You can get data out of tables using the SELECT
command.
Get all rows and columns:
SELECT * FROM people;
age | name
-----+--------
37 | Flavio
8 | Roger
Get only the name
column:
SELECT name FROM people;
name
--------
Flavio
Roger
Count the items in the table:
SELECT COUNT(*) from people;
count
-------
2
You can filter rows in a table adding the WHERE
clause:
SELECT age FROM people WHERE name='Flavio';
age
-----
37
The results of a query can be ordered by column value, ascending (the default) or descending, using ORDER BY:
SELECT * FROM people ORDER BY name;
SELECT * FROM people ORDER BY name DESC;
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