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MySQL ALTER DATABASE: Modify Database

The ALTER DATABASE statement in MySQL is used to modify the options of an existing database. For instance, you can use it to change the character set and collation of a database.

Prerequisites:

A MySQL server up and running.
Access to a MySQL user account with privileges to create, modify, and alter databases.

Tutorial:

Connect to the MySQL server:

To start the mysql command-line client, open your terminal or command prompt, and enter:

mysql -u [username] -p

Replace [username] with your MySQL username and enter your password when prompted.

Using the ALTER DATABASE statement:

The basic syntax for using the ALTER DATABASE statement is as follows:

ALTER DATABASE database_name CHARACTER SET = charset_name COLLATE = collation_name;

Replace database_name with the name of your database, charset_name with the name of your character set, and collation_name with the name of your collation.

For example, to change the character set and collation of a database named mydb to utf8mb4 and utf8mb4_unicode_ci, you would use:

ALTER DATABASE mydb CHARACTER SET = utf8mb4 COLLATE = utf8mb4_unicode_ci;

This will change the default character set and collation of the mydb database to utf8mb4 and utf8mb4_unicode_ci, respectively. Note that this doesn't change the character set and collation of the tables and columns inside the database; you would need to use the ALTER TABLE statement to do that.

Exit the MySQL command-line client:

EXIT;

By using the ALTER DATABASE statement in MySQL, you can easily modify the options of an existing database. This can be useful for changing the character set and collation of a database to support different languages and sort orders, among other things.

How to Modify a MySQL Database with ALTER DATABASE:
- The ALTER DATABASE statement is used to modify various aspects of a MySQL database.
```
ALTER DATABASE database_name
[OPTIONS];
```
Changing Database Options with ALTER DATABASE in MySQL:
- Adjusting database options, such as enabling or disabling features.
```
ALTER DATABASE mydb
CHARACTER SET utf8mb4
COLLATE utf8mb4_unicode_ci;
```
Adding Character Set and Collation to a MySQL Database:
- Specifying the character set and collation during database creation or modification.
```
ALTER DATABASE mydb
CHARACTER SET utf8
COLLATE utf8_general_ci;
```
Modifying Database Attributes with ALTER DATABASE in MySQL:
- Changing various database attributes using ALTER DATABASE.
```
ALTER DATABASE mydb
DEFAULT CHARACTER SET utf8mb4
DEFAULT COLLATE utf8mb4_unicode_ci;
```
MySQL ALTER DATABASE Example:
- A general example of using ALTER DATABASE.
```
ALTER DATABASE mydb
CHARACTER SET utf8
COLLATE utf8_general_ci;
```
Renaming a MySQL Database with ALTER DATABASE:
- Renaming a MySQL database.
```
ALTER DATABASE old_db_name
RENAME TO new_db_name;
```
Altering Default Storage Engine for a MySQL Database:
- Changing the default storage engine for tables in a database.
```
ALTER DATABASE mydb
DEFAULT STORAGE ENGINE = InnoDB;
```
Setting Default Privileges with ALTER DATABASE in MySQL:
- Specifying default privileges for newly created objects in the database.
```
ALTER DATABASE mydb
DEFAULT PRIVILEGES ON *.* TO 'new_user'@'localhost';
```
Adjusting MySQL Database Character Set and Collation:
- Fine-tuning character set and collation settings.
```
ALTER DATABASE mydb
CHARACTER SET utf8mb4
COLLATE utf8mb4_unicode_ci;
```
Adding or Removing Database Options with ALTER DATABASE:
- Including or excluding specific options during the alteration.
```
ALTER DATABASE mydb
COMMENT = 'New comment';
```
MySQL ALTER DATABASE and Time Zone Considerations:
- Considering time zone settings during database modification.
```
ALTER DATABASE mydb
TIME_ZONE = '+00:00';
```