Gnome::Gda::MetaStore Class Reference

Dictionary object. More...

Inherits Glib::Object.

Collaboration diagram for Gnome::Gda::MetaStore:
Collaboration graph
[legend]

List of all members.

Public Member Functions

virtual ~MetaStore ()
GdaMetaStore* gobj ()
 Provides access to the underlying C GObject.
const GdaMetaStore* gobj () const
 Provides access to the underlying C GObject.
GdaMetaStore* gobj_copy ()
 Provides access to the underlying C instance. The caller is responsible for unrefing it. Use when directly setting fields in structs.
int get_version () const
 Get store's internal schema's version.
Glib::RefPtr< DataModelextract (const Glib::ustring& sql)
 Extracts some data stored in store using a custom SELECT query.
bool modify (const Glib::ustring& sql, const Glib::RefPtr< DataModel >& data_model, const Glib::ustring& condition)
 Propagates an update to store, the update's contents is represented by new_data, this function is primarily reserved to database providers.
bool modify_with_context (MetaContext* context, const Glib::RefPtr< DataModel >& new_data)
 Propagates an update to store, the update's contents is represented by new_data, this function is primarily reserved to database providers.
Glib::RefPtr< DataModelcreate_modify_data_model (const Glib::ustring& table_name)
 Creates a new Gda::DataModelArray data model which can be used, after being correctly filled, with the gda_meta_store_modify*() methods.
Glib::RefPtr< MetaStructschema_get_structure ()
 Creates a new Gda::MetaStruct object representing store's interal database structure.
Glib::SListHandle< Glib::ustringschema_get_all_tables ()
 Get an ordered list of the tables store knows about.
Glib::SListHandle< Glib::ustringschema_get_depend_tables (const Glib::ustring& table_name)
 Get an ordered list of the tables store knows about on which the table_name table depends (recursively).
bool get_attribute_value (const Glib::ustring& att_name, Glib::ustring& att_value)
 The Gda::MetaStore object maintains a list of (name,value) attributes (attributes names starting with a '_' character are for internal use only and cannot be altered).
bool set_attribute_value (const Glib::ustring& att_name, const Glib::ustring& att_value)
 Set the value of the attribute named att_name to att_value; see get_attribute_value() for more information.
bool schema_add_custom_object (const Glib::ustring& xml_description)
 The internal database used by store can be 'augmented' with some user-defined database objects (such as tables or views).
bool schema_remove_custom_object (const Glib::ustring& obj_name)
 Removes the custom database object named obj_name.
Glib::RefPtr< Connectionget_internal_connection ()
 Get a pointer to the Gda::Connection object internally used by store to store its contents.
Glib::RefPtr< const Connectionget_internal_connection () const
 Get a pointer to the Gda::Connection object internally used by store to store its contents.
Glib::PropertyProxy_ReadOnly
< Glib::RefPtr< Connection > > 
property_cnc () const
 Connection object internally used.
Glib::SignalProxy0< void > signal_meta_reset ()

Static Public Member Functions

static Glib::RefPtr< MetaStorecreate (const Glib::ustring& cnc_string)

Protected Member Functions

 MetaStore (const Glib::ustring& cnc_string)
virtual void on_meta_reset ()

Related Functions

(Note that these are not member functions.)



Glib::RefPtr
< Gnome::Gda::MetaStore
wrap (GdaMetaStore* object, bool take_copy=false)
 A Glib::wrap() method for this object.

Detailed Description

Dictionary object.

Previous versions of Libgda relied on an XML based file to store dictionary information, such as the database's schema (tables, views, etc) and various other information. The problems were that it was difficult for an application to integrate its own data into the dictionary and that there were some performances problems as the XML file needed to be parsed (and converted into its own in-memory structure) before any data could be read out of it.

The new dictionary now relies on a database structure to store its data (see the database schema section for a detailled description). The actual database can be a single file (using an SQLite database), an entirely in memory database (also using an SQLite database), or a more conventional backend such as a PostgreSQL database for a shared dictionary on a server.


Constructor & Destructor Documentation

virtual Gnome::Gda::MetaStore::~MetaStore (  )  [virtual]
Gnome::Gda::MetaStore::MetaStore ( const Glib::ustring cnc_string  )  [explicit, protected]

Member Function Documentation

static Glib::RefPtr<MetaStore> Gnome::Gda::MetaStore::create ( const Glib::ustring cnc_string  )  [static]
Glib::RefPtr<DataModel> Gnome::Gda::MetaStore::create_modify_data_model ( const Glib::ustring table_name  ) 

Creates a new Gda::DataModelArray data model which can be used, after being correctly filled, with the gda_meta_store_modify*() methods.

