Database.HaskellDB.Database

Defines standard database operations and the primitive hooks that a particular database binding must provide.

Operators

(!.) :: Select f r a => r -> f -> a infix 9

The (!.) operator selects over returned records from the database (= rows) Non-overloaded version of !. For backwards compatibility.

Type declarations

data Database

Constructors

Database

Fields

dbQuery :: forall er vr. GetRec er vr => PrimQuery -> Rel er -> IO [Record vr]

dbInsert :: TableName -> Assoc -> IO ()

dbInsertQuery :: TableName -> PrimQuery -> IO ()

dbDelete :: TableName -> [PrimExpr] -> IO ()

dbUpdate :: TableName -> [PrimExpr] -> Assoc -> IO ()

dbTables :: IO [TableName]

dbDescribe :: TableName -> IO [(Attribute, FieldDesc)]

dbTransaction :: forall a. IO a -> IO a

dbCreateDB :: String -> IO ()

dbCreateTable :: TableName -> [(Attribute, FieldDesc)] -> IO ()

dbDropDB :: String -> IO ()

dbDropTable :: TableName -> IO ()

dbCommit :: IO ()

class GetRec er vr | er -> vr, vr -> er where

Methods

getRec

Arguments

:: GetInstances s

Driver functions for getting values of different types.

-> Rel er

Phantom argument to the the return type right

-> Scheme

Fields to get.

-> s

Driver-specific result data (for example a Statement object)

-> IO (Record vr)

Result record.

Create a result record.

Instances

GetRec RecNil RecNil

(GetValue a, GetRec er vr) => GetRec (RecCons f (Expr a) er) (RecCons f a vr)

data GetInstances s

Functions for getting values of a given type. Database drivers need to implement these functions and pass this record to getRec when getting query results.

All these functions should return Nothing if the value is NULL.

Constructors

GetInstances

Fields

getString :: s -> String -> IO (Maybe String)

Get a String value.

getInt :: s -> String -> IO (Maybe Int)

Get an Int value.

getInteger :: s -> String -> IO (Maybe Integer)

Get an Integer value.

getDouble :: s -> String -> IO (Maybe Double)

Get a Double value.

getBool :: s -> String -> IO (Maybe Bool)

Get a Bool value.

getCalendarTime :: s -> String -> IO (Maybe CalendarTime)

Get a CalendarTime value.

getLocalTime :: s -> String -> IO (Maybe LocalTime)

Get a LocalTime value.

class GetValue a where

Methods

getValue :: GetInstances s -> s -> String -> IO a

Instances

GetValue Bool

GetValue Double

GetValue Int

GetValue Integer

GetValue String

GetValue CalendarTime

GetValue LocalTime

GetValue (Maybe Bool)

GetValue (Maybe Double)

GetValue (Maybe Int)

GetValue (Maybe Integer)

GetValue (Maybe String)

GetValue (Maybe CalendarTime)

GetValue (Maybe LocalTime)

Size n => GetValue (Maybe (BoundedString n))

Size n => GetValue (BoundedString n)

Function declarations

query :: GetRec er vr => Database -> Query (Rel er) -> IO [Record vr]

performs a query on a database

insert :: (ToPrimExprs r, ShowRecRow r, InsertRec r er) => Database -> Table er -> Record r -> IO ()

Inserts a record into a table

delete

Arguments

:: ShowRecRow r

=> Database

The database

-> Table r

The table to delete records from

-> (Rel r -> Expr Bool)

Predicate used to select records to delete

-> IO ()

deletes a bunch of records

update

Arguments

:: (ShowLabels s, ToPrimExprs s)

=> Database

The database

-> Table r

The table to update

-> (Rel r -> Expr Bool)

Predicate used to select records to update

-> (Rel r -> Record s)

Function used to modify selected records

-> IO ()

Updates records

insertQuery :: ShowRecRow r => Database -> Table r -> Query (Rel r) -> IO ()

Inserts values from a query into a table

tables

Arguments

:: Database

Database

-> IO [TableName]

Names of all tables in the database

List all tables in the database

describe

Arguments

:: Database

Database

-> TableName

Name of the tables whose columns are to be listed

-> IO [(Attribute, FieldDesc)]

Name and type info for each column

List all columns in a table, along with their types

transaction

Arguments

:: Database

Database

-> IO a

Action to run

-> IO a

Performs some database action in a transaction. If no exception is thrown, the changes are committed.

commit

Arguments

:: Database

Database

-> IO ()

Commit any pending data to the database.

createDB

Arguments

:: Database

Database

-> String

Name of database to create

-> IO ()

Is not very useful. You need to be root to use it. We suggest you solve this in another way

createTable

Arguments

:: Database

Database

-> TableName

Name of table to create

-> [(Attribute, FieldDesc)]

The fields of the table

-> IO ()

dropDB

Arguments

:: Database

Database

-> String

Name of database to drop

-> IO ()

dropTable

Arguments

:: Database

Database

-> TableName

Name of table to drop

-> IO ()