Model Tree Structures with an Array of Ancestors Array of Ancestors模式同样将每个节点存储在一个单独的document中。另外每个节点document中还有一个数组用于存储节点的祖先ID或路径。除了祖先外,另外还有一个字段存储节点直接父亲节点的ID引用,示例图的Arrar of Ancestors模式存储方式如下: db.categories.insert( { _...
Tree Navigation The node with the large border is the reference node (the node from which the navigation method is invoked.) The yellow nodes are those returned by the method. parentroot1ancestors nil for a root nodeself for a root noderoot..parent ...
祖先数组 模式为需要在树结构里查找某个子树节点以及某个节点的所有祖先节点的场景提供了一个快速有效的方案。对于经常需要操作子树的场景,这是个很好的选择。 The Array of Ancestors pattern is slightly slower than the Materialized Paths pattern but is more straightforward to use.←...
(or hierarchy). It uses a single, intuitively formatted database column, using a variation on the materialised path pattern. It exposes all the standard tree structure relations (ancestors, parent, root, children, siblings, descendants) and all of them can be fetched in a single SQL query. ...
However, when you use this method on new tree node objects, additional functionality is added to make sure the tree structure stays consistent. When you call it on an object and you have used one of the collection methods documented below, the new object is inserted in the tree relative to...
Most basic structure of model tree. This is an abstract class that is a base for other classes representing different nodes in model. Note: If a node is detached from the model tree, you can manipulate it using it's API. However, it is very important that nodes already attached to ...
Fission yeasts are a small clade at the base of the Ascomycete phylogenetic tree with overall conservation of gene content and gene structure between the four species [95].S. japonicusforms an early diverging branch within the clade. Strikingly,S. pombe, a widely used model organism, undergoes ...
This can be used to ensure that the DOM view of a document is the same as if it were saved and re-loaded, and is useful when operations (such as XPointer lookups) that depend on a particular document tree structure are to be used. ...
An organism’s genome consists of several types of loci that are known to perform diverse functions: these functional loci include genes, gene regulatory regions, and sequences maintaining chromosome structure [1]. However, measuring the proportions of the functional parts of genomes is a subject ...
In contrary to nodes, which are building blocks of the model document tree, markers are not stored directly in the document tree but in the model markers' collection. Still, they are document data, by giving additional meaning to the part of a model document between marker start and marker ...