SQL to NoSQL Converter

SQL to NoSQL Converter — What It Does

Paste a SQL query and select your target NoSQL database — MongoDB or DynamoDB — to get equivalent NoSQL syntax. Handles SELECT, INSERT, UPDATE, and DELETE with WHERE conditions, ORDER BY, and LIMIT clauses. Useful when migrating from a relational database, learning NoSQL query patterns, or quickly prototyping document database queries without memorizing the API.

SQL to MongoDB Quick Reference

• SELECT * → 'db.collection.find({})'
• WHERE x = 1 → 'find({ x: 1 })'
• WHERE x > 5 → 'find({ x: { $gt: 5 } })'
• INSERT INTO → 'insertOne({ ... })'
• UPDATE SET → 'updateMany({}, { $set: { ... } })'
• DELETE FROM → 'deleteMany({ ... })'
• ORDER BY x DESC → '.sort({ x: -1 })'
• LIMIT 10 → .limit(10)

MongoDB Comparison Operators

• $eq — equal, $ne — not equal
• $gt / $gte — greater than / greater than or equal
• $lt / $lte — less than / less than or equal
• $in — matches any value in array (like SQL IN)
• $regex — pattern match (like SQL LIKE)
• $exists: false — field is null or missing (like SQL IS NULL)

NoSQL Migration Tips

• Design for access patterns — Model your data around how it will be queried, not around normalization.
• Embed over reference — If you always load a user with their addresses, embed addresses in the user document.
• Avoid full-collection scans — In DynamoDB, FilterExpression on a Scan reads every item. Always query via the partition key when possible.
• Use indexes strategically — MongoDB secondary indexes and DynamoDB GSIs (Global Secondary Indexes) enable efficient non-key lookups.

Frequently Asked Questions

How does a SQL SELECT query map to MongoDB?

SELECT maps to find() in MongoDB. SELECT * FROM users becomes db.users.find({}). A WHERE clause becomes the filter document: WHERE age > 30 becomes db.users.find({ age: { $gt: 30 } }). Column lists map to projection: SELECT name, email becomes db.users.find({}, { name: 1, email: 1 }).

How does a SQL WHERE clause convert to DynamoDB?

DynamoDB uses a FilterExpression for scan operations and a KeyConditionExpression for queries. WHERE id = :id maps to a KeyConditionExpression when id is the partition key. WHERE status = "active" maps to FilterExpression when status is a non-key attribute, which requires a Scan (less efficient).

Can I convert SQL JOINs to NoSQL?

Not directly — JOIN is a relational concept with no native equivalent in MongoDB or DynamoDB. The NoSQL approach is to embed related data (denormalization) or use application-level joins via multiple queries. This converter handles single-table operations; JOIN conversion requires schema redesign.

What SQL operations does this converter support?

The converter supports SELECT (with WHERE, ORDER BY, LIMIT), INSERT, UPDATE (with SET and WHERE), and DELETE (with WHERE). Conditions support =, !=, >, <, >=, <=, LIKE, IN, and IS NULL operators.

Why are NoSQL query patterns different from SQL?

SQL databases are optimized for flexible ad-hoc queries across normalized data using indexes. NoSQL databases like MongoDB and DynamoDB are optimized for specific, known access patterns with denormalized data. The same data model that works in SQL often requires significant restructuring for efficient NoSQL queries.