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mini-dimension attribute values to be accessed along with the base dimension's others without linking through a fact table. Logically, we typically represent the base dimension and current mini-dimension profile outrigger as a single table in the presentation layer. The outrigger attributes should have distinct column names, like “Current Income Level,” to differentiate them from attributes in the mini-dimension linked to the fact table. The ETL team must update/overwrite the type 1 mini-dimension reference whenever the current mini-dimension changes over time. If the outrigger approach does not deliver satisfactory query performance, then the mini-dimension attributes could be physically embedded (and updated) in the base dimension.
537:(Supplier_Key) are then permanently bound to the time slices defined by that row of the slowly changing dimension table. An aggregate table summarizing facts by supplier state continues to reflect the historical state, i.e. the state the supplier was in at the time of the transaction; no update is needed. To reference the entity via the natural key, it is necessary to remove the unique constraint making
25:
2127:
184:
tracking sales might be linked to a dimension table containing information about salespeople and their assigned regional offices. If a salesperson is transferred to a new office, historical sales reports need to reflect their previous assignment without breaking the relationships between the fact and
544:
If there are retroactive changes made to the contents of the dimension, or if new attributes are added to the dimension (for example a Sales_Rep column) which have different effective dates from those already defined, then this can result in the existing transactions needing to be updated to reflect
553:
This method tracks changes using separate columns and preserves limited history. The Type 3 preserves limited history as it is limited to the number of columns designated for storing historical data. The original table structure in Type 1 and Type 2 is the same but Type 3 adds additional columns.
160:
Various methodologies address the complexities of SCD management. The
Kimball Toolkit has popularized a categorization of techniques for handling SCD attributes as Type 1 through Type 6. These range from simple overwrites (Type 1) to creating new rows for each change (Type 2), adding new attributes
459:
The Start date/time of the second row is equal to the End date/time of the previous row. The null End_Date in row two indicates the current tuple version. A standardized surrogate high date (e.g. 9999-12-31) may instead be used as an end date, so that the field can be included in an index, and so
161:(Type 3), maintaining separate history tables (Type 4), or employing hybrid approaches (Type 6 and 7). Type 0 is available to model an attribute as not really changing at all. Each type offers a trade-off between historical accuracy, data complexity, and system performance, catering to different
724:
The type 5 technique builds on the type 4 mini-dimension by embedding a “current profile” mini-dimension key in the base dimension that's overwritten as a type 1 attribute. This approach is called type 5 because 4 + 1 equals 5. The type 5 slowly changing dimension allows the currently-assigned
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We overwrite the
Current_State information in the first record (Row_Key = 1) with the new information, as in Type 1 processing. We create a new record to track the changes, as in Type 2 processing. And we store the history in a second State column (Historical_State), which incorporates Type 3
1055:
when the fact data is loaded into the data repository. The surrogate key is selected for a given fact record based on its effective date and the Start_Date and End_Date from the dimension table. This allows the fact data to be easily joined to the correct dimension data for the corresponding
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A fact record with an effective date (Delivery_Date) of August 9, 2001 will be linked to
Supplier_Code of ABC, with a Supplier_State of 'CA'. A fact record with an effective date of October 11, 2007 will also be linked to the same Supplier_Code ABC, but with a Supplier_State of 'IL'.
1170:
Once the
Delivery table contains the correct Supplier_Key, it can easily be joined to the Supplier table using that key. The following SQL retrieves, for each fact record, the current supplier state and the state the supplier was located in at the time of the delivery:
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The Type 4 method is usually referred to as using "history tables", where one table keeps the current data, and an additional table is used to keep a record of some or all changes. Both the surrogate keys are referenced in the fact table to enhance query performance.
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You don't need to reprocess the fact table if there is a change in the dimension table (e.g. adding additional fields retrospectively which change the time slices, or if one makes a mistake in the dates on the dimension table one can correct them
2309:
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item (e.g. each unique supplier has a single surrogate key). This avoids any changes in the master data having an impact on the existing transaction data. It also allows more options when querying the transactions.
