This is a small sql cheat sheet i keep. It contains super basic operations (create, select, delete). I am using Mysql for demo here but there would be some difference with sqlite or postgresql.

Start Mysql Link to heading

to connect to server for first time, you need to connect as root

sudo mysql

Create user and add privileges Link to heading

CREATE USER 'user'@'localhost' IDENTIFIED BY 'password'

mysql> GRANT ALL PRIVILEGES ON *.* TO 'user'@'localhost';
Query OK, 0 rows affected (0.02 sec)

mysql> FLUSH PRIVILEGES;
Query OK, 0 rows affected (0.00 sec)

Create, show delete databases Link to heading

mysql> CREATE DATABASE acme;
Query OK, 1 row affected (0.01 sec)

mysql> SHOW DATABASES;
+--------------------+
| Database           |
+--------------------+
| acme               |
| information_schema |
| mysql              |
| performance_schema |
+--------------------+
7 rows in set (0.01 sec)

mysql> DROP DATABASE acme;

Connect to database Link to heading

mysql> USE acme;

Tables Link to heading

list tables

mysql> SHOW TABLES;

Create table

mysql> CREATE TABLE users( id INT AUTO_INCREMENT, first_name VARCHAR(100), register_date DATETIME, PRIMARY KEY(id) );
Query OK, 0 rows affected (0.06 sec)

Delete table

mysql> DROP TABLE users;
Query OK, 0 rows affected (0.04 sec)

INSERT Link to heading

mysql> INSERT INTO users (first_name, register_date)
    -> values('a', now())
    -> ;
Query OK, 1 row affected (0.01 sec)

mysql> SELECT * FROM users;
+----+------------+---------------------+
| id | first_name | register_date       |
+----+------------+---------------------+
|  1 | a          | 2020-08-09 22:43:52 |
+----+------------+---------------------+
1 row in set (0.00 sec)

SELECT Link to heading

Select all columns

mysql> SELECT * FROM users;
+----+------------+---------------------+
| id | first_name | register_date       |
+----+------------+---------------------+
|  1 | a          | 2020-08-09 22:43:52 |
+----+------------+---------------------+
1 row in set (0.00 sec)

Select one column

mysql> SELECT first_name FROM users;
+------------+
| first_name |
+------------+
| a          |
+------------+
1 rows in set (0.00 sec)

const

mysql> SELECT first_name FROM users WHERE first_name='a';
+------------+
| first_name |
+------------+
| a          |
+------------+
1 row in set (0.00 sec)

DELETE Link to heading

mysql> DELETE FROM users WHERE id=1;
Query OK, 1 row affected (0.00 sec)

mysql> SELECT first_name FROM users;
+------------+
| first_name |
+------------+
| b          |
+------------+
1 row in set (0.00 sec)

Update Link to heading

mysql> UPDATE users SET first_name='aa' WHERE id=2;
Query OK, 1 row affected (0.01 sec)
Rows matched: 1  Changed: 1  Warnings: 0

mysql> SELECT first_name FROM users;
+------------+
| first_name |
+------------+
| aa         |
+------------+
1 row in set (0.01 sec)

ALTER table Link to heading

mysql> SELECT first_name FROM users;
+------------+
| first_name |
+------------+
| aa         |
+------------+
1 row in set (0.00 sec)

mysql> SELECT * FROM users;
+----+------------+---------------------+------+
| id | first_name | register_date       | age  |
+----+------------+---------------------+------+
|  2 | aa         | 2020-08-09 22:46:42 | NULL |
+----+------------+---------------------+------+
1 row in set (0.00 sec)

mysql> UPDATE users SET age=4 WHERE id=2;
Query OK, 1 row affected (0.02 sec)
Rows matched: 1  Changed: 1  Warnings: 0

Order Link to heading

mysql> SELECT * FROM users ORDER BY age;
+----+------------+---------------------+------+
| id | first_name | register_date       | age  |
+----+------------+---------------------+------+
|  3 | u2         | 2020-08-09 23:00:43 | NULL |
|  2 | aa         | 2020-08-09 22:46:42 |    4 |
+----+------------+---------------------+------+

Conditions - BETWEEN (Filter) Link to heading

mysql> SELECT * FROM users WHERE age BETWEEN 1 AND 3;
+----+------------+---------------------+------+
| id | first_name | register_date       | age  |
+----+------------+---------------------+------+
|  3 | u2         | 2020-08-09 23:00:43 |    2 |
+----+------------+---------------------+------+
1 row in set (0.00 sec)

Conditions - LIKE (Search) Link to heading

mysql> SELECT * FROM users WHERE first_name LIKE 'u%';
+----+------------+---------------------+------+
| id | first_name | register_date       | age  |
+----+------------+---------------------+------+
|  3 | u2         | 2020-08-09 23:00:43 |    2 |
+----+------------+---------------------+------+

Conditions - IN Link to heading

mysql> SELECT * FROM users WHERE first_name IN('u2');
+----+------------+---------------------+------+
| id | first_name | register_date       | age  |
+----+------------+---------------------+------+
|  3 | u2         | 2020-08-09 23:00:43 |    2 |
+----+------------+---------------------+------+
1 row in set (0.00 sec)