mysql-simple-0.2.0.0: A mid-level MySQL client library.

Portabilityportable
Stabilityexperimental
MaintainerBryan O'Sullivan <bos@mailrank.com>

Database.MySQL.Simple.Types

Description

Basic types.

Synopsis

Documentation

data Null Source

A placeholder for the SQL NULL value.

Constructors

Null 

newtype Only a Source

A single-value collection.

This can be handy if you need to supply a single parameter to a SQL query.

Example:

query "select x from scores where x > ?" (Only (42::Int))

Constructors

Only 

Fields

fromOnly :: a
 

Instances

Functor Only 
Typeable1 Only 
Eq a => Eq (Only a) 
Ord a => Ord (Only a) 
Read a => Read (Only a) 
Show a => Show (Only a) 
Result a => QueryResults (Only a) 
Param a => QueryParams (Only a) 

newtype In a Source

Wrap a list of values for use in an IN clause. Replaces a single "?" character with a parenthesized list of rendered values.

Example:

 query "select * from whatever where id in ?" (In [3,4,5])

Constructors

In a 

Instances

Functor In 
Typeable1 In 
Eq a => Eq (In a) 
Ord a => Ord (In a) 
Read a => Read (In a) 
Show a => Show (In a) 
Param a => Param (In [a]) 

newtype Query Source

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.MySQL.Simple

 q :: Query
 q = "select ?"

Constructors

Query