | Connection to an open database. -- -- You can use connectionHandle to gain access to the underlying -- http://hackage.haskell.org/package/direct-sqlite connection. -- This may be useful if you need to access some direct-sqlite -- functionality that's not exposed in the sqlite-simple API. This should -- be a safe thing to do although mixing both APIs is discouraged. newtype Connection Connection :: Database -> Connection connectionHandle :: Connection -> Database -- | A collection type that can be turned into a list of SQLData elements. class ToRow a toRow :: ToRow a => a -> [SQLData] -- | A collection type that can be converted from a sequence of fields. -- Instances are provided for tuples up to 10 elements and lists of any -- length. -- -- Note that instances can defined outside of sqlite-simple, which is -- often useful. For example, here's an instance for a user-defined pair: -- --
--   data User = User { name :: String, fileQuota :: Int }
--   
--   instance FromRow User where
--        fromRow = User <$> field <*> field
--   
-- -- The number of calls to field must match the number of fields -- returned in a single row of the query result. Otherwise, a -- ConversionFailed exception will be thrown. -- -- Note the caveats associated with user-defined implementations of -- fromRow. class FromRow a fromRow :: FromRow a => RowParser a -- | A single-value "collection". -- -- This is useful if you need to supply a single parameter to a SQL -- query, or extract a single column from a SQL result. -- -- Parameter example: -- --
--   query c "select x from scores where x > ?" (Only (42::Int))
--   
-- -- Result example: -- --
--   xs <- query_ c "select id from users"
--   forM_ xs $ \(Only id) -> {- ... -}
--   
newtype Only a Only :: a -> Only a fromOnly :: Only a -> a -- | A composite type to parse your custom data structures without having -- to define dummy newtype wrappers every time. -- --
--   instance FromRow MyData where ...
--   
-- --
--   instance FromRow MyData2 where ...
--   
-- -- then I can do the following for free: -- --
--   res <- query' c ...
--   forM res $ \(MyData{..} :. MyData2{..}) -> do
--     ....
--   
data (:.) h t (:.) :: h -> t -> :. h t data SQLData :: * SQLInteger :: !Int64 -> SQLData SQLFloat :: !Double -> SQLData SQLText :: !Text -> SQLData SQLBlob :: !ByteString -> SQLData SQLNull :: SQLData -- | An SQLite prepared statement. data Statement -- | Index of a column in a result set. Column indices start from 0. newtype ColumnIndex ColumnIndex :: ColumnIndex -> ColumnIndex -- | Open a database connection to a given file. Will throw an exception if -- it cannot connect. -- -- Every open must be closed with a call to close. -- -- If you specify ":memory:" or an empty string as the input filename, -- then a private, temporary in-memory database is created for the -- connection. This database will vanish when you close the connection. open :: String -> IO Connection -- | Close a database connection. close :: Connection -> IO () -- | Opens a database connection, executes an action using this connection, -- and closes the connection, even in the presence of exceptions. withConnection :: String -> (Connection -> IO a) -> IO a -- | http://www.sqlite.org/c3ref/profile.html -- -- Enable/disable tracing of SQL execution. Tracing can be disabled by -- setting Nothing as the logger callback. -- -- Warning: If the logger callback throws an exception, your whole -- program may crash. Enable only for debugging! setTrace :: Connection -> Maybe (Text -> IO ()) -> IO () -- | Perform a SELECT or other SQL query that is expected to -- return results. All results are retrieved and converted before this -- function returns. -- -- When processing large results, this function will consume a lot of -- client-side memory. Consider using fold instead. -- -- Exceptions that may be thrown: -- -- query :: (ToRow q, FromRow r) => Connection -> Query -> q -> IO [r] -- | A version of query that does not perform query substitution. query_ :: FromRow r => Connection -> Query -> IO [r] -- | Returns the rowid of the most recent successful INSERT on the given -- database connection. -- -- See also http://www.sqlite.org/c3ref/last_insert_rowid.html. lastInsertRowId :: Connection -> IO Int64 -- | Execute an INSERT, UPDATE, or other SQL query that -- is not expected to return results. -- -- Throws FormatError if the query could not be formatted -- correctly. execute :: ToRow q => Connection -> Query -> q -> IO () -- | A version of execute that does not perform query substitution. execute_ :: Connection -> Query -> IO () field :: FromField a => RowParser a -- | Perform a SELECT or other SQL query that is expected to -- return results. Results are converted and fed into the action -- callback as they are being retrieved from the database. -- -- This allows gives the possibility of processing results in constant -- space (for instance writing them to disk). -- -- Exceptions that may be thrown: -- -- fold :: (FromRow row, ToRow params) => Connection -> Query -> params -> a -> (a -> row -> IO a) -> IO a -- | A version of fold which does not perform parameter -- substitution. fold_ :: FromRow row => Connection -> Query -> a -> (a -> row -> IO a) -> IO a -- | Opens a prepared statement. A prepared statement must always be closed -- with a corresponding call to closeStatement before closing the -- connection. Use nextRow to iterate on the values returned. Once -- nextRow returns Nothing, you need to invoke reset -- before reexecuting the statement again with nextRow. openStatement :: Connection -> Query -> IO Statement -- | Closes a prepared statement. closeStatement :: Statement -> IO () -- | Opens a prepared statement, executes an action using this statement, -- and closes the statement, even in the presence of exceptions. withStatement :: Connection -> Query -> (Statement -> IO a) -> IO a -- | Binds parameters to a prepared statement. Once nextRow returns -- Nothing, the statement must be reset with the reset -- function before it can be executed again by calling nextRow. bind :: ToRow params => Statement -> params -> IO () -- | Resets a statement. This does not reset bound parameters, if any, but -- allows the statement to be reexecuted again by invoking -- nextRow. reset :: Statement -> IO () -- | Return the name of a a particular column in the result set of a -- Statement. Throws an ArrayException if the colum index -- is out of bounds. -- -- http://www.sqlite.org/c3ref/column_name.html columnName :: Statement -> ColumnIndex -> IO Text -- | Binds parameters to a prepared statement, and resets the -- statement when the callback completes, even in the presence of -- exceptions. -- -- Use withBind to reuse prepared statements. Because it -- resets the statement after each usage, it avoids a -- pitfall involving implicit transactions. SQLite creates an implicit -- transaction if you don't say BEGIN explicitly, and does not -- commit it until all active statements are finished with either -- reset or closeStatement. withBind :: ToRow params => Statement -> params -> IO a -> IO a -- | Extracts the next row from the prepared statement. nextRow :: FromRow r => Statement -> IO (Maybe r) -- | Exception thrown if a Query was malformed. This may occur if -- the number of '?' characters in the query string does not -- match the number of parameters provided. data FormatError -- | Exception thrown if conversion from a SQL value to a Haskell value -- fails. data ResultError instance Typeable FormatError instance Eq ColumnIndex instance Ord ColumnIndex instance Enum ColumnIndex instance Num ColumnIndex instance Real ColumnIndex instance Integral ColumnIndex instance Eq FormatError instance Show FormatError instance Exception FormatError