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that null-value substitution is not required when querying. In some database software, using an artificial high date value could cause performance issues, that using a null value would prevent.
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Having a Type 2 surrogate key for each time slice can cause problems if the dimension is subject to change. A pure Type 6 implementation does not use this, but uses a surrogate key for each
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Different SCD Types can be applied to different columns of a table. For example, we can apply Type 1 to the
Supplier_Name column and Type 2 to the Supplier_State column of the same table.
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processes needed to create the dimension table needs to be carefully designed to ensure that there are no overlaps in the time periods for each distinct item of reference data.
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For example, if the supplier were to relocate again, we would add another record to the
Supplier dimension, and we would overwrite the contents of the Current_State column:
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The
Current_State and the Historical_State are the same. The optional Current_Flag attribute indicates that this is the current or most recent record for this supplier.
2282:
816:
When Acme Supply
Company moves to Illinois, we add a new record, as in Type 2 processing, however a row key is included to ensure we have a unique key for each row:
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You can join the fact to the multiple versions of the dimension table to allow reporting of the same information with different effective dates, in the same query.
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One variation of this is to create the field
Previous_Supplier_State instead of Original_Supplier_State which would track only the most recent historical change.
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the new situation. This can be an expensive database operation, so Type 2 SCDs are not a good choice if the dimensional model is subject to frequent change.
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The Type 6 method combines the approaches of types 1, 2 and 3 (1 + 2 + 3 = 6). One possible explanation of the origin of the term was that it was coined by
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In the following example, an additional column has been added to the table to record the supplier's original state - only the previous history is stored.
42:
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and/or different version numbers. Unlimited history is preserved for each insert. The natural key in these examples is the "Supplier_Code" of "ABC".
2350:
145:, such as transactional parameters like customer ID, product ID, quantity, and price, which undergo frequent update. Common examples of SCDs include
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If one has calculated an aggregate table summarizing facts by supplier state, it will need to be recalculated when the
Supplier_State is changed.
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The disadvantage of the Type 1 method is that there is no history in the data warehouse. It has the advantage however that it's easy to maintain.
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If there is more than one date on the fact (e.g. Order_Date, Delivery_Date, Invoice_Payment_Date) one can choose which date to use for a query.
193:
The Type 0 dimension attributes never change and are assigned to attributes that have durable values or are described as 'Original'. Examples:
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This record contains a column for the original state and current state—cannot track the changes if the supplier relocates a second time.
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The following example shows how a specific date such as '2012-01-01T00:00:00' (which could be the current datetime) can be used.
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The following example shows how the query must be extended to ensure a single supplier record is retrieved for each transaction.
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If relationship is made with surrogate to solve problem above then one ends with entity tied to a specific time slice.
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You can do "as at now", "as at transaction time" or "as at a point in time" queries by changing the date filter logic.
57:
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This method allows more flexible links to the dimension, even if one has used the Type 2 approach instead of Type 6.
255:. Technically, the surrogate key is not necessary, since the row will be unique by the natural key (Supplier_Code).
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which, while generally stable, may change over time, often in an unpredictable manner. This contrasts with a
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For example, if the supplier relocates to Illinois the version numbers will be incremented sequentially:
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If the join query is not written correctly, it may return duplicate rows and/or give incorrect answers.
82:
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For the example below, the original table name is Supplier and the history table is Supplier_History:
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on Product table and using Supplier_Key as foreign key each product is tied on specific time slice.
713:
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To get history records based on a specific date (if more than one date exists in the fact table):
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into the fact table. This allows the user to select the appropriate dimension records based on:
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126:
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If the supplier relocates the headquarters to Illinois the record would be overwritten:
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This method overwrites old with new data, and therefore does not track historical data.
