Abstract:
An event reporting system includes a computational component  228  operable (a) to receive notification of a change to an attribute of an entity, the entity, prior to the change, being associated with a first surrogate key, and (b) to defer the use of a second surrogate key for the entity until a selected time. The second surrogate key was generated to reflect the change.

Description:
FIELD OF THE INVENTION 
     The present invention is directed generally to event processing and specifically to monitoring agent performance. 
     BACKGROUND OF THE INVENTION 
     Contact centers, such as Automatic Call Distribution or ACD systems, are employed by many enterprises to service customer contacts. A typical contact center includes a switch and/or server to receive and route incoming packet-switched and/or circuit-switched contacts and one or more resources, such as human agents and automated resources (e.g., Interactive Voice Response (IVR) units), to service the incoming contacts. Contact centers distribute contacts, whether inbound or outbound, for servicing to any suitable resource according to predefined criteria. In many existing systems, the criteria for servicing the contact from the moment that the contact center becomes aware of the contact until the contact is connected to an agent are customer-specifiable (i.e., programmable by the operator of the contact center), via a capability called vectoring. Normally in present-day ACDs when the ACD system&#39;s controller detects that an agent has become available to handle a contact, the controller identifies all predefined contact-handling skills of the agent (usually in some order of priority) and delivers to the agent the highest-priority oldest contact that matches the agent&#39;s highest-priority skill. Generally, the only condition that results in a contact not being delivered to an available agent is that there are no contacts waiting to be handled. 
     The primary objective of contact center management, including call-distribution algorithms, is to ultimately maximize contact center performance and profitability. An ongoing challenge in contact center administration is monitoring of agent behaviors to optimize the use of contact center resources and maximize agent performance and profitably. Current products for monitoring and reporting on contact center performance, such as Call Management System or CMS™ by Avaya, Inc., are configured as data warehouses that extract data from multiple sources, transform the data into a normalized form, and load the data into the data warehouse database, typically on a batch schedule. Additional calculations and reporting are performed after the batch load. 
     A common type of data warehouse is based on dimensional modeling. Dimensional modeling is a data model that divides the world into measurements and context. Measurements are usually numeric and taken repeatedly. Numeric measurements are facts. Facts are surrounded by textual context in existence when the fact is recorded. Context is often subdivided into dimensions. Fact tables are used in dimensional modeling to logically model measurements with multiple foreign keys referring to the contextual entities. The contextual entities each have an associated primary key. A “key” is a data element (e.g., attribute or column) that identifies an instance of an entity or record in a collection of data, such as a table. A “primary key” is a column or combination of columns whose values uniquely identify a row in a table or is the attribute or group of attributes selected from the candidate keys as the most suitable to uniquely identify each instance of an entity. A “foreign key” refers to a column or combination of columns whose values are required to match a primary key in another table or is a primary key of a parent entity that contributes to a child entity across a relationship. Types of primary keys include a natural key, or a key having a meaning to users, and a surrogate key, or a key that is artificially or synthetically established, meaningless to users, and used as a substitute for a natural key. 
     If the same entity (e.g., agent) is represented on multiple data sources (e.g., inbound call system and outbound call system) by different natural keys, a traditional data warehouse generates and assigns a surrogate key to identify the entity. The surrogate key is an internal identifier managed by the data warehouse. For example, in a contact center an agent may handle inbound calls from one system and outbound calls from another system, with different identities on each system. Data warehouses commonly process each data source independently, performing data correlation across sources at a later time. This approach is normally unworkable when events for the same entity from multiple sources must be processed simultaneously in real time, such as in the blended inbound/outbound call center. For this reason, existing contact center data warehouse products that combine data from multiple sources appear to merely process each source independently, with little or no correlation when the same entity is represented on multiple sources. 
     Some data models specify a behavior known as a type 2 slowly changing dimension. A type 2 dimension tracks the history of changes to an entity over time. When an attribute of an entity is changed, such as when a contact center agent changes their skill set or group membership, a new surrogate key for that entity is generated, and a new row inserted into the database. Fact data associated with the entity can now be tracked separately for activities that occurred before versus after the change by referencing the appropriate surrogate key. 
