What are the main MySQL commands?

To make the most of the features of this database, it is important to know the main MySQL commands and operations. In this article, we will explore the main MySQL commands, from managing databases and tables, to creating and managing users and permissions.

So, by the end of this article, we will learn MySQL using the basic commands and will have a solid understanding of the way they can be used to manage and optimize your database.

Main commands for managing the MySQL database

Database management is a fundamental aspect of MySQL as it allows the user to create, manage and modify the data stored in its database.

Create a database

To create a new database, the user can use the CREATE DATABASE command. Thus, this command allows you to set database configuration options such as the database name, header file location, and block page size.

Example:

CREATE DATABASE database_name;

In the example, it creates a new database called “database_name”. Thus, the “CREATE DATABASE” command is used to create a new database. So this command is used to create a new database.

Delete a database

To delete a database, the user can use the DROP DATABASE command. This command allows you to delete a specific database as well as all database objects associated with it.

 Example:

DROP DATABASE database_name;

This code deletes the database “database_name”. Thus, the “DROP DATABASE” command is used to delete a database. This way, we use the command to delete a database.

Rename a database

To rename a database, the user can use the RENAME DATABASE command. Thus, this command allows you to change the name of an existing database to another name.

Change a database configuration

To change the configuration of a database, the user can use the ALTER DATABASE command. This allows you to change database configuration options such as the database name, header file location, and block page size.

Example:

ALTER DATABASE database_name
ADD FILENAME='file_location'
WITH FILENAME = 'file_location';

This code changes the database “name_of_the_bank_of_data” by adding a new header file located in “file_location”. Thus, the “ ” command ADD FILENAME adds a new file, and the “WITH FILENAME” parameter specifies the location of the added file.

Create a table

To create a new table, the user can use the CREATE TABLE command. Thus, this command allows you to define the table name, the table columns, and the data types for each column.

Example:

CREATE TABLE nome_da_tabela (
    column1 datatype,
    column2 datatype,
    column3 datatype
);

This code creates a new table called “table_name” with three columns: “column1”, “column2” and “column3”. Each column has a data type specified in parentheses, such as “datatype”. The “CREATE TABLE” command is used to create a new table. Parentheses are used to delimit the columns and data types in each column.

Delete a table

To delete a table, the user can use the DROP TABLE command. Thus, this command allows you to delete a specific table from the database.

Example:

DROP TABLE table_name;

This code deletes the table “table_name” from the database. The “DROP TABLE” command is used to delete a specific table from the database. So this command is used to delete a table.

Rename a table

To rename a table, the user can use the RENAME TABLE command. This command allows you to change the name of an existing table to another name.

Example:

RENAME TABLE table_name TO new_table_name;

This code renames the table “table_name” to “new_table_name”. Therefore, the “RENAME TABLE” command is used to change the name of an existing table. Parentheses are used to specify the new table name. This command is used to rename a table.

Change the structure of a table

To change the structure of a table, the user can use the ALTER TABLE command. In this sense, the command allows you to add, remove or modify columns from an existing table.

Example:

ALTER TABLE table_name
ADD column_new datatype;

This code adds a new column called “new_column” to the “table_name” table with the data type “datatype”. Thus, we use the “ALTER TABLE” command to modify the structure of an existing table. Parentheses are used to specify the table name and the new data type of the added column.

In summary, MySQL offers a wide range of core commands to manage your databases and tables. With these commands, the user can create, delete, rename, and modify database objects, as well as change the configuration of a database. Thus, with these tools, the user can manage their information efficiently and effectively.

Table management in MySQL

Table management is one of the most important features of MySQL. Tables store data in a database and allow you to query and manipulate data according to your needs.

