This page lists the most important SQL statements and contains links to their documentation pages. If you need a basic tutorial on how to use the MariaDB database server and how to execute simple commands, see [A MariaDB Primer](https://mariadb.com/docs/server/server-usage/basics/mariadb-usage-guide-1).
Also see [Common MariaDB Queries](https://mariadb.com/docs/server/mariadb-quickstart-guides/mariadb-advanced-sql-guide) for examples of commonly-used queries.
## Defining How Your Data Is Stored
* [CREATE DATABASE](https://mariadb.com/docs/server/reference/sql-statements/data-definition/create/create-database) is used to create a new, empty database.
* [DROP DATABASE](https://mariadb.com/docs/server/reference/sql-statements/data-definition/drop/drop-database) is used to completely destroy an existing database.
* [USE](https://mariadb.com/docs/server/reference/sql-statements/administrative-sql-statements/use-database) is used to select a default database.
* [CREATE TABLE](https://mariadb.com/docs/server/server-usage/tables/create-table) is used to create a new table, which is where your data is actually stored.
* [ALTER TABLE](https://mariadb.com/docs/server/reference/sql-statements/data-definition/alter/alter-table) is used to modify an existing table's definition.
* [DROP TABLE](https://mariadb.com/docs/server/server-usage/tables/drop-table) is used to completely destroy an existing table.
* [DESCRIBE](https://mariadb.com/docs/server/reference/sql-statements/administrative-sql-statements/describe) shows the structure of a table.
## Manipulating Your Data
* [SELECT](https://mariadb.com/docs/server/reference/sql-statements/data-manipulation/selecting-data/select) is used when you want to read (or select) your data.
* [INSERT](https://mariadb.com/docs/server/reference/sql-statements/data-manipulation/inserting-loading-data/insert) is used when you want to add (or insert) new data.
* [UPDATE](https://mariadb.com/docs/server/reference/sql-statements/data-manipulation/changing-deleting-data/update) is used when you want to change (or update) existing data.
* [DELETE](https://mariadb.com/docs/server/reference/sql-statements/data-manipulation/changing-deleting-data/delete) is used when you want to remove (or delete) existing data.
* [REPLACE](https://mariadb.com/docs/server/reference/sql-statements/data-manipulation/changing-deleting-data/replace) is used when you want to add or change (or replace) new or existing data.
* [TRUNCATE](https://mariadb.com/docs/server/reference/sql-statements/table-statements/truncate-table) is used when you want to empty (or delete) all data from the template.
## Transactions
* [START TRANSACTION](https://mariadb.com/docs/server/reference/sql-statements/transactions/start-transaction) is used to begin a transaction.
* [COMMIT](https://mariadb.com/docs/server/reference/sql-statements/transactions/commit) is used to apply changes and end transaction.
* [ROLLBACK](https://mariadb.com/docs/server/reference/sql-statements/transactions/rollback) is used to discard changes and end transaction.
### A Simple Example
```sql
CREATE DATABASE mydb;
USE mydb;
CREATE TABLE mytable ( id INT PRIMARY KEY, name VARCHAR(20) );
INSERT INTO mytable VALUES ( 1, 'Will' );
INSERT INTO mytable VALUES ( 2, 'Marry' );
INSERT INTO mytable VALUES ( 3, 'Dean' );
SELECT id, name FROM mytable WHERE id = 1;
UPDATE mytable SET name = 'Willy' WHERE id = 1;
SELECT id, name FROM mytable;
DELETE FROM mytable WHERE id = 1;
SELECT id, name FROM mytable;
DROP DATABASE mydb;
SELECT COUNT(1) FROM mytable; gives the NUMBER OF records IN the TABLE
```
*The first version of this article was copied, with permission, from* [*Basic\_SQL\_Statements*](https://hashmysql.org/wiki/Basic_SQL_Statements) *on 2012-10-05.*
*This page is licensed: CC BY-SA / Gnu FDL*
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