     The traditional technique for handling a type 2 dimension update is to associate the change with a specific point in time. If that point in time occurs in the middle of a logical transaction, there is a potential for performing incorrect data correlation. This problem is exacerbated for real time data warehouse application where the application must handle entities with multiple natural keys that also have multiple surrogate keys due to type 2 dimensions. Because an entity has multiple natural keys, a surrogate key must be used to track fact data for the entity. If the application performs calculations in real time that span a type 2 dimension change that caused a new surrogate key to be created, the result of the calculation may be indeterminate or incorrect. For example, a contact center application may track the amount of time an agent places callers on hold. If a type 2 dimension change occurs to the agent dimension while the agent has a caller on hold, a new surrogate key is generated. The application then cannot easily calculate the hold time because the start and end times are associated with different fact records with different surrogate keys. The problem expands when considering data consistency across individual calls, multiple related calls, or agent login sessions that may span hours. 
     SUMMARY OF THE INVENTION 
     These and other needs are addressed by the various embodiments and configurations of the present invention. The present invention is directed generally to sequencing the use of different surrogate keys associated with a common entity. 
     In a first embodiment, a method for correlating information is provided that includes the steps: 
     (a) receiving notification of a change to an attribute of an entity, the entity, prior to the change, being associated with a first surrogate key; and 
     (b) deferring the use of a second surrogate key, generated in response to the change, until a selected time. The entity and associated attribute can be context or a measurement. Typically, the entity is a dimension and the attribute is a fact. 
     In a second embodiment, a method for correlating information is provided that includes the steps: 
     (a) receiving an event notification, the event notification comprising event information and a natural key; 
     (b) mapping the natural key to a normalized key; and 
     (c) selecting a first hint for the normalized key, the first hint indicating which of a plurality of surrogate keys associated with the normalized key will be used in a record corresponding to the event information. An event is an occurrence or happening. A normalized key is a type of surrogate key used to reference an entity associated with a natural key. A hint can be any information influencing the selection of a first surrogate key over a second surrogate key. The hint is preferably a form of instruction indicating when a selected surrogate key is valid for use. 
     In one exemplary configuration, multiple natural keys for the same entity from multiple sources are mapped to the normalized key. Multiple surrogate keys are also maintained to support type 2 dimensions. The normalized key is used to manage facts for an entity prior to storing the facts in the database. When a new type 2 surrogate key is generated, the hint is provided to the event processor, allowing the processor to decide when to allow the new surrogate key to take effect based on knowledge of the entity state or other business conditions. Until the entity is in a state where calculated facts are consistent according to business operations, facts stored in the database are associated with the previous surrogate key. 
     By using a normalized key that is separate from both the natural keys and the type 2 surrogate keys, it becomes possible to perform calculations for an entity in real time without regard to the multiple representations of the entity at the sources and the multiple type 2 dimension representations in the database. Type 2 dimension semantics are maintained by deferring the time when a new type 2 surrogate key takes effect in the fact data until the entity is in an acceptable state, such as at the end of the current contact or after the agent has completed his or her daily shift. The specific time of deferral is determined in real time by the events processed from the multiple input sources, such as based on rules encoded in a specification or coded in software. 
     The invention can allow events for the same entity from multiple sources to be consolidated and summarized in real time into a data model that supports type 2 dimension semantics, without introducing data anomalies that could occur due to real time updates to the type 2 surrogate keys. 
     These and other advantages will be apparent from the disclosure of the invention(s) contained herein. 
     As used herein, “at least one”, “one or more”, and “and/or” are open-ended expressions that are both conjunctive and disjunctive in operation. For example, each of the expressions “at least one of A, B and C”, “at least one of A, B, or C”, “one or more of A, B, and C”, “one or more of A, B, or C” and “A, B, and/or C” means A alone, B alone, C alone, A and B together, A and C together, B and C together, or A, B and C together. 
     The above-described embodiments and configurations are neither complete nor exhaustive. As will be appreciated, other embodiments of the invention are possible utilizing, alone or in combination, one or more of the features set forth above or described in detail below. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a block diagram depicting a contact center according to an embodiment of the present invention; 
         FIG. 2  is a block diagram of a server according to an embodiment of the present invention; 
         FIG. 3  is a block diagram depicting an embodiment of the event processing module; 
         FIG. 4  is a signal flow diagram according to an embodiment of the present invention; and 
         FIG. 5  is a flow chart depicting an operational embodiment of the event processing module. 
