barcode vb.net 2010 ORDER_FACTS day_key product_key salesrep_key company_key . . . order_dollars . . . in Software

Create Quick Response Code in Software ORDER_FACTS day_key product_key salesrep_key company_key . . . order_dollars . . .

ORDER_FACTS day_key product_key salesrep_key company_key . . . order_dollars . . .
Decoding QR-Code In None
Using Barcode Control SDK for Software Control to generate, create, read, scan barcode image in Software applications.
Quick Response Code Generation In None
Using Barcode encoder for Software Control to generate, create QR Code image in Software applications.
COMPANY company_key company_id company_name company_type . . . Role: Transacted With
QR Code ISO/IEC18004 Recognizer In None
Using Barcode recognizer for Software Control to read, scan read, scan image in Software applications.
Draw QR Code ISO/IEC18004 In Visual C#
Using Barcode drawer for VS .NET Control to generate, create QR Code JIS X 0510 image in .NET framework applications.
PRODUCT
Generating QR Code In Visual Studio .NET
Using Barcode maker for ASP.NET Control to generate, create QR Code JIS X 0510 image in ASP.NET applications.
QR Code Creation In .NET
Using Barcode drawer for .NET Control to generate, create QR-Code image in Visual Studio .NET applications.
COMPANY_ HIERARCHY_ BRIDGE superior_company_key subordinate_company_key levels_removed
QR Drawer In Visual Basic .NET
Using Barcode drawer for VS .NET Control to generate, create QR Code image in VS .NET applications.
Printing UCC - 12 In None
Using Barcode encoder for Software Control to generate, create UPC-A image in Software applications.
SALESREP
Data Matrix Creation In None
Using Barcode drawer for Software Control to generate, create Data Matrix image in Software applications.
USS Code 39 Printer In None
Using Barcode printer for Software Control to generate, create Code 3/9 image in Software applications.
COMPANY company_ key 1 2 3 4 5 6 7 8 company_ name Company 1 Company 2 Company 3 Company 4 Company 5 Company 6 Company 7 Company 8
Painting UCC.EAN - 128 In None
Using Barcode printer for Software Control to generate, create EAN 128 image in Software applications.
Generate Bar Code In None
Using Barcode generator for Software Control to generate, create barcode image in Software applications.
Figure 10-5 A star with a standard company dimension and a separate bridge
Generating Code 93 In None
Using Barcode creator for Software Control to generate, create Code 93 Full ASCII image in Software applications.
Recognize GTIN - 13 In VB.NET
Using Barcode recognizer for .NET Control to read, scan read, scan image in Visual Studio .NET applications.
10 Recursive Hierarchies and Bridges 229
GS1 DataBar Stacked Generation In VS .NET
Using Barcode generator for .NET Control to generate, create GS1 DataBar Truncated image in Visual Studio .NET applications.
Barcode Generator In Java
Using Barcode maker for Java Control to generate, create barcode image in Java applications.
shortly. The important point here is that the star can be used without the bridge. If a user wants to group orders by the companies that placed them, the bridge is not needed. This means that the bridge table does not need to be built at the same time as the star; it can be added later. Without it, of course, there is no representation of the relationships between companies.
Scan Code 128 Code Set B In None
Using Barcode recognizer for Software Control to read, scan read, scan image in Software applications.
Bar Code Drawer In Objective-C
Using Barcode generation for iPhone Control to generate, create bar code image in iPhone applications.
Structure and Content of a Hierarchy Bridge Table
Painting Matrix Barcode In Visual Basic .NET
Using Barcode encoder for .NET framework Control to generate, create Matrix 2D Barcode image in Visual Studio .NET applications.
Data Matrix Generation In None
Using Barcode drawer for Font Control to generate, create ECC200 image in Font applications.
The structure of a hierarchy bridge table is quite simple, but it is crucial to understand the nature of its contents. If you have dealt with a recursive relationship in an operational system, you may find the content of the bridge table to be familiar. Similar tables are often constructed to ease the process of operational reporting.
Structure of the Bridge Table Each row of a hierarchy bridge table captures a relationship between a pair of rows in the dimension table. In order to do this, the bridge table has two foreign key columns that refer to the dimension. One represents the higher-level entity in the relationship, and the other represents the lower-level entity. See the sidebar later in this chapter for tips on naming these columns. The company_hierarchy_bridge table in Figure 10-5 captures relationships between companies. It has a pair of foreign keys that refer to the company dimension. The relationships themselves have not been drawn in the picture; that will be done soon enough. For now, note that the column representing the upper-level company in a given relationship is called superior_company_key; the column representing the lower-level company is called subordinate_company_key. Unlike other tables you may have seen, a bridge table does not contain rows only for direct relationships. It also contains rows that represent indirect relationships, where the companies are more than one level apart from one another. In Figure 10-2, for example, Company 1 is two levels away from Company 3. A bridge table will capture indirect relationships like this one as well. An optional column in the bridge table describes how many hierarchy levels separate the two members. In Figure 10-5, this column is called levels_removed.
TIP A hierarchy bridge table contains two foreign keys which refer to related rows in the dimension table. Optionally, it may include an additional column to indicate how far apart the two dimension rows are from one another in the hierarchy. This basic design can be supplemented with additional columns, which will be described later in the chapter. First, though, it is necessary to look at the content of the bridge table.
Content of the Bridge Table As previously noted, each row in a bridge table will represent a relationship between rows in the dimension table. These relationships are identified and populated during the ETL process by traversing the recursive relationships in the source data. This can be done in various ways, but it is easiest to describe the content of the table as follows.
Part III
PART III
Dimension Design
For each row in the dimension table, the hierarchy bridge table will contain one or more rows: One row for each of its direct subordinates, if any. These are members that are one level away in the hierarchy. One row for each of its indirect subordinates, if any. These are members that are two or more levels away from it in the hierarchy. One row for itself (zero levels away). If this last bullet puzzles you, hang on for a few moments. You will see why it is necessary when we look at how the bridge table is used. First, look at some examples. Before studying the company hierarchy, consider a simpler example. For a threemember hierarchy where A is the parent of B and B is the parent of C, it will be necessary to record a total of six rows in the bridge table. For A, we will need the following rows: A s relationship to B (one level removed) A s relationship to C (two levels removed) A s relationship to A (zero levels removed) For B, we will need to record the following relationships: B s relationship to C (one level removed) B s relationship to B (zero levels removed) And for C, we will need to record just one row, since it has no subordinates: C s relationship to C (zero levels removed) It should be obvious from this simple example that a hierarchy bridge table will contain more rows than the dimension table. Now let s return to the company example, which is a bit more involved. The example in Figure 10-6 shows the content of the company hierarchy bridge table. So that you do not need to flip around while you study it, this figure repeats the hierarchy tree from Figure 10-2 and the bridge table design from Figure 10-5. Remember that in this example, company_keys correspond to company names. Choose any company in the hierarchy tree and look for the rows in the bridge table where that company s key is recorded in the first column, superior_company_key. You should find a row that relates the company you have chosen to itself (zero levels), a row that relates it to each subordinate (one level) and a row that relates it to each indirect subordinate (two or more levels). Trace through and make sure you can do this. The number of rows you found depends on the company you chose. Bottom-level companies (3, 4, 7, and 8) have one row in the bridge table, since they have no subordinates. The top-level company (1) has numerous rows, since it is related to each company in the tree. The mental exercise you just completed is an example of looking down the hierarchy. You chose a particular company in which you had an interest, and looked for its key value in superior_company_key. In the rows that you found, the subordinate_company_key represented companies at or below the company you chose.
Copyright © OnBarcode.com . All rights reserved.