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: http://xmm.vilspa.esa.es/sas/8.0.0/doc/dal/node12.html
Дата изменения: Tue Jul 1 23:47:07 2008 Дата индексирования: Fri Sep 5 17:12:38 2008 Кодировка: Поисковые слова: comet hale-bopp |
Most objects in the Dal Model have a name, and an owner (usually referred to as the parent). This gives rise to an ancestral sequence of objects, beginning with the dataset and continuing to the object. The Qualified Name, of an object is the token-separated concatenation of names of each object in this sequence.
The colon character is used to separate the names of datasets, blocks and columns, but the % character is used before an attribute name.
e.g. "set:tab:col%att" is the fully qualified name of the column-attribute with name "att", whose parent column has name "col", whose parent table has name "tab", whose parent dataset has name "set".
It is possible to omit the block, column or attribute name from a qualified name. The effect of this is equivalent to specifying the name of the first block in a dataset, the first column in a table, or the first attribute in an attributable e.g.the qualified name "set::col" may be used to access the column with name "col" in the first table contained in the dataset with name "set".
The qualified name of an object may be passed to many of the functions and subroutines. The DAL will parse these names and raise an error if inconsistencies are detected.