     
    
    
     DETAILED DESCRIPTION 
     The invention will be illustrated below in conjunction with an exemplary communication system. Although well suited for use with, e.g., a system having an ACD or other similar contact processing switch, the invention is not limited to use with any particular type of communication system switch or configuration of system elements. Those skilled in the art will recognize that the disclosed techniques may be used in any communication application in which it is desirable to provide improved event (e.g., contact) processing. 
       FIG. 1  shows an illustrative embodiment of the present invention. A contact center  100  comprises a central server  110 , a set of data stores or databases  114  containing contact or customer related information and other information that can enhance the value and efficiency of the contact processing, and a plurality of servers, namely a voice mail server  118 , an Interactive Voice Response unit or IVR  122 , and other servers  126  (such as a predictive dialer), a switch  130 , a plurality of working agents operating packet-switched (first) telecommunication devices  134 - 1  to N (such as computer work stations or personal computers), and/or circuit-switched (second) telecommunication devices  138 - 1  to M, all interconnected by a local area network LAN (or wide area network WAN)  142 . The servers can be connected via optional communication lines  146  to the switch  130 . As will be appreciated, the other servers  126  can also include a scanner (which is normally not connected to the switch  130  or Web server), VoIP software, video call software, voice messaging software, an IP voice server, a fax server, a web server, and an email server and the like. The switch  130  is connected via a plurality of trunks  150  to the Public Switch Telecommunication Network or PSTN  154  and via link(s)  152  to the second telecommunication devices  138 - 1  to M. A gateway  158  is positioned between the server  110  and the packet-switched network  162  to process communications passing between the server  110  and the network  162 . 
     The term “switch” or “server” as used herein should be understood to include a PBX, an ACD, an enterprise switch, or other type of telecommunications system switch or server, as well as other types of processor-based communication control devices such as media servers, computers, adjuncts, etc. 
     Referring to  FIG. 2 , one possible configuration of the server  110  is depicted. The server  110  is in communication with a plurality of customer communication lines  200   a - y  (which can be one or more trunks, phone lines, etc.) and agent communication line  204  (which can be a voice-and-data transmission line such as LAN  142  and/or a circuit switched voice line  140 ). The server  110  can include an event processing module  228 , such as a modified form of Basic Call Management System™ or BCMS, Call Management System™, and/or Operational Analyst™ by Avaya, Inc., that gathers call records and contact-center statistics for use in generating contact-center reports. 
     The switch  130  and/or server  110  can be any architecture for directing contacts to one or more telecommunication devices. Illustratively, the switch and/or server can be a modified form of the subscriber-premises equipment disclosed in U.S. Pat. Nos. 6,192,122; 6,173,053; 6,163,607; 5,982,873; 5,905,793; 5,828,747; and 5,206,903, all of which are incorporated herein by this reference; Avaya Inc.&#39;s Definity™ Private-Branch Exchange (PBX)-based ACD system; MultiVantage™ PBX, CRM Central 2000 Server™, Communication Manager™, S8300™ media server, and/or Avaya Interaction Center™ Typically, the switch/server is a stored-program-controlled system that conventionally includes interfaces to external communication links, a communications switching fabric, service circuits (e.g., tone generators, announcement circuits, etc.), memory for storing control programs and data, and a processor (i.e., a computer) for executing the stored control programs to control the interfaces and the fabric and to provide automatic contact-distribution functionality. The switch and/or server typically include a network interface card (not shown) to provide services to the serviced telecommunication devices. Other types of known switches and servers are well known in the art and therefore not described in detail herein. 
