| By using a data warehouse you are in effect | | | | systems. This means that they can perform retrieval |
| providing a common data model for all data that is of | | | | of data operation without interfering with any |
| interest without having to be concerned about the | | | | operational requirement of the system. |
| origin of the source. This ability makes it far easier to | | | | Data warehouses is also able to work in conjunction |
| compile a report and analyse all available information | | | | with, and by doing so enhance the value of, |
| than it would be if you had to retrieve information m | | | | operational business applications, the most notable of |
| invoices, ledgers orders and so on from a multitude | | | | which being customer relationship management (CRM) |
| of data models. | | | | systems. |
| Before the data is loaded into the data warehouse it | | | | Data warehouses are generally used to facilitate |
| has to be cleansed, in effect this involves identifying | | | | applications associated within the decision support |
| and resolving all the dirty/inconsistent data. By doing | | | | system. These applications will deal with reports |
| this before the data is loaded into the data | | | | concerning trends, for example what was item had |
| warehouse the actions of reporting and analysing | | | | the best sales in what area over the last year, |
| data are greatly simplified. | | | | exception reports, and reports that show actual |
| Once it has been loaded into the data warehouse the | | | | performance versus goals. |
| information is under the control of the user. This | | | | The ability of data warehousing to compile, analyse |
| allows for the information in the warehouse to be | | | | and report information from different sources to give |
| stored safely for extended periods of time, even if | | | | valuable information quickly rather than trawl through |
| the source system data is purged over time, | | | | information from different sources in different |
| Another great advantage of using a data warehouse | | | | formats is priceless in this age of instant decision |
| is that they are separate from any operational | | | | making. |