This interface is used to interact with the distributed database. More...

#include <idatabase.h>

Inheritance diagram for mi::neuraylib::IDatabase:

Public Types
enum	Garbage_collection_priority { PRIORITY_LOW = 0 , PRIORITY_MEDIUM = 1 , PRIORITY_HIGH = 2 , PRIORITY_FORCE_32_BIT = 0xffffffffU }
	Priorities for synchronous garbage collection runs. More...

Public Types inherited from mi::base::Interface_declare< 0x814ae637, ... >
typedef Interface_declare< id1, ... >	Self
	Own type. More...

typedef Uuid_t< id1, ... >	IID
	Declares the interface ID (IID) of this interface. More...

Public Types inherited from mi::base::IInterface
typedef Uuid_t<0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0>	IID
	Declares the interface ID (IID) of this interface. More...

Public Member Functions
virtual IScope *	get_global_scope () const =0
	Returns the global scope which is the root of a tree of scopes. More...

virtual IScope *	create_scope (IScope *parent, Uint8 privacy_level=0, bool temp=false)=0
	Creates a new optionally temporary scope at the given privacy level with the given parent scope ID. More...

virtual IScope *	get_scope (const char *id) const =0
	Looks up and returns a scope with a given ID. More...

virtual Sint32	remove_scope (const char *id) const =0
	Removes a scope with the specified ID. More...

virtual void	lock (Uint32 lock_id)=0
	Acquires a DB lock. More...

virtual Sint32	unlock (Uint32 lock_id)=0
	Releases a previously obtained DB lock. More...

virtual IScope *	create_or_get_named_scope (const char name, IScope parent=0, Uint8 privacy_level=0)=0
	Creates or retrieves a new named scope at the given privacy level with the given parent scope ID. More...

virtual IScope *	get_named_scope (const char *name) const =0
	Looks up and returns a scope with a given name. More...

virtual void	garbage_collection (Garbage_collection_priority priority=PRIORITY_MEDIUM)=0
	Triggers a synchronous garbage collection run. More...

Public Member Functions inherited from mi::base::IInterface
virtual Uint32	retain () const =0
	Increments the reference count. More...

virtual Uint32	release () const =0
	Decrements the reference count. More...

virtual const IInterface *	get_interface (const Uuid &interface_id) const =0
	Acquires a const interface from another. More...

template<class T>
const T *	get_interface () const
	Acquires a const interface from another. More...

virtual IInterface *	get_interface (const Uuid &interface_id)=0
	Acquires a mutable interface from another. More...

template<class T>
T *	get_interface ()
	Acquires a mutable interface from another. More...

virtual Uuid	get_iid () const =0
	Returns the interface ID of the most derived interface. More...

Additional Inherited Members
Static Public Member Functions inherited from mi::base::Interface_declare< 0x814ae637, ... >
static bool	compare_iid (const Uuid &iid)
	Compares the interface ID `iid` against the interface ID of this interface and of its ancestors. More...

Static Public Member Functions inherited from mi::base::IInterface
static bool	compare_iid (const Uuid &iid)
	Compares the interface ID `iid` against the interface ID of this interface. More...

Detailed Description

This interface is used to interact with the distributed database.

Member Enumeration Documentation

^◆ Garbage_collection_priority

enum mi::neuraylib::IDatabase::Garbage_collection_priority

Priorities for synchronous garbage collection runs.

Enumerator

PRIORITY_LOW

Low priority for synchronous garbage collection runs.

Use this priority if the performance of other concurrent DB operations is more important than a fast synchronous garbage collection.

PRIORITY_MEDIUM

Medium priority for synchronous garbage collection runs.

This priority attempts to maintain a balance between the synchronous garbage collection and other concurrent DB operations.

PRIORITY_HIGH

High priority for synchronous garbage collection runs.

Other concurrent DB operations will experience a large performance drop. Therefore, this priority should not be used in multi-user settings.

Member Function Documentation

^◆ create_or_get_named_scope()

virtual IScope * mi::neuraylib::IDatabase::create_or_get_named_scope	(	const char *	name,
		IScope *	parent = `0`,
		Uint8	privacy_level = `0`
	)

pure virtual

Creates or retrieves a new named scope at the given privacy level with the given parent scope ID.

Parameters

name	A name which can be used to lookup the scope. If a scope with the same name exists already then it will be returned if the parent and privacy level are identical. Otherwise creating the scope will fail.
parent	The parent scope for this scope. If the value is `NULL` the created scope will be a child of the global scope.
privacy_level	The privacy level of the scope. This must be higher than the privacy level of the parent scope. The privacy level of the global scope is 0 (and the global scope is the only scope with privacy level 0). The default value of 0 indicates the privacy level of the parent scope plus 1.

Returns: The created scope or NULL if something went wrong.