     Referring to  FIG. 2 , included among the data stored in the server  110  is a set of contact queues  208   a - n  and a separate set of agent queues  212   a - n . Each contact queue  208   a - n  corresponds to a different set of agent skills, as does each agent queue  212   a - n . Conventionally, contacts are prioritized and either are enqueued in individual ones of the contact queues  208   a - n  in their order of priority or are enqueued in different ones of a plurality of contact queues that correspond to a different priority. Likewise, each agent&#39;s skills are prioritized according to his or her level of expertise in that skill, and either agents are enqueued in individual ones of agent queues  212   a - n  in their order of expertise level or are enqueued in different ones of a plurality of agent queues  212   a - n  that correspond to a skill and each one of which corresponds to a different expertise level. Included among the control programs in the server  110  is a contact vector  216 . Contacts incoming to the contact center are assigned by contact vector  216  to different contact queues  208   a - n  based upon a number of predetermined criteria, including customer identity, customer needs, contact center needs, current contact center queue lengths, customer value, and the agent skill that is required for the proper handling of the contact. Agents who are available for handling contacts are assigned to agent queues  212   a - n  based upon the skills that they possess. An agent may have multiple skills, and hence may be assigned to multiple agent queues  212   a - n  simultaneously. Furthermore, an agent may have different levels of skill expertise (e.g., skill levels  1 -N in one configuration or merely primary skills and secondary skills in another configuration), and hence may be assigned to different agent queues  212   a - n  at different expertise levels. Call vectoring is described in DEFINITY Communications System Generic 3 Call Vectoring/Expert Agent Selection (EAS) Guide, AT&amp;T publication no. 555-230-520 (Issue 3, November 1993). Skills-based ACD is described in further detail in U.S. Pat. Nos. 6,173,053 and 5,206,903. 
     Referring to  FIG. 1 , the gateway  158  can be Avaya Inc.&#39;s, G700 Media Gateway™ and may be implemented as hardware such as via an adjunct processor (as shown) or as a chip in the server. 
     The first telecommunication devices  134 - 1 , . . .  134 -N are packet-switched and can include, for example, IP hardphones such as the Avaya Inc.&#39;s, 4600 Series IP Phones™, IP softphones such as Avaya Inc.&#39;s, IP Softphone™, Personal Digital Assistants or PDAs, Personal Computers or PCs, laptops, packet-based H.320 video phones and conferencing units, packet-based voice messaging and response units, packet-based traditional computer telephony adjuncts, and any other communication device. 
     The second telecommunication devices  138 - 1 , . . .  138 -M are circuit-switched. Each of the telecommunication devices  138 - 1 , . . .  138 -M corresponds to one of a set of internal extensions Ext 1 , . . . ExtM, respectively. These extensions are referred to herein as “internal” in that they are extensions within the premises that are directly serviced by the switch. More particularly, these extensions correspond to conventional telecommunication device endpoints serviced by the switch/server, and the switch/server can direct incoming calls to and receive outgoing calls from these extensions in a conventional manner. The second telecommunication devices can include, for example, wired and wireless telephones, PDAs, H.320 video phones and conferencing units, voice messaging and response units, traditional computer telephony adjuncts, and any other communication device. 
     It should be noted that the invention does not require any particular type of information transport medium between switch or server and first and second telecommunication devices, i.e., the invention may be implemented with any desired type of transport medium as well as combinations of different types of transport channels. 
     The packet-switched network  162  can be any data and/or distributed processing network, such as the Internet. The network  162  typically includes proxies (not shown), registrars (not shown), and routers (not shown) for managing packet flows. 
     The packet-switched network  162  is in communication with an external first telecommunication device  174  via a gateway  178 , and the circuit-switched network  154  with an external second telecommunication device  180 . These telecommunication devices are referred to as “external” in that they are not directly supported as telecommunication device endpoints by the switch or server. The telecommunication devices  174  and  180  are an example of devices more generally referred to herein as “external endpoints.” 
     In a preferred configuration, the server  110 , network  162 , and first telecommunication devices  134  are Session Initiation Protocol or SIP compatible and can include interfaces for various other protocols such as the Lightweight Directory Access Protocol or LDAP, H.248, H.323, Simple Mail Transfer Protocol or SMTP, IMAP4, ISDN, E1/T1, and analog line or trunk. 
     It should be emphasized that the configuration of the switch, server, user telecommunication devices, and other elements as shown in  FIG. 1  is for purposes of illustration only and should not be construed as limiting the invention to any particular arrangement of elements. 
