Software architecture is commonly defined in terms of components. and almost all softwares contains database components as well as buisiness components. database being the databearer should have a good data model and design and will be well fine tuned by dba or other experts in database concepts
One of the Axioms from Scott's Axioms of Programmings says
Writing more code leads to more bugs, which leads to a longer development cycle, which leads to higher costs. Therefore, a minimalistic approach should be taken to writing code