Object Relational Impedance Mismatch (ORIM) is also known as

paradigm mismatch. It means that Object model and Relational

model do not work well with each other.

Relational model or a RDBMS represents data in tabular format

like a spreadsheet. Object model or OOPS represents the data as an

inter-connected graph of objects.

Mixing these two models leads to various problems. The common

name for these issues is Object Relational Impedance Mismatch.

https://medium.com/booleanbhushan/object-relational-impedance-mismatch-28fc2440dee4