     As will be appreciated, the central server  110  is notified via LAN  142  of an incoming contact by the telecommunications component (e.g., switch  130 , fax server, email server, web server, and/or other server) receiving the incoming contact. The incoming contact is held by the receiving telecommunications component until the server  110  forwards instructions to the component to forward or route the contact to a specific contact center resource, such as the IVR unit  122 , the voice mail server  118 , and/or first or second telecommunication device  134 ,  138  associated with a selected agent. The server  110  distributes and connects these contacts to telecommunication devices of available agents based on the predetermined criteria noted above. When the central server  110  forwards a voice contact to an agent, the central server  110  also forwards customer-related information from databases  114  to the agent&#39;s computer work station for previewing and/or viewing (such as by a pop-up display) to permit the agent to better serve the customer. The agents process the contacts sent to them by the central server  110 . 
       FIG. 3  depicts an embodiment of the event processing module  228 . The module  228  includes first, second, . . . nth input adapters for normalizing event information received from first, second, . . . nth sources (which may include computational components in the server  110 , switch  130 , IVR  122 , other servers  126 , and the like), a plurality of event processors  308   a - m  for generating event-related data from normalized event information, a plurality of data stores  316   a - p  for storing the event-related data, a plurality of output adapters  312   a - o  to effect storage of the event-related data in a data store  316 , an Identity Resolution Service or IRS  320  for providing a unique identifier known as the Entity Identifier or ED for each entity instance, and a key authority  324  to generate surrogate keys and hints. 
     The input adapters  300   a - n  obtain events from a source system and normalize the received events into normalized event information. Normalized event information is a pre-defined set of events that conform to specific syntax and semantic rules. The input adapters translate source-specific events from source-specific formats to normalized events. One of the translation functions is the conversion of natural keys to normalized keys, namely EIDs or a type of surrogate key. EIDs are immutable keys that do not change for the life of an entity compared to surrogate keys for type 2 dimensions that often change over time. Another example of normalization is the conversion of time stamps in source notifications to a common time zone. Input adapters normally do not hold state or process events except as necessary to generate normalized event information. The output of the input adapters includes normalized events that identify entities by their EIDs rather than source-specific natural key identifiers. 
     Event processors  308   a - m  use the normalized event information to generate detail and/or state and summary data for storage in a data store. Serial data would also be generated by the event processor when there is a distinction between detail and serial data. The event processor rationalizes entity states across multiple sources, producing a single state for each entity instance. Late arriving events can be handled by staging events in the event processor, such as using a lightweight local database. The tolerance for late arriving events is much lower for real-time data than for historical data; therefore, it is possible that the real-time data shows temporarily incorrect state data that is corrected in the historical data by the longer tolerance for late arriving events. In a preferred configuration, different event processors handle real-time and historic events and the events are stored in separate real-time and historic data stores. 
     The data stores are preferably configured in accordance with dimensional modeling concepts. In other words, facts are associated with context and grouped into fact tables. Context is further subdivided into dimensions. Exemplary dimensions include work item (e.g., type, class, etc.), customer (e.g., identity, class, etc.), agent (e.g., identity, skills, etc.), routing (e.g., how work item was processed/routed, routing destination, etc.), class (e.g., inbound, outbound, internal, external, etc.), time (e.g., time stamp (date and time) of when an event occurred), state (e.g., state of agent, state of customer, state of work item, etc.), exit reason (e.g., reason for state change, etc.) and delivery method (e.g., direct, distributed, etc.) and/or an action involving one or more of the foregoing, such as arrival of a work item, agent state change, and the like. An event is typically associated with (structured) context. For example, events may be associated with and/or are instances of the foregoing dimensions. A measure refers to a set of events having a defined relationship. Generally, an event is a point in time while a measure is a temporal duration or a count of event occurrences. 
     The output adapters  312  are responsible for converting processed normalized event information received from the event processors into the form required for an external destination, such as Structured Query Language or SQL, for a database. They perform translation functions, such as converting EID&#39;s to the surrogate keys required by the data model but they generally do not hold state or process the events. All context required to generate the output is included in the processed normalized event information, such as in the form of metadata. The output adapters are thus context-free. In one configuration, one or more of the output adapters handles historic events and one or more other output adapters handles real-time events. The historical and real-time output adapters cleanse the data from the disparate event processors, which includes resolving identifiers into surrogate keys, creating new rows based on type 2 dimensions when necessary, generating multiple timestamp formats in different time zones, and the like. 