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2315:
2258:
The Data Warehouse Toolkit: The Definitive Guide to Dimensional Modeling, 3rd Edition
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309:
252:
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by DBMS is not possible since there is not a unique key to create the relationship.
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Here is the Supplier table as we created it above using Type 6 Hybrid methodology:
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While more complex, there are a number of advantages of this approach, including:
1682:
Here is the Supplier table as we might have created it using Type 2 methodology:
172:
The challenge with SCDs lies in preserving historical accuracy while maintaining
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dimension tables. SCDs provide mechanisms to manage such changes effectively.
181:
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This method tracks historical data by creating multiple records for a given
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calls this method "Unpredictable Changes with Single-Version Overlay" in
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The Supplier table starts out with one record for our example supplier:
49: in this article. Unsourced material may be challenged and removed.
2215:
The Data Warehouse Toolkit: The Complete Guide to Dimensional Modeling
2126:
530:
The Current_Flag value of 'Y' indicates the current tuple version.
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2489:
2484:
2328:
2243:"Design Tip #152 Slowly Changing Dimension Types 0, 4, 5, 6 and 7"
2229:"Design Tip #152 Slowly Changing Dimension Types 0, 4, 5, 6 and 7"
2125:
138:
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2643:
2370:
2332:
2320:
Kimball University: Handling Arbitrary Restatements of History
2283:"Slowly Changing Dimensions Are Not Always as Easy as 1, 2, 3"
1281:
Here is the Supplier table using the pure Type 6 methodology:
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from the dimension is put into the fact table in place of the
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And a third method uses an effective date and a current flag.
18:
1500:
by DBMS is now possible, but one cannot use Supplier_Code as
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the primary effective date on the fact record (above),
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during a conversation with Stephen Pace from Kalido.
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This method resembles how database audit tables and
201:. Type 0 applies to most date dimension attributes.
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1047:In many Type 2 and Type 6 SCD implementations, the
390:Another method is to add 'effective date' columns.
2110:tools do not handle generating complex joins well.
541:by DBMS (DataBase Management System) impossible.
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1675:any other date associated with the fact record.
1638:Type 7: Hybrid - Both surrogate and natural key
2823:Data warehousing products and their producers
2344:
2281:Ross, Margy; Kimball, Ralph (March 1, 2005).
8:
2256:Kimball, Ralph; Ross, Margy (July 1, 2013).
2260:. John Wiley & Sons, Inc. p. 122.
2103:The date comparison might not perform well.
247:In the above example, Supplier_Code is the
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1653:An alternative implementation is to place
1043:Type 2 surrogate key with type 3 attribute
533:Transactions that reference a particular
109:Learn how and when to remove this message
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308:in the dimensional tables with separate
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1672:the most recent or current information,
1642:- Both surrogate and natural key": -->
7:
47:adding citations to reliable sources
1038:Type 2 / type 6 fact implementation
2708:MultiDimensional eXpressions (MDX)
2308:, US Patent Office, Patent Number
14:
23:
34:needs additional citations for
2729:Business intelligence software
2608:Extract, load, transform (ELT)
2603:Extract, transform, load (ETL)
1:
2677:Decision support system (DSS)
2213:Kimball, Ralph; Ross, Margy.
1629:'2012-01-01T00:00:00'
1611:'2012-01-01T00:00:00'
1521:dates in the dimension table.
