query-builder

Convert natural language questions into SQL queries using the database schema.

When to Use

Activate when user asks questions like:

• "Show me all users who signed up last month"
• "Find orders greater than $100"
• "Which products have low inventory?"
• "Get the top 10 customers by total spend"

Workflow

1. Understand the Schema

Before generating SQL, always check the table structure:

whodb_tables(connection="...") → Get available tables
whodb_columns(table="relevant_table") → Get column names and types

2. Identify Intent

Parse the natural language request:

• Subject: What entity? (users, orders, products)
• Filter: What conditions? (last month, > $100, active)
• Aggregation: Count, sum, average, max, min?
• Grouping: By what dimension?
• Ordering: Sort by what? Ascending/descending?
• Limit: How many results?

3. Map to Schema

• Match entities to table names
• Match attributes to column names
• Identify foreign key joins needed

4. Generate SQL

Build the query following SQL best practices:

SELECT columns
FROM table
[JOIN other_table ON condition]
WHERE filters
[GROUP BY columns]
[HAVING aggregate_condition]
ORDER BY column [ASC|DESC]
LIMIT n;

5. Execute and Present

whodb_query(query="generated SQL")

Translation Patterns

| Natural Language | SQL Pattern | |------------------|-------------| | "last week/month/year" | WHERE date_col >= DATE_SUB(NOW(), INTERVAL 1 WEEK) | | "more than X" / "greater than X" | WHERE col > X | | "top N" | ORDER BY col DESC LIMIT N | | "how many" | SELECT COUNT(*) | | "total" / "sum of" | SELECT SUM(col) | | "average" | SELECT AVG(col) | | "for each" / "by" | GROUP BY col | | "between X and Y" | WHERE col BETWEEN X AND Y | | "contains" / "like" | WHERE col LIKE '%term%' | | "starts with" | WHERE col LIKE 'term%' | | "is empty" / "is null" | WHERE col IS NULL | | "is not empty" | WHERE col IS NOT NULL |

Date Handling by Database

PostgreSQL

WHERE created_at >= NOW() - INTERVAL '7 days'
WHERE created_at >= DATE_TRUNC('month', CURRENT_DATE)

MySQL

WHERE created_at >= DATE_SUB(NOW(), INTERVAL 7 DAY)
WHERE created_at >= DATE_FORMAT(NOW(), '%Y-%m-01')

SQLite

WHERE created_at >= DATE('now', '-7 days')
WHERE created_at >= DATE('now', 'start of month')

Examples

"Show me users who signed up this month"

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

"Find the top 5 products by sales"

SELECT p.name, SUM(oi.quantity) as total_sold
FROM products p
JOIN order_items oi ON p.id = oi.product_id
GROUP BY p.id, p.name
ORDER BY total_sold DESC
LIMIT 5;

"How many orders per customer?"

SELECT customer_id, COUNT(*) as order_count
FROM orders
GROUP BY customer_id
ORDER BY order_count DESC;

Safety Rules

• Always use LIMIT for exploratory queries (default: 100)
• Never generate DELETE, UPDATE, or DROP unless explicitly requested
• Warn if query might return large result sets
• Use table aliases for readability in JOINs