class: Relation

[34:7] extends: object

A GRelation is a table of data which can be indexed on any number of fields, rather like simple database tables. A GRelation contains a number of records, called tuples. Each record contains a number of fields. Records are not ordered, so it is not possible to find the record at a particular index. Note that GRelation tables are currently limited to 2 fields. To create a GRelation, use [func@GLib.Relation.new]. To specify which fields should be indexed, use [method@GLib.Relation.index]. Note that this must be called before any tuples are added to the GRelation. To add records to a GRelation use [method@GLib.Relation.insert]. To determine if a given record appears in a GRelation, use [method@GLib.Relation.exists]. Note that fields are compared directly, so pointers must point to the exact same position (i.e. different copies of the same string will not match.) To count the number of records which have a particular value in a given field, use [method@GLib.Relation.count]. To get all the records which have a particular value in a given field, use [method@GLib.Relation.select]. To access fields of the resulting records, use [method@GLib.Tuples.index]. To free the resulting records use [method@GLib.Tuples.destroy]. To delete all records which have a particular value in a given field, use [method@GLib.Relation.delete]. To destroy the GRelation, use [method@GLib.Relation.destroy]. To help debug GRelation objects, use [method@GLib.Relation.print]. GRelation has been marked as deprecated, since this API has never been fully implemented, is not very actively maintained and rarely used.

Members

• handleObj
• lib
• retainedCallbacks
• signalHandlerNames
• signalSetterHandlers

Methods

• Relation (Handle = null)

  Creates a new Relation by wrapping a native handle or another wrapper.

  • @p Handle is the native handle or another wrapper whose handle to adopt.

• toNativeHandle (Source)

  Normalizes a constructor argument into a raw pointer carrier. Accepts a raw NativeHandle, a raw NativeBuffer returned from fn.call(...), another generated wrapper exposing handle(), or null. Returns null when the argument carries no pointer.

  • @p Source is the raw handle, raw buffer, wrapper, or null.
  • @r A raw pointer carrier or null when no pointer is present.

• getLib ()

  Returns the opened native library for this generated wrapper.

  • @r The opened native library.

• handle ()

  Returns the wrapped NativeHandle.

  • @r The wrapped NativeHandle.

• isNull ()

  Returns true when the wrapped handle is null.

  • @r A bool.

• describe ()

  Returns a small string for debugging generated wrappers.

  • @r A string.