212:Example of a supplier table:
16:Structure in data warehousing
2703:Data Mining Extensions (DMX)
2304:Bruce Ottmann, Chris Angus:
2159:Entity–attribute–value model
700:Acme & Johnson Supply Co
645:Acme & Johnson Supply Co
2464:Ensemble modeling patterns
2434:Single version of the truth
2174:Business process management
58:"Slowly changing dimension"
2873:
2818:Comparison of OLAP servers
1269:Pure type 6 implementation
743:The Data Warehouse Toolkit
143:rapidly changing dimension
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2687:Data warehouse automation
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2639:
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2372:Creating a data warehouse
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729:Type 6: combined approach
608:Type 4: add history table
549:Type 3: add new attribute
131:slowly changing dimension
1971:
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1884:To get history records:
1783:
1781:To get current records:
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1370:
1173:
2713:XML for Analysis (XMLA)
575:Current_Supplier_State
569:Original_Supplier_State
189:Type 0: retain original
2645:Using a data warehouse
2500:Operational data store
2306:Data processing system
2287:Intelligent Enterprise
2131:
251:and Supplier_Key is a
147:geographical locations
2662:Business intelligence
2129:
2108:Business Intelligence
2092:Referential integrity
1498:Referential integrity
716:techniques function.
539:referential integrity
199:Original Credit Score
178:referential integrity
2478:Focal point modeling
2450:Column-oriented DBMS
2399:Dimensional modeling
2169:Operational planning
1362:9999-12-31T23:59:59
1342:2008-02-04T00:00:00
1322:2004-12-22T00:00:00
706:2004-12-22T00:00:00
689:2003-06-14T00:00:00
431:2004-12-22T00:00:00
43:improve this article
2783:Information factory
2556:Early-arriving fact
2473:Data vault modeling
2424:Reverse star schema
2312:. February 21, 2006
2144:Change data capture
1772:9999-12-31T23:59:59
1769:2008-02-04T00:00:00
1749:2008-02-04T00:00:00
1746:2004-12-22T00:00:00
1726:2004-12-22T00:00:00
1723:2000-01-01T00:00:00
1359:2008-02-04T00:00:00
1339:2004-12-22T00:00:00
1319:2000-01-01T00:00:00
1161:9999-12-31T23:59:59
1158:2008-02-04T00:00:00
1135:2008-02-04T00:00:00
1132:2004-12-22T00:00:00
1109:2004-12-22T00:00:00
1106:2000-01-01T00:00:00
1028:9999-12-31T23:59:59
1025:2008-02-04T00:00:00
999:2008-02-04T00:00:00
996:2004-12-22T00:00:00
970:2004-12-22T00:00:00
967:2000-01-01T00:00:00
901:9999-12-31T23:59:59
898:2004-12-22T00:00:00
872:2004-12-22T00:00:00
869:2000-01-01T00:00:00
804:9999-12-31T23:59:59
801:2000-01-01T00:00:00
714:change data capture
656:
621:
592:2004-12-22T00:00:00
521:2004-12-22T00:00:00
501:2000-01-01T00:00:00
448:2004-12-22T00:00:00
428:2000-01-01T00:00:00
300:Type 2: add new row
2734:Reporting software
2324:. December 9, 2007
2245:. 5 February 2013.
2231:. 5 February 2013.
