Many tables associating with the same key

[songguozh]

Hi, can anyone give an opinion on this style of data model? Many tables are associated with the same key/field.  Will this slow down the performance of the system? Thank you very much!

[marcus_sommer · Accepted solution]

Like always - it will depend on the kind of data, the size of the data-set and the requirements of the views.

Beside of this I would regard such kind of data-model as rather unsuitable - from a performance point of view as well as to the efforts and difficulties to create a valid data-model and accessing the data within the UI.

There are various reasons for my opinion:

• efforts to create the key (probably per combining of several fields)
• the size of keys (usually large strings with a lot of distinct field-values)
• even if multiple fields are included within the key not all necessary/valid association may be possible
• missing key-values in one or several tables
• associating from common dimension-tables without ending in circular references and/or synthetic key and/or duplication of fields and/or using different field-names for the same kind of information
• a rather slow UI performance