The MultiCatalog Element

The MultiCatalog element defines a grouping of Express Server catalogs. It contains the following editable attributes:

name

This is the name of the multicatalog. The name is used to specify the multicatalog in requests through the Web API. If the name begins with a "." character (period or dot), then this multicatalog is "hidden." That is, it does not appear in the list of catalogs returned by Express Server. However, even though it is not included in that list, it is still loaded and available for queries when specified by name.

enabled

May be true or false, specifying whether the multicatalog is enabled or not. If set to false, then the multicatalog will not be loaded. The default value is true.

The MultiCatalog element can be treated in many ways like the Catalog element. It can contain any of the same elements that the Catalog element can contain except the SpatialIndex element. Specifically, these optional child elements are:

• BufferMergeRule
• Watermark
• SizeConstraint
• ThumbSpec
• Property

The SubCatalog Element

The SubCatalog element is a mandatory element of the MultiCatalog element. That is, there must be at least one subcatalog in a multicatalog. If there is only one, the multicatalog essentially acts as an alias, and you will have two identical catalogs with different names.

Like the Catalog element and the MultiCatalog element, the SubCatalog element must have a name attribute and defaults to enabled. The name attribute of the SubCatalog element must be the exact name of the catalog that you wish to incorporate as a subcatalog. Furthermore, the catalog being listed as a subcatalog:

• must be a valid catalog
• must have a spatial index
• must not be hidden

NOTE: Other multicatalogs can be included within the Subcatalog element.

Example: The MultiCatalog Element

<?xml version='1.0' encoding='utf-8' ?> 

<CatalogConfig>   

<MultiCatalog name="multi">

      <SubCatalog name="catalog1"/>      

<SubCatalog name="catalog2"/>

      <SubCatalog name="catalog3"/>   

</MultiCatalog>

</CatalogConfig>

NOTE: When you create or update an overview for a catalog that is part of a multicatalog, that multicatalog is unavailable until the overview is completed.