     The IRS  320  translates source-specific identifiers or keys into EIDs for each entity instance and provide a hint. As will be appreciated, entities often have multiple natural keys as defined the source systems. For example, an agent who performs inbound and outbound work will have different identifiers on the server  110  and predictive dialing system. Some entities, such as contacts and customers, may be associated with multiple instances of the same type of source, such as when a call is transferred from one site to another or a customer calls into different sites. In all of these cases, the natural keys must be resolved into a single identifier that allows event processing to uniquely identify each source entity. Otherwise the data will be correlated incorrectly, causing erroneous or misleading data to be displayed on reports. The EID can be obtained from tables stored locally to the IRS and/or from the key authority  324 . 
     The key authority  324  manages surrogate keys. When an administration change causes a new surrogate key to be generated, the key authority  324  sends the BID to the IRS along with the hint that a new surrogate key is available. The normalized event notification from the input adapter to the event processor includes the hint as payload along with the EID. The event processor uses the hint and other state information to decide when the new surrogate key should take effect. For example, the new key may take effect after the agent logs out or after the agent&#39;s current call completes. The key authority is used by the output adapter to determine the current surrogate key for an entity instance. 
     The hint is preferably a form of instruction indicating when a surrogate key is valid for use. Examples of hints include a yes/no flag regarding availability of the surrogate key for current use, a date and/or time after which the surrogate key is valid, a signature indicating that the key is valid, an identified event which must occur before the key is valid, a time stamp (such as of the EID request), the surrogate key itself, a sequence number and the like. In one embodiment, the hint is used by the key authority to map from an EID to the valid surrogate key. 
       FIGS. 4A-B  show differing architectures for signal flows among the above components.  FIG. 4A  assumes that the IRS maintains a table of EID&#39;s, hints, and corresponding natural keys. The key authority periodically updates the IRS table with hints for each EID to reflect administration changes. In  FIG. 4B  in contrast, the IRS maintains a table of EID&#39;s and corresponding natural keys but queries the key authority for the hint corresponding to the EID when an EID request is received. 
     Referring to  FIG. 4A , the initial signal is the event notification signal received by an input adapter from a source system. The event notification signal typically includes event information and one or more natural keys corresponding to the event information. The input adapter forwards an EID request to the IRS. The EID request includes the natural key(s) and optionally selected event information. The IRS maps the natural key to a corresponding EID and hint. The IRS forwards the EID and hint to the input adapter in an EID response. The input adapter then forwards a normalized event notification to the event processor. The normalized event notification includes the EID, hint, and normalized event information. The event processor, after receiving the normalized event notification, processes the normalized event information to yield update data, which will be used to update the corresponding record(s) in the data store. The event processor then forwards a data notification to the output adapter. The data notification includes the EID, hint, and update data. The output adapter, in response to receiving the data notification, forwards a key request to the key authority. The key request includes the EID and hint. The key authority, which maintains a table of EID&#39;s and hints and corresponding surrogate keys, maps the EID and hint to yield a surrogate key for use in updating the records in the data store. The surrogate key is returned to the output adapter in a key response. The output adapter then submits an update request containing the surrogate key and normalized information to the application interface of the data store for updating. 
     Referring to  FIG. 4B , the message flow is the same as  FIG. 4A  with the exception of the signals exchanged between the IRS and key authority. While the key authority in  FIG. 4A  periodically forwards EID hint updates to the IRS to update the local table of the IRS, the IRS, in  FIG. 4B , sends a hint request to the key authority each time an ED request is received. The hint request includes the EID from the local table of the IRS. In this configuration, the local table of the IRS does not include hints. The key authority responds with a hint response including a hint corresponding to the EID. 
     The operation of the event processing module  228  will now be discussed with reference to  FIG. 5 . 