*

To be used by provider's implementation

Parameters:
table_name The name of a table present in store.
Returns:
A new Gda::DataModel.
Glib::RefPtr<DataModel> Gnome::Gda::MetaStore::extract ( const Glib::ustring sql  ) 

Extracts some data stored in store using a custom SELECT query.

Parameters:
select_sql A SELECT statement.
Varargs A list of (variable name (gchar *), GValue *value) terminated with 0, representing values for all the variables mentionned in select_sql. If there is no variable then this part can be omitted.
Returns:
A new Gda::DataModel, or 0 if an error occurred.
bool Gnome::Gda::MetaStore::get_attribute_value ( const Glib::ustring att_name,
Glib::ustring att_value 
)

The Gda::MetaStore object maintains a list of (name,value) attributes (attributes names starting with a '_' character are for internal use only and cannot be altered).

This method and the set_attribute_value() method allows the user to add, set or remove attributes specific to their usage.

This method allows to get the value of a attribute stored in store. The returned attribute value is placed at att_value, the caller is responsible to free that string.

If there is no attribute named att_name then att_value is set to 0 and error will contain the GDA_META_STORE_ATTRIBUTE_NOT_FOUND_ERROR error code, and false is returned.

Parameters:
att_name Name of the attribute to get.
att_value The place to store the attribute value.
Returns:
true if no error occurred.
Glib::RefPtr<const Connection> Gnome::Gda::MetaStore::get_internal_connection (  )  const

Get a pointer to the Gda::Connection object internally used by store to store its contents.

The returned connection can be used to access some other data than the one managed by store itself. The returned object is not owned by the caller (if you need to keep it, then use Glib::object_ref()). Do not close the connection.

Returns:
A Gda::Connection, or 0.
Glib::RefPtr<Connection> Gnome::Gda::MetaStore::get_internal_connection (  ) 

Get a pointer to the Gda::Connection object internally used by store to store its contents.

The returned connection can be used to access some other data than the one managed by store itself. The returned object is not owned by the caller (if you need to keep it, then use Glib::object_ref()). Do not close the connection.

Returns:
A Gda::Connection, or 0.
int Gnome::Gda::MetaStore::get_version (  )  const

Get store's internal schema's version.

Retunrs: the version (1 at the moment)

const GdaMetaStore* Gnome::Gda::MetaStore::gobj (  )  const [inline]

Provides access to the underlying C GObject.

Reimplemented from Glib::ObjectBase.

GdaMetaStore* Gnome::Gda::MetaStore::gobj (  )  [inline]

Provides access to the underlying C GObject.

Reimplemented from Glib::ObjectBase.

GdaMetaStore* Gnome::Gda::MetaStore::gobj_copy (  ) 

Provides access to the underlying C instance. The caller is responsible for unrefing it. Use when directly setting fields in structs.

bool Gnome::Gda::MetaStore::modify ( const Glib::ustring sql,
const Glib::RefPtr< DataModel >&  data_model,
const Glib::ustring condition 
)

Propagates an update to store, the update's contents is represented by new_data, this function is primarily reserved to database providers.

For example tell store to update its list of tables, new_data should contain the same columns as the "_tables" table of store, and contain one row per table in the store; there should not be any more argument after the error argument.

Now, to update only one table, the new_data data model should have one row for the table to update (or no row at all if the table does not exist anymore), and have values for the promary key of the "_tables" table of store, namely "table_catalog", "table_schema" and "table_name".

Parameters:
table_name The name of the table to modify within store.
new_data A Gda::DataModel containing the new data to set in table_name, or 0 (treated as a data model with no row at all).
condition SQL expression (which may contain variables) defining the rows which are being obsoleted by new_data, or 0.
Varargs A list of (variable name (gchar *), GValue *value) terminated with 0, representing values for all the variables mentionned in condition.
Returns:
true if no error occurred.
bool Gnome::Gda::MetaStore::modify_with_context ( MetaContext *  context,
const Glib::RefPtr< DataModel >&  new_data 
)

Propagates an update to store, the update's contents is represented by new_data, this function is primarily reserved to database providers.

Parameters:
context A Gda::MetaContext context describing what to modify in store.
new_data A Gda::DataModel containing the new data to set in table_name, or 0 (treated as a data model with no row at all).
Returns:
true if no error occurred.
virtual void Gnome::Gda::MetaStore::on_meta_reset (  )  [protected, virtual]
Glib::PropertyProxy_ReadOnly< Glib::RefPtr<Connection> > Gnome::Gda::MetaStore::property_cnc (  )  const

Connection object internally used.