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1517:You can introduce
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180:. For instance, a
155:product attributes
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2530:Sixth normal form
2267:978-1-118-53080-1
2149:Temporal database
2130:Scd model example
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205:Type 1: overwrite
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2587:Slowly changing
2577:Dimension table
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2516:Data dictionary
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2468:Anchor modeling
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2122:Combining types
2087:Some cautions:
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1220:
1217:
1214:
1211:
1208:
1205:
1202:
1199:
1196:
1193:
1190:
1187:
1184:
1181:
1178:
1175:
1045:
1040:
731:
722:
634:Supplier_State
610:
551:
451:
302:
273:Supplier_State
227:Supplier_State
207:
191:
123:data management
115:
104:
98:
95:
52:
50:
40:
28:
17:
12:
11:
5:
2870:
2868:
2860:
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2825:
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2814:
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2808:
2807:
2805:
2804:
2799:
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2797:
2795:Enterprise bus
2787:
2786:
2785:
2774:
2772:
2764:
2763:
2760:
2753:
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2326:
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2248:
2234:
2220:
2189:
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2186:
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2176:
2171:
2166:
2161:
2156:
2151:
2146:
2139:
2136:
2123:
2120:
2119:
2118:
2111:
2104:
2101:
2098:
2095:
2007:supplier_state
1972:
1922:supplier_state
1887:
1819:supplier_state
1784:
1777:
1776:
1773:
1770:
1767:
1764:
1763:Acme Supply Co
1761:
1758:
1754:
1753:
1750:
1747:
1744:
1741:
1740:Acme Supply Co
1738:
1735:
1731:
1730:
1727:
1724:
1721:
1718:
1717:Acme Supply Co
1715:
1712:
1708:
1707:
1704:
1701:
1698:
1697:Supplier_State
1695:
1692:
1689:
1677:
1676:
1673:
1670:
1639:
1636:
1554:supplier_state
1531:
1526:
1525:
1522:
1515:
1511:
1508:
1505:
1394:supplier_state
1371:
1364:
1363:
1360:
1357:
1354:
1353:Acme Supply Co
1351:
1348:
1344:
1343:
1340:
1337:
1334:
1333:Acme Supply Co
1331:
1328:
1324:
1323:
1320:
1317:
1314:
1313:Acme Supply Co
1311:
1308:
1304:
1303:
1300:
1297:
1296:Supplier_State
1294:
1291:
1288:
1270:
1267:
1174:
1166:
1165:
1162:
1159:
1156:
1153:
1150:
1149:Acme Supply Co
1147:
1144:
1140:
1139:
1136:
1133:
1130:
1127:
1124:
1123:Acme Supply Co
1121:
1118:
1114:
1113:
1110:
1107:
1104:
1101:
1098:
1097:Acme Supply Co
1095:
1092:
1088:
1087:
1084:
1081:
1078:
1075:
1072:
1069:
1066:
1044:
1041:
1039:
1036:
1033:
1032:
1029:
1026:
1023:
1020:
1017:
1016:Acme Supply Co
1014:
1011:
1008:
1004:
1003:
1000:
997:
994:
991:
988:
987:Acme Supply Co
985:
982:
979:
975:
974:
971:
968:
965:
962:
959:
958:Acme Supply Co
956:
953:
950:
946:
945:
942:
939:
936:
933:
930:
927:
924:
921:
906:
905:
902:
899:
896:
893:
890:
889:Acme Supply Co
887:
884:
881:
877:
876:
873:
870:
867:
864:
861:
860:Acme Supply Co
858:
855:
852:
848:
847:
844:
841:
838:
835:
832:
829:
826:
823:
809:
808:
805:
802:
799:
796:
793:
792:Acme Supply Co
790:
787:
784:
780:
779:
776:
773:
770:
