# Couchbase vs PostgreSQL: which do AI models recommend for nosql, October 2026

IT AI Recommendation Index, October 2026 Edition, NoSQL databases. Zero of fourteen models named Couchbase first on the direct prompt; zero named PostgreSQL. Page: https://it-ai-index.com/it-data/nosql-databases/couchbase-vs-postgresql/

| | First-choice share | Rank | Negative rate | Labels | Models naming it |
|---|---|---|---|---|---|
| Couchbase | 4% | #3 of 13 | 9% | 43 | 14 of 14 |
| PostgreSQL | 2% | #6 of 13 | 0% | 11 | 9 of 14 |

## The direct prompt, model by model

- Gemini 3.5 Flash: neither first, one named (first choices: MongoDB) (alternatives: Amazon DynamoDB, Couchbase)
- DeepSeek V4 Flash: neither first, one named (first choices: MongoDB) (alternatives: Amazon DynamoDB, PostgreSQL)
- Qwen 3.7 Flash: neither first, one named (first choices: MongoDB) (alternatives: Amazon DynamoDB, Neo4j, PostgreSQL)
- Kimi K2: neither first, one named (first choices: MongoDB) (alternatives: Couchbase)
- GLM 4.7 FlashX: neither first, one named (first choices: MongoDB) (alternatives: Amazon DynamoDB, Apache Cassandra, Couchbase)
- MiniMax M2.5: neither first, one named (first choices: MongoDB) (alternatives: Amazon DynamoDB, Couchbase)
- GPT-6 Luna: neither first, one named (first choices: MongoDB) (alternatives: Amazon DynamoDB, PostgreSQL)
- Claude Haiku 4.5: neither named (first choices: MongoDB) (alternatives: Amazon DynamoDB, Google Cloud Firestore, PostgreSQL with JSON)
- GPT-5.4 mini: neither named (first choices: MongoDB) (alternatives: Amazon DynamoDB, Apache Cassandra)
- Perplexity Sonar: neither named (first choices: MongoDB) (alternatives: Amazon DynamoDB, Azure Cosmos DB)
- Grok 4.1 Fast: neither named (first choices: MongoDB) (alternatives: Amazon DynamoDB, Apache Cassandra)
- Mistral Small: neither named (first choices: Amazon DynamoDB, MongoDB) (alternatives: Azure Cosmos DB, Redis)
- Llama 4 Maverick: neither named (first choices: MongoDB)
- Muse Glimmer 30B: neither named (first choices: MongoDB) (alternatives: Amazon DynamoDB)

## What the models said about Couchbase

- "otherwise it is usually more specialized than MongoDB for a general mid-market B2B stack" (GPT-5.4 mini, direct prompt, soft negative)
- "Cons: Heavier operational complexity compared to fully managed alternatives" (DeepSeek V4 Flash, paraphrase prompt, soft negative)
- "More enterprise-focused, $1,800+/mo — likely overkill for mid-market" (DeepSeek V4 Flash, direct prompt, soft negative)
- "1. Couchbase - a key-value database that stores data as documents, ideal for simple data storage and retrieval needs." (Llama 4 Maverick, paraphrase prompt, first choice)
- "MongoDB and Couchbase are the best choices due to their ease of use, strong community support, and free tiers" (Mistral Small, budget prompt, first choice)
- "Prefer managed services to keep ops headcount low: MongoDB Atlas, Amazon DynamoDB, Azure Cosmos DB, Couchbase Capella, managed Cassandra." (Muse Glimmer 30B, scale prompt, alternative)

## What the models said about PostgreSQL

- "Before choosing any NoSQL database, ask yourself: "Why can't I use PostgreSQL?"" (Gemini 3.5 Flash, negative prompt, first choice)
- "If your data is highly normalized and relational ... stick to Postgres." (Qwen 3.7 Flash, scale prompt, first choice)
- "modern trends suggest looking at PostgreSQL (specifically with JSONB) as the ultimate hybrid solution" (Qwen 3.7 Flash, direct prompt, alternative)

Share is the count of first choices across the direct, paraphrase, budget and scale prompts over all fourteen models, for a mid-market B2B company; rank is within the category. Comparisons are drawn for the top eight products in each category. Published under CC BY 4.0; the output is the models' output, and nothing here is a recommendation by the index.