You rarely need to use properties because there are get_ and set_ methods for almost all of them.

Returns:
A PropertyProxy that allows you to get or set the property of the value, or receive notification when the value of the property changes.
bool Gnome::Gda::MetaStore::schema_add_custom_object ( const Glib::ustring xml_description  ) 

The internal database used by store can be 'augmented' with some user-defined database objects (such as tables or views).

This method allows one to add a new database object.

If the internal database already contains the object, then: <itemizedlist> <listitem>if the object is equal to the provided description then true is returned</listitem> <listitem>if the object exists but differs from the provided description, then false is returned, with the GDA_META_STORE_SCHEMA_OBJECT_CONFLICT_ERROR error code</listitem> </itemizedlist>

The xml_description defines the table of view's definition, for example: <![CDATA[<table name="mytable"> <column name="id" pkey="<tt>true</tt>"/> <column name="value"/> </table>]]>

The partial DTD for this XML description of the object to add is the following (the top node must be a <table> or a <view>): <![CDATA[<!ELEMENT table (column*,check*,fkey*,unique*)> <!ATTLIST table name NMTOKEN R::EQUIRED>

<!ELEMENT column EMPTY> <!ATTLIST column name NMTOKEN R::EQUIRED type CDATA I::MPLIED pkey (true|false) I::MPLIED autoinc (true|false) I::MPLIED nullok (true|false) I::MPLIED>

<!ELEMENT check (P::CDATA)>

<!ELEMENT fkey (part+)> <!ATTLIST fkey ref_table NMTOKEN R::EQUIRED>

<!ELEMENT part EMPTY> <!ATTLIST part column NMTOKEN I::MPLIED ref_column NMTOKEN I::MPLIED>

<!ELEMENT unique (column*)>

<!ELEMENT view (definition)> <!ATTLIST view name NMTOKEN R::EQUIRED descr CDATA I::MPLIED>

<!ELEMENT definition (P::CDATA)>]]>

Parameters:
xml_description An XML description of the table or view to add to store.
Returns:
true if the new object has sucessfully been added.
Glib::SListHandle<Glib::ustring> Gnome::Gda::MetaStore::schema_get_all_tables (  ) 

Get an ordered list of the tables store knows about.

The tables are ordered in a way that tables dependencies are respected: if table B has a foreign key on table A, then table A will be listed before table B in the returned list.

Returns:
A new list of tables names (as gchar*), the list must be freed when no longer needed, but the strings present in the list must not be modified.
Glib::SListHandle<Glib::ustring> Gnome::Gda::MetaStore::schema_get_depend_tables ( const Glib::ustring table_name  ) 

Get an ordered list of the tables store knows about on which the table_name table depends (recursively).

The tables are ordered in a way that tables dependencies are respected: if table B has a foreign key on table A, then table A will be listed before table B in the returned list.

Parameters:
table_name The name of the table for which all the dependencies must be listed.
Returns:
A new list of tables names (as gchar*), the list must be freed when no longer needed, but the strings present in the list must not be modified.
Glib::RefPtr<MetaStruct> Gnome::Gda::MetaStore::schema_get_structure (  ) 

Creates a new Gda::MetaStruct object representing store's interal database structure.

Returns:
A new Gda::MetaStruct object, or 0 if an error occurred.
bool Gnome::Gda::MetaStore::schema_remove_custom_object ( const Glib::ustring obj_name  ) 

Removes the custom database object named obj_name.

Parameters:
obj_name Name of the custom object to remove.
Returns:
true if the custom object has sucessfully been removed.
bool Gnome::Gda::MetaStore::set_attribute_value ( const Glib::ustring att_name,
const Glib::ustring att_value 
)

Set the value of the attribute named att_name to att_value; see get_attribute_value() for more information.

Parameters:
att_name Name of the attribute to set.
att_value Value of the attribute to set, or 0 to unset the attribute.
Returns:
true if no error occurred.
Glib::SignalProxy0< void > Gnome::Gda::MetaStore::signal_meta_reset (  ) 
Prototype:
void on_my_meta_reset()

Friends And Related Function Documentation

Glib::RefPtr< Gnome::Gda::MetaStore > wrap ( GdaMetaStore *  object,
bool  take_copy = false 
) [related]

A Glib::wrap() method for this object.

Parameters:
object The C instance.
take_copy False if the result should take ownership of the C instance. True if it should take a new copy or ref.
Returns:
A C++ instance that wraps this C instance.

The documentation for this class was generated from the following file:

Generated on Fri Aug 6 18:07:46 2010 for libgdamm by  doxygen 1.6.1