767:
764:
761:
758:
755:
730:
727:
721:
718:
708:
707:
704:
701:
698:
695:
691:
690:
687:
684:
683:Acme Supply Co
681:
678:
674:
673:
670:
669:Supplier_State
667:
664:
661:
650:
649:
646:
643:
640:
636:
635:
632:
629:
626:
609:
606:
597:
596:
593:
590:
587:
586:Acme Supply Co
584:
581:
577:
576:
573:
572:Effective_Date
570:
567:
564:
561:
550:
547:
526:
525:
522:
519:
516:
515:Acme Supply Co
513:
510:
506:
505:
502:
499:
496:
495:Acme Supply Co
493:
490:
486:
485:
482:
481:Effective_Date
479:
478:Supplier_State
476:
473:
470:
455:
454:
449:
446:
443:
442:Acme Supply Co
440:
437:
433:
432:
429:
426:
423:
422:Acme Supply Co
420:
417:
413:
412:
409:
406:
405:Supplier_State
403:
400:
397:
386:
385:
382:
379:
378:Acme Supply Co
376:
373:
369:
368:
365:
362:
361:Acme Supply Co
359:
356:
352:
351:
348:
345:
344:Acme Supply Co
342:
339:
335:
334:
331:
330:Supplier_State
328:
325:
322:
310:surrogate keys
301:
298:
289:
288:
285:
284:Acme Supply Co
282:
279:
275:
274:
271:
268:
265:
243:
242:
239:
238:Acme Supply Co
236:
233:
229:
228:
225:
222:
219:
206:
203:
190:
187:
174:data integrity
117:
116:
31:
29:
22:
15:
13:
10:
9:
6:
4:
3:
2:
2869:
2858:
2855:
2853:
2852:Data modeling
2850:
2849:
2847:
2824:
2821:
2819:
2816:
2815:
2813:
2809:
2803:
2800:
2796:
2793:
2792:
2791:
2790:Ralph Kimball
2788:
2784:
2781:
2780:
2779:
2776:
2775:
2773:
2769:
2765:
2758:
2754:
2740:
2737:
2735:
2732:
2730:
2727:
2726:
2724:
2720:
2714:
2711:
2709:
2706:
2704:
2701:
2700:
2698:
2694:
2688:
2685:
2683:
2680:
2678:
2675:
2673:
2670:
2668:
2665:
2663:
2660:
2659:
2657:
2653:
2649:
2642:
2638:
2624:
2621:
2619:
2616:
2614:
2611:
2609:
2606:
2604:
2601:
2600:
2598:
2594:
2588:
2585:
2583:
2580:
2578:
2575:
2574:
2572:
2568:
2562:
2559:
2557:
2554:
2552:
2549:
2548:
2546:
2542:
2536:
2535:Surrogate key
2533:
2531:
2528:
2526:
2523:
2521:
2517:
2514:
2513:
2511:
2507:
2501:
2498:
2496:
2493:
2491:
2488:
2486:
2483:
2479:
2476:
2474:
2471:
2469:
2466:
2465:
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2456:
2453:
2451:
2448:
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2441:
2435:
2432:
2430:
2427:
2425:
2422:
2420:
2417:
2415:
2412:
2410:
2407:
2405:
2402:
2400:
2397:
2395:
2392:
2390:
2387:
2386:
2384:
2380:
2376:
2369:
2365:
2361:
2354:
2349:
2347:
2342:
2340:
2335:
2334:
2331:
2323:
2321:
2317:
2316:Ralph Kimball
2314:
2311:
2307:
2303:
2302:
2297:
2288:
2284:
2277:
2274:
2269:
2263:
2259:
2252:
2249:
2244:
2238:
2235:
2230:
2224:
2221:
2216:
2209:
2207:
2205:
2203:
2201:
2199:
2197:
2195:
2191:
2184:
2180:
2177:
2175:
2172:
2170:
2167:
2165:
2162:
2160:
2157:
2155:
2152:
2150:
2147:
2145:
2142:
2141:
2137:
2135:
2128:
2121:
2116:
2112:
2109:
2105:
2102:
2099:
2096:
2093:
2090:
2089:
2088:
2058:delivery_date
2046:supplier_code
2034:supplier_code
1995:supplier_name
1983:delivery_cost
1970:
1961:supplier_code
1949:supplier_code
1910:supplier_name
1898:delivery_cost
1885:
1858:supplier_code
1846:supplier_code
1807:supplier_name
1795:delivery_cost
1782:
1774:
1771:
1768:
1765:
1762:
1759:
1756:
1755:
1751:
1748:
1745:
1742:
1739:
1736:
1733:
1732:
1728:
1725:
1722:
1719:
1716:
1713:
1710:
1709:
1706:Current_Flag
1705:
1702:
1699:
1696:
1694:Supplier_Name
1693:
1691:Supplier_Code
1690:
1687:
1686:
1683:
1680:
1674:
1671:
1668:
1667:
1666:
1664:
1660:
1659:surrogate key
1656:
1646:
1637:
1542:supplier_code
1529:
1523:
