DP-900 Describe core data concepts Practice Question
A company stores customer orders in a database. Each order has an OrderID (integer), CustomerName (text), OrderDate (date), and a JSON column for order details that contains varying fields such as discount codes or gift messages. Which statement best describes the data types in this table?
⚠ Common exam trap
The trap here is that candidates often mistake JSON for unstructured data, but JSON is semi-structured because it has a logical structure (key-value pairs) even though the schema is flexible, leading them to incorrectly choose option C.
Answer choices
Why each option matters
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
The table stores both structured and semi-structured data.
The table includes structured columns (OrderID integer, CustomerName text, OrderDate date) and a JSON column for order details, which stores semi-structured data because JSON allows flexible schemas with varying fields like discount codes or gift messages. This combination of fixed-schema columns and a schema-less JSON column means the table holds both structured and semi-structured data, making option B correct.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✗
The table stores only structured data.
Why it's wrong here
Although the fixed columns (OrderID, CustomerName, OrderDate) are classic structured relational data, the presence of an OrdersJSON column means each row can carry varying fields, nested objects, and arrays. That flexibility is the defining characteristic of semi-structured data. Because the table includes this JSON column, it cannot be described as containing only structured data; it also holds semi-structured data.
- ✓
The table stores both structured and semi-structured data.
Why this is correct
The OrderID, CustomerName, and OrderDate columns have fixed data types and enforce a rigid schema, exactly fitting the structured category. In contrast, the JSON column stores order details that can differ per customer order, such as optional fields or nested line items, which is typical of semi-structured data. A single table can therefore mix both categories, and that is precisely what this design does.
- ✗
The table stores only unstructured data.
Why it's wrong here
Unstructured data has no predefined organizational structure, such as raw text, images, or video, and cannot be easily stored in rows and columns. This table clearly defines columns with data types, and every order occupies a row, so the data is placed into a fixed schema. Therefore the table is the opposite of unstructured; it is primarily relational, with an additional semi-structured JSON column.
- ✗
The table stores only semi-structured data.
Why it's wrong here
The three fixed columns are strongly typed and do not permit per-row schema variation, so they are definitely structured data, not semi-structured. Semi-structured data, like the JSON column, does not require all rows to have the same fields, but it coexists here with a rigid relational schema. Thus the table is a hybrid, not purely semi-structured.
Go deeper
Related to this question
Learn chapter
Data Roles and Core Concepts
Key term
Column
A column is a vertical set of values in a database table that stores one specific type of attribute for every row.
Key term
Schema
A schema is a blueprint or logical structure that defines how data is organized, stored, and accessed in a database or information system.
About these practice questions
Courseiva writes every DP-900 question from scratch — 820 in total, each with an explanation and a wrong-answer breakdown. None are copied from real exams or dumps. Learn why practice questions differ from exam dumps →
JA
Written by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
This DP-900 practice question is part of Courseiva's free Microsoft certification practice question bank. Courseiva provides original exam-style practice questions with explanations, topic-based practice, mock exams, readiness tracking, and study analytics to help learners prepare for the DP-900 exam.