GNOME Data Access 3.0 manual

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Abstract

GNOME Data Access (GDA) is an architecture whose purpose is to provide universal access to many different kinds and types of data sources. This goes from traditional relational database systems, to any imaginable kind of data source such as a mail server, a LDAP directory...

This universality is obtained through the use of an easily extensible plug-in system as the mechanism for communication between the different components in the architecture.

I. Getting started

Introduction

libgda features

libgda architecture

Installation

Introduction

Installing

Debian installation

Compiling with the library

Configuring

Configuration for development
Configuration for accessing a database
Provider's specific information

Examples

Initialising

Connecting

Executing queries

Building commands
Making non queries
Making normal queries

Managing data models

Example using direct cell access
Example using row access
Freeing data models

Managing values

Managing transactions

Managing errors

Full example

Migration from older versions

GdaValue and GdaDataModel changes
GdaClient, GdaConnection and GdaError
Various API changes

Limitations

For MySQL

gda_server_provider_get_last_insert_id()

For Oracle

gda_server_provider_get_last_insert_id()

For PostgreSQL

BLOB handling
gda_server_provider_get_last_insert_id()

For SQLite

gda_server_provider_get_last_insert_id()

For Other providers

gda_server_provider_get_last_insert_id()

II. Client API Reference

Object Hierarchy

Initialization and configuration

Libgda initialization — Library initialization
Configuration — Access/Management of libgda configuration

Connections & commands

GdaClient — Database client access
GdaConnection — Management of connections to data sources
GdaConnectionEvent — Any event which has occurred on a GdaConnection
GdaTransactionStatus — Keeps track of the transactional status of a connection
Commands — Issuing commands to the provider
Convenient functions — Do quickly some actions

Data handling

Gda Value — Single value stored in a GdaDataModel
Blobs — Blobs handling
GdaParameter — Represents a GValue with various attributes
GdaParameterList — Manages a list of GdaParameter objects which contain individual values
GdaDataModel — Basic data model class
GdaDataModel columns — Management of GdaDataModel column attributes
GdaDataModelIter
GdaDataModelImport — Importing data from a string or a file
GdaDataAccessWrapper — Offers a random access on top of a cursor-only access data model
GdaDataModelArray — An implementation of GdaDataModel based on an array
GdaDataModelHash — An implementation of GdaDataModel based on a hash table
GdaDataModelQuery — An implementation of GdaDataModel based on a SELECT query
GdaDataModelFilterSQL — Filtering data from one or several GdaDataModel objects
GdaDataProxy — Proxy to hold modifications for any GdaDataModel, and provides the GdaDataModel interface itself
GdaDataModelIndex — Management of GdaDataModel indexes
GdaDataModel column indexes — Management of GdaDataModel column index attributes

Data conversions

GdaDataHandler — Interface which provides data handling capabilities
GdaHandlerString — Default handler for strings
GdaHandlerBoolean — Default handler for booleans
GdaHandlerTime — Default handler for time, date and timestamp
GdaHandlerNumerical — Default handler for numeric values
GdaHandlerBin — Default handler for binary values
GdaHandlerType — Default handler for GType values

Dictionary and related objects

GdaDict — GDA dictionary
GdaDictType — Represents a data type in the DBMS
GdaDictFunction — Represents a function in the DBMS.
GdaDictAggregate — Represents an aggregate in the DBMS (like COUNT() or AVG() for example)
GdaDictDatabase — Represents a database structure in the DBMS server
GdaDictTable — Represents a table or a view in the database
GdaDictField — Represents a field in a table or a view in the database
GdaDictConstraint — Represents a constraint within a database
GdaDictExtend — Make GdaDict manage other types of objects

Data manipulation (DML) queries

GdaQuery — Represents any kind of DML query
GdaQueryTarget — Represents a target entity within a query.
GdaQueryJoin — Represents a join between two different entities
GdaQueryFieldAll — Represents all the fields of an entity (through a GdaQueryTarget object)
GdaQueryFieldField — Represents one field of an entity (through a GdaQueryTarget object)
GdaQueryFieldFunc — Represents a function (selected by a GdaDictFunction object)
GdaQueryFieldAgg — Represents a function (selected by a GdaDictAggregate object)
GdaQueryFieldValue — Represents a single value (or a parameter)
GdaQueryCondition — Represents a condition within a query

Data definition (DDL) queries

GdaServerOperation — Handles any DDL query in an abstract way

Miscellaneous

Utility functions
Logging — Log functions
Quark lists — Quark lists (lists of KEY=VALUE's)
GdaObject — The base class for many of the library's objects
GdaObjectRef — Used to reference other objects
GdaGraphviz — Creates .dot files which can then be processed with GraphViz.
GdaDataModelRow — Base implementation for other objects to implement the GdaDataModel interface based on the usage of
GdaQueryField — Parent class for any query's field
GdaQueryObject — Parent class for any object participating in a GdaQuery query
GdaThreader

Graphs

GdaGraph — Data model to keep graphs' layout
GdaGraphQuery — A graph specialized in displaying query components
GdaGraphItem — Parts of data model used with the GdaGraph object.

List of lesser used interfaces

GdaEntity — Interface to represent a generic entity (for tables, views or queries)
GdaEntityField — Interface to represent a generic field (for tables's fields, etc).
GdaXmlStorage — Interface which provides saving and loading using XML structures
GdaRenderer — Interface to get representations of objects as SQL statements, XML nodes or human readable text
GdaReferer — Interface to know when on object is completely defined

III. GDA Tools