1520:
1516:
1512:
1509:
1506:
1503:
1499:
1496:
1495:
1494:
1491:
1469:delivery_date
1445:delivery_date
1382:supplier_code
1369:
1361:
1358:
1355:
1352:
1349:
1346:
1345:
1341:
1338:
1335:
1332:
1329:
1326:
1325:
1321:
1318:
1315:
1312:
1309:
1306:
1305:
1301:
1298:
1295:
1293:Supplier_Name
1292:
1290:Supplier_Code
1289:
1286:
1285:
1282:
1279:
1276:
1268:
1221:current_state
1197:supplier_name
1185:delivery_cost
1172:
1163:
1160:
1157:
1154:
1151:
1148:
1145:
1142:
1141:
1137:
1134:
1131:
1128:
1125:
1122:
1119:
1116:
1115:
1111:
1108:
1105:
1102:
1099:
1096:
1093:
1090:
1089:
1086:Current_Flag
1085:
1082:
1079:
1076:
1074:Current_State
1073:
1071:Supplier_Name
1070:
1068:Supplier_Code
1067:
1064:
1063:
1060:
1057:
1054:
1050:
1049:surrogate key
1042:
1037:
1030:
1027:
1024:
1021:
1018:
1015:
1012:
1009:
1006:
1005:
1001:
998:
995:
992:
989:
986:
983:
980:
977:
976:
972:
969:
966:
963:
960:
957:
954:
951:
948:
947:
944:Current_Flag
943:
940:
937:
934:
932:Current_State
931:
929:Supplier_Name
928:
926:Supplier_Code
925:
922:
919:
918:
915:
912:
903:
900:
897:
894:
891:
888:
885:
882:
879:
878:
874:
871:
868:
865:
862:
859:
856:
853:
850:
849:
846:Current_Flag
845:
842:
839:
836:
834:Current_State
833:
831:Supplier_Name
830:
828:Supplier_Code
827:
824:
821:
820:
817:
814:
806:
803:
800:
797:
794:
791:
788:
785:
782:
781:
778:Current_Flag
777:
774:
771:
768:
766:Current_State
765:
763:Supplier_Name
762:
760:Supplier_Code
759:
756:
753:
752:
749:
746:
744:
740:
739:Ralph Kimball
736:
735:Ralph Kimball
728:
726:
719:
717:
715:
705:
702:
699:
696:
693:
692:
688:
685:
682:
679:
676:
675:
671:
668:
666:Supplier_Name
665:
663:Supplier_Code
662:
659:
658:
647:
644:
641:
638:
637:
633:
631:Supplier_Name
630:
628:Supplier_Code
627:
624:
623:
617:
614:
607:
605:
602:
594:
591:
588:
585:
582:
579:
578:
574:
571:
568:
566:Supplier_Name
565:
563:Supplier_Code
562:
559:
558:
555:
548:
546:
542:
540:
536:
535:surrogate key
531:
523:
520:
517:
514:
511:
508:
507:
503:
500:
497:
494:
491:
488:
487:
484:Current_Flag
483:
480:
477:
475:Supplier_Name
474:
472:Supplier_Code
471:
468:
467:
464:
461:
450:
447:
444:
441:
438:
435:
434:
430:
427:
424:
421:
418:
415:
414:
410:
407:
404:
402:Supplier_Name
401:
399:Supplier_Code
398:
395:
394:
391:
383:
380:
377:
374:
371:
370:
366:
363:
360:
357:
354:
353:
349:
346:
343:
340:
337:
336:
332:
329:
327:Supplier_Name
326:
324:Supplier_Code
323:
320:
319:
316:
313:
311:
307:
299:
297:
294:
286:
283:
280:
277:
276:
272:
270:Supplier_Name
269:
267:Supplier_Code
266:
263:
262:
259:
256:
254:
253:surrogate key
250:
240:
237:
234:
231:
230:
226:
224:Supplier_Name
223:
221:Supplier_Code
220:
217:
216:
213:
210:
204:
202:
200:
196:
195:Date of Birth
188:
186:
183:
179:
175:
170:
168:
164:
158:
156:
152:
148:
144:
140:
136:
132:
128:
124:
113:
110:
102:
91:
88:
84:
81:
77:
74:
70:
67:
63:
60: –
59:
55:
54:Find sources:
48:
44:
38:
37:
32:This article
30:
26:
21:
20:
2802:Dan Linstedt
2586:
2319:
2305:
2286:
2276:
2257:
2251:
2237:
2223:
2214:
2179:Data element
2164:Multitenancy
2133:
2086:
1968:
1883:
1870:current_flag
1780:
1688:Supplier_Key
1681:
1678:
1654:
1652:
1593:supplier_key
1581:supplier_key
1527:
1492:
1488:
1433:supplier_key
1421:supplier_key
1367:
1287:Supplier_Key
1280:
1272:
1260:supplier_key
1248:supplier_key
1169:
1065:Supplier_Key
1058:
1046:
920:Supplier_Key
913:
911:processing.
