Developer & tech

SQL Query Generator

Fill in what you want back and read the query it produces. The explanation matters more than the SQL — a query you cannot read you cannot trust.

DatabaseTableColumnsComma separated. Leave blank for every column.Filter (WHERE)Join tableLeave blank for a single-table query.AggregateSort bySort highest / newest firstRemove duplicate rows (DISTINCT)Row limitSet to 0 for no limit.

Your query

SELECT id, customer_id, amount, created_at
FROM orders
WHERE status = 'paid'
ORDER BY created_at DESC
LIMIT 50;

What it does

1. Selects 4 named columns from the table.
2. Filters rows before grouping.
3. Sorts highest first.
4. Returns at most 50 rows.

Before you run it

Postgres folds unquoted identifiers to lowercase; anything created with mixed case must stay double-quoted.

Habits that keep queries safe

Run every new query as a SELECT first, even when the goal is an UPDATE or DELETE. Confirm the row count is what you expect, then swap the verb. Wrapping the change in a transaction you can roll back costs nothing and saves the occasional catastrophe.

Never build a WHERE clause by joining strings together with user input. Bound parameters are supported by every driver and remove an entire class of vulnerability. This page is a scaffold for a query you will parameterise, not a runtime query builder.

Check the plan before shipping. EXPLAIN on a table with production-scale data tells you whether your filter uses an index; a query that returns instantly on a thousand dev rows can time out on a million real ones.