^◆ create_scope()

virtual IScope * mi::neuraylib::IDatabase::create_scope	(	IScope *	parent,
		Uint8	privacy_level = `0`,
		bool	temp = `false`
	)

pure virtual

Creates a new optionally temporary scope at the given privacy level with the given parent scope ID.

Note: A scope continues to exist if the pointer returned by this method is released. Use remove_scope() to remove a scope.

Parameters

parent	The parent scope for this scope. If the value is `NULL` the created scope will be a child of the global scope.
privacy_level	The privacy level of the scope. This must be higher than the privacy level of the parent scope. The privacy level of the global scope is 0 (and the global scope is the only scope with privacy level 0). The default value of 0 indicates the privacy level of the parent scope plus 1.
temp	A bool indicating if the scope is temporary. If the scope is temporary, then when the host that created the scope is removed from the cluster the scope and all data contained in the scope will be removed. If the scope is not temporary, the default, then when the creating host is removed from the cluster the scope and all contained data will remain in the database.

Returns: The created scope or NULL if something went wrong.

^◆ garbage_collection()

virtual void mi::neuraylib::IDatabase::garbage_collection ( Garbage_collection_priority priority = PRIORITY_MEDIUM )

pure virtual

Triggers a synchronous garbage collection run.

The method sweeps through the entire database and removes all database elements which have been marked for removal and are no longer referenced. Note that it is not possible to remove database elements if there are open transactions in which such an element is still referenced.

To mark an element for removal use mi::neuraylib::IDice_transaction::remove() or mi::neuraylib::IDice_transaction::store_for_reference_counting().

Parameters

priority The intended priority of the synchronous garbage collection run.

^◆ get_global_scope()

virtual IScope * mi::neuraylib::IDatabase::get_global_scope ( ) const

pure virtual

Returns the global scope which is the root of a tree of scopes.

Returns: The global scope which is guaranteed to exist after startup of the system.

^◆ get_named_scope()

virtual IScope * mi::neuraylib::IDatabase::get_named_scope ( const char * name ) const

pure virtual

Looks up and returns a scope with a given name.

Parameters

name	The name of the scope

Returns: The found scope or NULL if no such scope exists.

^◆ get_scope()

virtual IScope * mi::neuraylib::IDatabase::get_scope ( const char * id ) const

pure virtual

Looks up and returns a scope with a given ID.

Parameters

id	The ID of the scope as returned by mi::neuraylib::IScope::get_id().

Returns: The found scope or NULL if no such scope exists.

^◆ lock()

virtual void mi::neuraylib::IDatabase::lock ( Uint32 lock_id )

pure virtual

Acquires a DB lock.

The method blocks until the requested lock has been obtained. Recursively locking the same lock from within the same thread on the same host is supported.

If the host holding a lock leaves the cluster, the lock is automatically released.

Parameters

lock_id The lock to acquire.

Note: The locking mechanism is kind of a co-operative locking mechanism: The lock does not prevent other threads from accessing or editing the DB. It only prevents other threads from obtaining the same lock.; DB locks are not restricted to threads on a single host, they apply to all threads on all hosts in the cluster.; DB locks are an expensive operation and should only be used when absolutely necessary.

^◆ remove_scope()

virtual Sint32 mi::neuraylib::IDatabase::remove_scope ( const char * id ) const

pure virtual

Removes a scope with the specified ID.

Note that scopes are reference counted. The actual removal will not happen before all elements referencing the scope have been released, e.g., child scopes, transactions, database elements, including handles to the scope itself. Even when all these conditions are met, scope removal might actually happen at a later point in time, depending on the timing of past and current transactions, even in unrelated scopes.

It is not possible to remove the global scope.

Parameters

id	The ID of the scope as returned by mi::neuraylib::IScope::get_id().

Returns: 0, in case of success, -1 in case of failure.

^◆ unlock()

virtual Sint32 mi::neuraylib::IDatabase::unlock ( Uint32 lock_id )

pure virtual

Releases a previously obtained DB lock.

If the lock has been locked several times from within the same thread on the same host, it simply decrements the lock count. If the lock count reaches zero, the lock is released.

Parameters

lock_id The lock to release.

Returns: 0, in case of success, -1 in case of failure, i.e, the lock is not held by this thread on this host

Public Types

Public Member Functions

Additional Inherited Members

Detailed Description

Member Enumeration Documentation

◆ Garbage_collection_priority

Member Function Documentation

◆ create_or_get_named_scope()

◆ create_scope()

◆ garbage_collection()

◆ get_global_scope()

◆ get_named_scope()

◆ get_scope()

◆ lock()

◆ remove_scope()

◆ unlock()

^◆ Garbage_collection_priority

^◆ create_or_get_named_scope()

^◆ create_scope()

^◆ garbage_collection()

^◆ get_global_scope()

^◆ get_named_scope()

^◆ get_scope()

^◆ lock()

^◆ remove_scope()

^◆ unlock()