909:
822:Supplier_Key
815:
812:
754:Supplier_Key
747:
742:
732:
723:
711:
672:Create_Date
660:Supplier_Key
625:Supplier_Key
615:
611:
603:
600:
560:Supplier_Key
552:
543:
532:
529:
469:Supplier_Key
462:
458:
396:Supplier_Key
389:
321:Supplier_Key
314:
303:
295:
292:
264:Supplier_Key
257:
246:
218:Supplier_Key
211:
208:
198:
194:
192:
171:
159:
142:
137:that stores
130:
120:
105:
96:
86:
79:
72:
65:
53:
41:Please help
36:verification
33:
2739:Spreadsheet
2672:Data mining
2414:Star schema
2154:Log trigger
1876:'Y'
1663:natural key
1519:bi-temporal
1502:foreign key
1275:master data
1053:natural key
306:natural key
249:natural key
133:(SCD) is a
2846:Categories
2778:Bill Inmon
2582:Degenerate
2551:Fact table
2298:References
2070:Start_Date
1700:Start_Date
1605:start_date
1457:start_date
1299:Start_Date
1080:Start_Date
938:Start_Date
840:Start_Date
772:Start_Date
408:Start_Date
182:fact table
163:analytical
99:March 2015
69:newspapers
2696:Languages
2682:OLAP cube
2667:Dashboard
2618:Transform
2570:Dimension
2525:Data mart
2460:Data mesh
2429:Aggregate
2394:Dimension
2310:7,003,504
1302:End_Date
620:Supplier
411:End_Date
167:reporting
135:dimension
2811:Products
2655:Concepts
2520:Metadata
2509:Elements
2455:Data hub
2443:Variants
2389:Database
2382:Concepts
2138:See also
2082:End_Date
2076:supplier
2064:supplier
2052:delivery
2040:supplier
2028:delivery
2022:supplier
2013:delivery
2001:supplier
1989:supplier
1977:delivery
1955:supplier
1943:delivery
1937:supplier
1928:delivery
1916:supplier
1904:supplier
1892:delivery
1864:supplier
1852:supplier
1840:delivery
1834:supplier
1825:delivery
1813:supplier
1801:supplier
1789:delivery
1703:End_Date
1661:and the
1623:end_date
1617:supplier
1599:supplier
1587:delivery
1575:supplier
1569:delivery
1560:supplier
1548:supplier
1536:supplier
1514:easily).
1481:end_date
1475:supplier
1463:delivery
1451:supplier
1439:delivery
1427:delivery
1415:supplier
1409:delivery
1400:supplier
1388:supplier
1376:supplier
1254:supplier
1242:delivery
1236:supplier
1227:delivery
1215:supplier
1203:supplier
1191:supplier
1179:delivery
1083:End_Date
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