Query development experience 2

If any record is reproduced, declare the Source: http://blog.csdn.net/donkey2004425103/archive/2009/02/26/3939821.aspx.

The query contains four filters, including free attributes, rows, and columns.

• 1. Differences between free features and filters

I think it is a way of looking at data. The first two filters and free characteristics are used to filter data globally, but the filter has a higher priority, each cell is limited by its own. If it is a free feature, if it has other restrictions, it will not consider the restrictions of the free feature. For example, there is a limitation on the fiscal year in the free feature. By default, if there is a number of years in the column, you add a limit on the previous year. In this case, this column has a higher priority. However, the conditions in the filter are still valid. These two conditions should be of a higher priority.

Another obvious difference is that the variables in the free feature are used as the input interface for selecting the screen. The reason for this is that the free feature is actually a dynamic filtering, and the filter is a static filtering. For example, if I want to find a person with three years of SAP experience, in the past three years, it has been a static one. Dynamic screening is a screening that is not a fixed value. For example, I am looking for a consultant with a salary higher than the average wage in Beijing, so this is a dynamic screening, because the average salary is not a constant value and is always changing.

• 2. rows and columns

In the query, the rows and columns are the key values and dimensions in the relative model. The columns make us want the data and the rows let us see the data dimension.

Query is convenient for data with relatively unified data, but sometimes it is very troublesome to define many custom cells. It is expected that secondary development can be performed in the query in the future, just like the Excel VBA, which may be more convenient. I have not created my own models yet, so I hope to have a deeper understanding of what is at the bottom of BW.