F

facet

MarkLogic. A constraint used for navigation on search results, providing a set of values that exist matching documents. Facets usually include a count of the resulting number of distinct values. Facets returned by a search include the counts and values needed to generate the user interface for the results. For example, a data set of articles could provide facets on author and publication date.

faceted navigation

MarkLogic. A type of navigation in the user interface that makes use of facets. With faceted navigation, a user can access focused search results by narrowing the search criteria through the use of facets.

failover - local disk

MarkLogic. Local-Disk Failover uses the intra-cluster forest replication capability introduced with MarkLogic 4.2. With forest replication you can have all writes to one forest be automatically replicated to another forest or set of forests, with each forest held on a different set of disks, generally cheap local disks, for redundancy.

failover - shared disk

MarkLogic. Shared-Disk Failover uses a clustered filesystem, such as Veritas or GFS. Every Data Manager stores its forest data on a SAN that's potentially accessible by other servers in the cluster. Should one D-node server fail, it will be removed from the cluster and another server in the cluster with access to the SAN will take over for each of its forests.

fast failover

MarkLogic. If one or more host forests are configured for local-disk or shared-disk failover, you now have the option to failover those forests when you shut down the host. A new option, Immediately fail over forests to replica hosts, has been added to the Host Shutdown confirmation page to enable you to fail over the forests to replica hosts

field

MarkLogic. A field is typically a small subset of the whole database, a portion of the content that you might want to query as a single unit, such as an abstract. Fields have their own set of indexes, independent of the database indexes. Because the field represents only a relatively small percentage of the content, the relative cost of the extra indexing is small. See Overview of Fields in Administrate MarkLogic Server.

filtered search

Search. A filtered search is one that is configured to include a filtering step that checks whether each candidate result matches the search criteria. Candidates that do meet the criteria are discarded. A filtered search is accurate, but takes longer than an equivalent unfiltered search. For details, see Understanding the Search Process in Query Performance and Tuning.

Flexible Replication

MarkLogic. An implementation of replication based on MarkLogic Server Content Processing Framework (CPF). Flexible Replication is single-master, asynchronous, and provides a medium level of throughput and latency. See also Query-Based Flexible Replication (QBFR), domain, pipeline, and Flexible Replication in MarkLogic Server in Use Flexible Replication.

flow

MarkLogic. A series of actions that process the data. Flows are implemented using a chain of plugins that perform sequential or concurrent steps in the process. The two types of flows are input and harmonize. See envelope pattern, Data Hub (DH), and Envelope Pattern - Flows and Plugins in the Data Hub documentation.

flow tracing

MarkLogic. The process that logs information about the flows as they run. Inputs to and outputs from every plugin of every flow are recorded into the JOBS database of the Data Hub. See flow and “Flow Tracing” in the Data Hub documentation.

FLWOR statement (For, Let, Where, Order by, Return)

XQuery. An XQuery programming expression standing for For, Let, Where, Order by, Return. FLWOR (pronounced 'flower') is loosely analogous to SQL's SELECT-FROM-WHERE and can be used to provide join-like functionality to XML documents.

FName

XML. An element identifier used to avoid naming collisions in a namespace.

foaf (friend of a friend)

Semantics. An ontology for describing people and social relationships. See Good Ontologies.

Foreign Bind Port

MarkLogic. The port used on each host to handle XDQP communication with foreign clusters.

Foreign Cluster

MarkLogic. A remote cluster of MarkLogic Server hosts.

forest

MarkLogic. A forest is a collection of documents that is implemented as a physical directory on disk. A group of ‘trees’ (‘Forests, because we store trees.’) A MarkLogic database is made up of ‘forests’. See stand.

forward-chaining inference

Semantics. Forward chaining inference is inference done at index-time - during the ingestion/indexing of triples, creating new, inferred triples and inserting them into the database. Forward-chaining inference is less resource intensive at query-time, but more costly at ingest-time. See also backward-chaining inference and inference.

fragment

MarkLogic. Fragments are XML documents partitioned into smaller blocks of information for storage. You have the option of specifying how the XMP documents are partitioned. See fragments in Administrate MarkLogic Server for more information.

fully searchable expression

Search. An XPath expression that contains no unsearchable path steps and whose last path step is searchable. Such expressions can be efficiently resolved out of the indexes. Only a fully searchable XPath expression can be used as the first argument of cts:search. For more details, see Fully Searchable Paths and cts:search Operations in Query Performance and Tuning.