SQL SELECT Statement

Chapter 3 of 40 · Estimated read time: 7 min

The SELECT statement is the most used SQL command. It retrieves data from one or more tables. The result is returned as a temporary result set called the result-set.

Syntax

Example 1 — Select Specific Columns

Select only the product name and price from the products table:

SELECT product_name, price
FROM products;

Example 2 — Select All Columns with *

Use * (asterisk) to select every column in the table:

SELECT *
FROM products;

Example 3 — Expressions and Calculations

You can calculate new values directly in SELECT:

-- Price including 18% GST
SELECT
  product_name,
  price,
  price * 1.18        AS price_with_gst,
  stock * price       AS inventory_value
FROM products;

Example 4 — Select a Literal Value

You can select constant values — useful for adding a fixed label column:

SELECT
  product_name,
  price,
  'INR'          AS currency,
  'In Stock'     AS status
FROM products
WHERE stock > 0;

Example 5 — Combine Strings (Concatenation)

-- PostgreSQL / BigQuery: use ||
SELECT
  customer_name || ' (' || city || ')' AS customer_with_city
FROM customers;

-- MySQL: use CONCAT()
SELECT
  CONCAT(customer_name, ' (', city, ')') AS customer_with_city
FROM customers;

-- 1.
SELECT customer_name, city FROM customers;

-- 2.
SELECT product_name, price, price * 0.90 AS discounted_price FROM products;

-- 3.
SELECT order_id, customer_id, total_amount / 1000.0 AS amount_k FROM orders;