The MDEX Engine is the indexing and query module used by Guided Search applications to retrieve information that customers request.
The MDEX Engine stores indexes that were created by the Information Transformation Layer (ITL). After the MDEX Engine stores the indexes, it receives client requests through the application tier, queries the indexes, and then returns the results.
The MDEX Engine is stateless. This design requires that a complete query be sent to the MDEX Engine for each request. The stateless design of the MDEX Engine facilitates the addition of MDEX Engine servers for load balancing and redundancy. Because the MDEX Engine is stateless, any replica of an MDEX Engine on one server can reply to queries independently of a replica on other MDEX Engine servers.
Adding replicas of MDEX Engines on additional servers improves query response time. Load balancers can further improve total response time by distributing queries to a replica MDEX Engine on any of the additional servers. Adding replicas also provides redundancy -- that is, if one server goes down, a replica of an MDEX Engine provides redundancy by enabling other servers in the implementation to continue to reply to queries.
The MDEX Engine package contains the following components:
|
MDEX Engine Component |
Description |
|---|---|
|
dgraph |
The dgraph is the name of the process for the MDEX Engine. A typical Guide Search application includes one or more dgraphs. |
|
dgidx |
dgidx is the indexing program that reads the tagged records that were prepared by Forge or CAS and creates the proprietary indexes for the MDEX Engine. |
|
dgwordlist |
The
|
|
generateSSLCertificates |
The
|