     In box  500 , an event notification arrives at an input adapter  300  from a source system  304 . In response, the input adapter  300  forwards an EID request to the IRS  320 . In step  504 , the IRS  320  maps the source-specific key(s), or natural key(s), in the EID request to determine a corresponding pair of EID and hint. Alternatively, the IRS can map to produce an EID and forward the EID to the key authority in a hint request. In either case, the IRS returns the EID and corresponding hint to the input adapter in the EID response. The input adapter then forwards the normalized event notification containing the EID and hint to the event processor. 
     In decision diamond  512 , the event processor determines whether there is a saved hint corresponding to the ED. The event processor maintains a dynamic local table of EID&#39;s and, for each EID, a hint that was last used by the event processor for the EID. If there is no saved hint in the local table, the event processor in step  520  saves the hint in local memory. If there is a saved hint in the local table, the event processor in decision diamond  516  determines whether or not to replace the saved hint with a new hint. 
     The event processor is not required to use only the provided hint but may select a different hint depending on the context of events associated with an entity or other type of dimension. Because the event processor is aware of the current state(s) of source-specific dimensions, such as call state, agent state, and the like, the event processor may replace the provided hint with its own hint to reflect current events. For example if an agent natural key has administratively changed and the key authority hint indicates that a new surrogate key for the agent may now be used, the event processor may question the hint because the event involves a customer contact that the agent has been servicing. If the new surrogate key is used currently, the data structures surrounding the current customer contact would be at best incomplete and at worst misleading. The event processor may therefore replace the hint with a new hint indicating that the old surrogate key is to be used until the current contact is concluded or until the agent&#39;s shift is over. 
     If the event processor determines that the saved hint is to be replaced, processor in step  524  saves the new hint in the local table. If the event processor determines that the saved hint is not to be replaced or after step  524 , the processor forwards the data notification to the output adapter. 
     The output adapter in step  528  uses the hint and EID in the data notification to obtain from the key authority the pertinent surrogate key. This is done by sending to the key authority a key request containing the EID and selected hint. The key authority maps the hint and EID to produce a surrogate key and returns the surrogate key to the output adapter in a key response. 
     Finally, in step  532  the output adapter sends an update request to the data store to write the data to the store. 
     A number of variations and modifications of the invention can be used. It would be possible to provide for some features of the invention without providing others. 
     For example, the server and/or switch can be a software-controlled system including a processing unit (CPU), microprocessor, or other type of digital data processor executing software or an Application-Specific Integrated Circuit (ASIC) as well as various portions or combinations of such elements. The memory may be a random access memory (RAM), a read-only memory (ROM), or combinations of these and other types of electronic memory devices. 
     The present invention, in various embodiments, includes components, methods, processes, systems and/or apparatus substantially as depicted and described herein, including various embodiments, subcombinations, and subsets thereof. Those of skill in the art will understand how to make and use the present invention after understanding the present disclosure. The present invention, in various embodiments, includes providing devices and processes in the absence of items not depicted and/or described herein or in various embodiments hereof, including in the absence of such items as may have been used in previous devices or processes, e.g., for improving performance, achieving ease and\or reducing cost of implementation. 
     The foregoing discussion of the invention has been presented for purposes of illustration and description. The foregoing is not intended to limit the invention to the form or forms disclosed herein. In the foregoing Detailed Description for example, various features of the invention are grouped together in one or more embodiments for the purpose of streamlining the disclosure. This method of disclosure is not to be interpreted as reflecting an intention that the claimed invention requires more features than are expressly recited in each claim. Rather, as the following claims reflect, inventive aspects lie in less than all features of a single foregoing disclosed embodiment. Thus, the following claims are hereby incorporated into this Detailed Description, with each claim standing on its own as a separate preferred embodiment of the invention. 
     Moreover, though the description of the invention has included description of one or more embodiments and certain variations and modifications, other variations and modifications are within the scope of the invention, e.g., as may be within the skill and knowledge of those in the art, after understanding the present disclosure. It is intended to obtain rights which include alternative embodiments to the extent permitted, including alternate, interchangeable and/or equivalent structures, functions, ranges or steps to those claimed, whether or not such alternate, interchangeable and/or equivalent structures, functions, ranges or steps are disclosed herein, and without intending to publicly dedicate any patentable subject matter.