16
The Impression Fact

Oracle9i Clickstream Intelligence provides the following facts to support routine traffic analysis:

• Impression fact - Contains facts that are aggregated into logical page views. Each fact in the Impression fact table corresponds to a single request for a page.

• Session fact - Contains facts that are aggregated into individual sessions.

The individual page impression, or page view, marks the granularity of the Impression fact. One record exists in the Impression fact for each logical page request that occurs during any given session.

Both the Impression dimension and the Session dimension (Chapter 17) are degenerate. These dimensions are used solely as a means of grouping events that belong to the same logical impression (Impression dimension) or logical session (Session dimension.) Since both dimension are degenerate, there are no associated dimension tables.

Impression Fact Attributes

Attributes for the Impression fact table consist of measures and foreign keys to the dimensions. For each attribute, information is provided in the appropriate format below:

• Foreign Key: Description (Dimension to which the foreign key refers, if any)

• Measure: Description

In addition to the pre-defined attributes, the Impression fact contains ten "generic" foreign keys and five "generic" measures that can be defined by the user.

Foreign Keys

• Impression_ID : Degenerate Impression dimension key that can be used to correlate specific page views with other events.

• Site_ID: Site dimension foreign key. (Site dimension)

• Session_ID: Degenerate Session dimension key that groups page views into logical sessions to support aggregation.

• Impr_Date_ID : Calendar day at the beginning of this page view, localized to the site time zone. (Date dimension)

• Impr_Time_ID : Time of day at the beginning of this page view, localized to the site time zone. (Time of Day dimension)

• Sess_Date_ID : Calendar day at the beginning of this session, localized to the site time zone. (Date dimension)

• Sess_Time_ID : Time of day at the beginning of this session, localized to the site time zone. (Time of Day dimension)

• Agent_ID: Agent dimension foreign key (Agent dimension)

• First_Agent_ID : First agent of this session (Agent dimension)

• Client_Host_ID : Client host dimension foreign key. (Client Host dimension)

• First_Client_Host_ID: First client host of this session. (Client Host dimension)

• Server_ID : Server dimension foreign key. (Server dimension)

• Server_Status_ID: Server status dimension foreign key. (Server Status dimension)

• Page_ID : Current requested page; the identifying page requested as part of this impression. While an impression may contain several resource requests, including the page resource itself, each impression contains only one requested page. (Page dimension)

• First_Page_ID: First page in this session. (Page dimension)

• Last_Page_ID: Last page in this session. (Page dimension)

• Event_Type_ID : Event type dimension foreign key. (Event Type dimension)

• Session_Type_ID: Session type dimension foreign key. (Session Type dimension)

• Referrer_ID: Immediate internal or external referrer for this particular impression. (Referrer dimension)

• First_Referrer_ID: First referrer of this session; the referrer that initiated the session. (Referrer dimension)

• First_Ref_Search_ID: If the session referrer is a search engine, then this is the search phrase that resulted in a reference to this page. (Search dimension)

• Local_Search_ID: If this page is a "search results" page, then this is the search expression that produced this particular results page. This particular use of the Search dimension is distinguished from Referrer_Search_ID by the fact that this is a local search. (Search dimension)

• User_ID : The actual User dimension foreign key taken directly from the server logs. (User dimension)

• Session_User_ID : User dimension foreign key inferred from the session. (User dimension)

• Visitor_ID : The actual Visitor dimension foreign key taken directly from the server logs. (Visitor dimension)

• Session_Visitor_ID: Visitor dimension foreign key inferred from the client host. (Visitor dimension)

• (Prev_Page10_ID : Tenth previous page in this session, relative to the current page. (Page dimension)

• Prev_Page09_ID: Ninth previous page in this session, relative to the current page. (Page dimension)

• Prev_Page08_ID : Eighth previous page in this session, relative to the current page. (Page dimension)

• Prev_Page07_ID : Seventh previous page in this session, relative to the current page. (Page dimension)

• Prev_Page06_ID : Sixth previous page in this session, relative to the current page. (Page dimension)

• Prev_Page05_ID : Fifth previous page in this session, relative to the current page. (Page dimension)

• Prev_Page04_ID: Fourth previous page in this session, relative to the current page. (Page dimension)

• Prev_Page03_ID : Third previous page in this session, relative to the current page. (Page dimension)

• Prev_Page02_ID: Second previous page in this session, relative to the current page. (Page dimension)

• Prev_Page01_ID : Immediate previous page in this session, relative to the current page. (Page dimension)

• Next_Page01_ID : Immediate next page in this session, relative to the current page. (Page dimension)

• Next_Page02_ID : Second next page in this session, relative to the current page. (Page dimension)

• Next_Page03_ID: Third next page in this session, relative to the current page. (Page dimension)

• Next_Page04_ID: Fourth next page in this session, relative to the current page. (Page dimension)

• Next_Page05_ID: Fifth next page in this session, relative to the current page. (Page dimension)

• Next_Page06_ID: Sixth next page in this session, relative to the current page. (Page dimension)

• Next_Page07_ID: Seventh next page in this session, relative to the current page. (Page dimension)

• Next_Page08_ID: Eighth next page in this session, relative to the current page. (Page dimension)

• Next_Page09_ID: Ninth next page in this session, relative to the current page. (Page dimension)

• Next_Page10_ID: Tenth next page in this session, relative to the current page. (Page dimension)

• Dim01_ID : Generic dimension 01 foreign key

• Dim02_ID: Generic dimension 02 foreign key

• Dim03_ID: Generic dimension 03 foreign key

• Dim04_ID : Generic dimension 04 foreign key

• Dim05_ID : Generic dimension 05 foreign key

• Dim06_ID : Generic dimension 06 foreign key

• Dim07_ID : Generic dimension 07 foreign key

• Dim08_ID : Generic dimension 08 foreign key

• Dim09_ID: Generic dimension 09 foreign key

• Dim10_ID : Generic dimension 10 foreign key

Measures

• Bytes_From_Server : Total number of bytes, excluding HTTP headers, transferred from the server to the client for this page view.

• Bytes_From_Client : Total number of bytes, excluding HTTP headers, transferred from the client to the server for this page view.

• Impression_Duration : Elapsed time for this page view, defined as the length of time from this impression until the next impression in the session.

• Impression_Time_To_Serve: Amount of time in seconds taken by the server to process and serve this page view.

• Impression_Dwell_Time: Equal to (Impression_Duration - Impression_Time_To_Serve)

• Sequence_In_Session: Sequence number that captures the temporal relationships between page views in the context of a particular session. The sequence indicated by this attribute is only valid in the context of a single session.

• Measure01: User-defined measure 01

• Measure02 : User-defined measure 02

• Measure03 : User-defined measure 03

• Measure04 : User-defined measure 04

• Measure05 : User-defined measure 05