Journal of Cybersecurity and Information Management

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Volume 17 , Issue 2 , PP: 146-166, 2026 | Cite this article as | XML | Html | PDF | Full Length Article

Vector Search in Large Language Models: Experimental Evaluation with MongoDB Atlas

Deepak 1 * , Savita Sheoran 2

  • 1 Department of Computer Science & Engineering, Indira Gandhi University, Meerpur Rewari, India - (dpkrao91@gmail.com)
  • 2 Department of Computer Science & Engineering, Indira Gandhi University, Meerpur Rewari, India - (savita.sheoran@igu.ac.in)
  • Doi: https://doi.org/10.54216/JCIM.170211

    Received: April 10, 2025 Revised: June 23, 2025 Accepted: August 17, 2025
    Abstract

    The growth of Large Language Models (LLMs) applications has intensified the demand for efficient vector database solutions capable of handling high-dimensional semantic search operations. Contemporary information retrieval systems face significant challenges in processing complex queries across vast knowledge repositories while maintaining contextual accuracy and computational efficiency. This research investigates the optimization potential of vector search implementations in LLMs through comprehensive evaluation using MongoDB Atlas as the primary vector database platform. Traditional keyword-based retrieval methods fail to capture semantic relationships and contextual nuances essential for accurate information extraction in modern AI applications. Vector-based query optimization enables semantic similarity matching, allowing systems to access contextually relevant data or information even when exact keyword matches are absent. But it significantly improving response quality and user experience. The study addresses critical performance bottlenecks in production-scale vector search deployments, where query latency and retrieval accuracy directly impact system usability. Through systematic comparison of traditional text-embedding-ada-002 against the advanced text-embedding-3-small model, we demonstrate substantial performance enhancements across multiple evaluation metrics. Results establish text-embedding-3-small as superior for semantic search applications, while GPT-4o-mini demonstrates optimal faithfulness performance (0.9067) for accuracy-critical deployments.

    Keywords :

    Vector Search , Large Language Models , MongoDB Atlas , Semantic Search , Natural Language Processing , Vector Databases , Embedding Models

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    Cite This Article As :
    , Deepak. , Sheoran, Savita. Vector Search in Large Language Models: Experimental Evaluation with MongoDB Atlas. Journal of Cybersecurity and Information Management, vol. , no. , 2026, pp. 146-166. DOI: https://doi.org/10.54216/JCIM.170211
    , D. Sheoran, S. (2026). Vector Search in Large Language Models: Experimental Evaluation with MongoDB Atlas. Journal of Cybersecurity and Information Management, (), 146-166. DOI: https://doi.org/10.54216/JCIM.170211
    , Deepak. Sheoran, Savita. Vector Search in Large Language Models: Experimental Evaluation with MongoDB Atlas. Journal of Cybersecurity and Information Management , no. (2026): 146-166. DOI: https://doi.org/10.54216/JCIM.170211
    , D. , Sheoran, S. (2026) . Vector Search in Large Language Models: Experimental Evaluation with MongoDB Atlas. Journal of Cybersecurity and Information Management , () , 146-166 . DOI: https://doi.org/10.54216/JCIM.170211
    D. , Sheoran S. [2026]. Vector Search in Large Language Models: Experimental Evaluation with MongoDB Atlas. Journal of Cybersecurity and Information Management. (): 146-166. DOI: https://doi.org/10.54216/JCIM.170211
    , D. Sheoran, S. "Vector Search in Large Language Models: Experimental Evaluation with MongoDB Atlas," Journal of Cybersecurity and Information Management, vol. , no. , pp. 146-166, 2026. DOI: https://doi.org/10.54216/JCIM.170211