Database.HsSqlPpp.Catalog

Contents

Description

This module contains the database catalog data types and helper functions.

The catalog data type serves the following purposes:

Contains all the catalog information needed to type check against an existing database.
A copy of the catalog information from a default template1 database is included - defaultTemplate1Catalog.
It is used internally to keep track of updates to the catalog whilst running an annotation process (e.g. so that a select can type check against a create table given in the same source). It is also used to track other identifier types, such as attribute references in select expressions, and argument and variable types inside create function statements.

You can see what kind of stuff is contained in the Catalog type by looking at the CatalogUpdate type.

Synopsis

Data types

data Catalog

The main datatype, this holds the catalog and context information to type check against.

Updates

data CatalogUpdate

Constructors

CatCreateScalar Type String Bool	add a new scalar type with the name given, also creates an array type automatically
CatCreateDomain Type Type	add a new domain to the catalog
CatCreateComposite String [(String, Type)]	add a new composite type to the catalog
CatCreateCast Type Type CastContext	add a new cast to the catalog
CatCreateTable String [(String, Type)] [(String, Type)]	add a new table to the catalog with the given public and private columns also creates the composite type to go with this table
CatCreateView String [(String, Type)]	add the view to the catalog, using the column names and types supplied
CatCreateFunction FunFlav String [Type] Type Bool	add a new function to the catalog
CatDropFunction Bool String [Type]	drop a function from the catalog

ppCatUpdate :: CatalogUpdate -> String

attempt to show a readable representation of a CatalogUpdate value

bits and pieces

data CastContext

Use to note what the flavour of a cast is, i.e. if/when it can be used implicitly.

Constructors

ImplicitCastContext
AssignmentCastContext
ExplicitCastContext

data CompositeFlavour

Used to distinguish between standalone composite types, and automatically generated ones, generated from a table or view respectively.

Constructors

Composite
TableComposite
ViewComposite

type CompositeDef = (String, CompositeFlavour, Type, Type)

Provides the definition of a composite type. The components are composite (or table or view) name, the flavour of the composite, the types of the composite attributes, and the types of the system columns iff the composite represents a table type (the third and fourth components are always CompositeTypes).

type FunctionPrototype = (String, [Type], Type, Bool)

The components are: function (or operator) name, argument types, return type and is variadic.

type DomainDefinition = (Type, Type)

The components are domain type, base type (todo: add check constraint).

data FunFlav

Constructors

FunPrefix
FunPostfix
FunBinary
FunName
FunAgg
FunWindow

Catalog values

emptyCatalog :: Catalog

Represents an empty catalog. This doesn't contain things like the 'and' operator, defaultCatalog contains these.

defaultCatalog :: Catalog

Represents what you probably want to use as a starting point if you are building an catalog from scratch. It contains information on built in function like things that aren't in the PostgreSQL catalog, such as greatest, coalesce, keyword operators like 'and', etc..

defaultTemplate1Catalog :: Catalog