SELECT Queries

Query data with projections, aliases, and the DISTINCT keyword.

Basic SELECT

SELECT * FROM t;
SELECT id, name FROM t;

Column Aliases

SELECT id, val * 2.0 AS doubled FROM t;
SELECT id + 10 AS shifted FROM t;

DISTINCT

SELECT DISTINCT grp FROM data;
SELECT DISTINCT cat, region FROM sales;

Counting Rows

SELECT COUNT(*) FROM t;
SELECT COUNT(*) FROM t WHERE val >= 30.0;

Example from tests:

CREATE TABLE t (id INTEGER, val REAL, name VARCHAR);
INSERT INTO t VALUES (1, 10.0, 'alice'), (2, 20.0, 'bob'),
  (3, 30.0, 'carol'), (4, 40.0, 'dave'), (5, 50.0, 'eve');

-- Column projection with alias
SELECT id, val * 2.0 AS doubled FROM t ORDER BY id LIMIT 3;

Output: (1, 20.0), (2, 40.0), (3, 60.0)