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Anderson Sinaluisa
Anderson Sinaluisa

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Building an AI tool that generates SQL queries from natural language

The problem

Writing SQL queries is something most developers do frequently, but it can still be slow and repetitive.

Sometimes you just want to ask something simple like:

"show users created this month"

Instead of switching context, checking the schema, and writing the query manually.

I started experimenting with an idea:

What if you could generate SQL queries using natural language?


The idea

The goal was simple:

Describe the query in plain English and automatically generate the SQL.

Example:

Input:

show users created this month

Output:

SELECT *
FROM users
WHERE created_at >= DATE_TRUNC('month', CURRENT_DATE);

The idea is not to replace developers, but to make it faster to:

  • explore databases
  • generate queries quickly
  • understand complex SQL

Challenges

While experimenting with this approach, I ran into several interesting problems.

Schema understanding

The model needs to understand:

  • tables
  • relationships
  • column names

Without that context, the generated SQL can be incorrect.


Complex joins

Queries involving multiple tables are much harder.

For example:

  • join conditions
  • nested queries
  • aggregations

These require much more context.


Ambiguous column names

Many databases have columns like:

  • id
  • name
  • created_at

Without schema awareness, it becomes difficult to determine the correct table.


The experiment

To explore this idea further, I built a small prototype that generates SQL queries from natural language prompts.

You can try it here:

https://chatsql.andersonsinaluisa.com

It can also:

  • explain complex SQL queries
  • help explore database structures
  • assist with query generation

I'm curious about your thoughts

Do you think tools like this can realistically fit into a developer workflow?

Or are they mainly useful for simple queries?

I'd love to hear your feedback.

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