C100DEV Indexing Practice Question
A developer wants to implement full-text search on a collection of articles. They create a text index on the 'content' field. Which of the following is a significant limitation of 'text' indexes in MongoDB?
⚠ Common exam trap
Test-takers often assume multiple text indexes can be created on different fields across a single collection to handle separate search requirements.
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
✓
A collection can have at most one 'text' index.
A collection in MongoDB can have at most one text index. However, this single index can cover multiple fields by creating a compound text index. This limitation means developers must carefully plan which fields need to be searchable via text commands and consolidate them into a single index definition for that collection.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✗
Text indexes do not support case-insensitive searches.
Why it's wrong here
Text indexes in MongoDB are designed to be case-insensitive by default (for the Roman alphabet). They also handle stop words and stemming, making them more powerful than standard string matches. The limitation of text indexes is usually related to their quantity per collection or their performance, not case sensitivity.
- ✓
A collection can have at most one 'text' index.
Why this is correct
MongoDB restricts each collection to a single text index. To search across multiple fields, you must include all those fields in a single compound text index. This design ensures that the $text operator has a single, unambiguous index to use when executing full-text search queries.
- ✗
Text indexes cannot be used in a sharded cluster.
Why it's wrong here
Text indexes are supported in sharded clusters, but they have specific requirements. For instance, the $text operator is supported, but the shard key cannot be part of the text index itself. They are a valid tool for scaling full-text search capabilities across multiple nodes in a MongoDB environment.
- ✗
You cannot use 'text' indexes with the $match operator in aggregation.
Why it's wrong here
The $text operator is fully supported within the $match stage of an aggregation pipeline, provided it is the first stage in the pipeline. This allows developers to combine the power of full-text search with the complex data transformation capabilities of the MongoDB Aggregation Framework.
About these practice questions
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JA
Written and reviewed by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
Last reviewed September 2026 · checked against the official MongoDB exam blueprint
This C100DEV practice question is part of Courseiva's free MongoDB 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 C100DEV exam.