Insert data into a table:

To insert data into a table, you can use the INSERT command. The INSERT command allows you to add one or more rows to a table. Thus, this way, the command would look like this:

INSERT INTO table_name (column_name1, column_name2, column_name3) VALUES (value1, value2, value3);

The statement “INSERT INTO table_name” indicates that the record will be inserted into the table called “table_name”. Thus, the instruction specifies the names of the table columns, “column_name1”, “column_name2” and “column_name3”, which will be filled with the values ​​“value1”, “value2” and “value3”, respectively.

Update data in a table:

To update data in a table, you can use the UPDATE command. The UPDATE command allows you to change the value of one or more columns in one or more rows in a table. Thus, the command would look like this:

UPDATE table_name SET column_name = value WHERE condition;

Delete data from a table

To delete data from a table, you can use the DELETE command. The DELETE command allows you to delete one or more rows from a table. Thus, the command would look like this:

DELETE FROM table_name WHERE condition;

Select data from a table

To select data from a table, you can use the SELECT command. The SELECT command allows you to select one or more columns from a table. Thus, the command would look like this:

SELECT column_name1, column_name2, column_name3 FROM table_name;

Sort data in a table:

To order data in a table, you can use the ORDER BY command. The ORDER BY command allows you to organize data in a table according to one or more columns. Thus, the command would look like this:

SELECT column_name1, column_name2, column_name3 FROM table_name ORDER BY column_name1 ASC;

Filter data in a table

To filter data in a table, you can use the WHERE command. The WHERE command allows you to select only those rows that match a specific condition. Thus, the command would look like this:

SELECT column_name1, column_name2, column_name3 FROM table_name WHERE column_name1 = 'value';

So, these are the main commands to manage tables in MySQL. With these commands, you can create, change, delete and query data in your database according to your needs.

A very important practice is to use indexes appropriately to optimize queries and perform regular backups of the database – Comments Gustavo Carvalho

Commands for users and permissions in MySQL

User and permissions management is an important part of MySQL, as it allows you to control who has access to your tables and data. Thus, this way, we use the main MySQL commands to create, delete, edit and assign permissions to specific users to control access to your database.

Create a user:

To create a user in MySQL, you can use the GRANT command. The GRANT command allows you to assign privileges to a specific user. Thus, the command would look like this:

GRANT USAGE ON *.* TO 'user_name'@'localhost' IDENTIFIED BY 'password';

Delete a user:

To delete a MySQL user, you can use the REVOKE command. The REVOKE command allows you to revoke privileges from a specific user. Thus, the command would look like this:

REVOKE USAGE ON *.* FROM 'user_name'@'localhost';

Where “user_name” is the name of the user you want to delete.

Change a user’s permissions:

To change a user’s permissions in MySQL, you can use the GRANT command. In this sense, the GRANT command allows you to assign privileges to a specific user. Thus, the command would look like this:

GRANT ALL PRIVILEGES ON *.* TO 'user_name'@'localhost' IDENTIFIED BY 'password';

Where “username” is the name of the user you want to change permissions and “password” is the password you want to associate with the user.

Assign permissions to a user:

To assign permissions to a user in MySQL, you can use the GRANT command. The GRANT command allows you to assign privileges to a specific user. Thus, the command would look like this:

GRANT SELECT, INSERT, UPDATE, DELETE, CREATE, DROP, INDEX ON *.* TO 'username'@'localhost' IDENTIFIED BY 'password';

Thus, where “username” is the name of the user you want to assign permissions to and “password” is the password you want to associate with the user.

Remove permissions from a user:

To remove permissions from a user in MySQL, you can use the REVOKE command. Thus, the REVOKE command allows you to revoke privileges from a specific user. The command would look like this:

REVOKE SELECT, INSERT, UPDATE, DELETE, CREATE, DROP, INDEX ON *.* FROM 'user_name'@'localhost';

Where “username” is the name of the user you want to remove permissions from.

These are the main commands to manage users and permissions in MySQL. So with these commands you can create users, delete users, change permissions, assign permissions and remove permissions from specific users. It’s important to remember that security is a critical part of any data management system, so it’s important to maintain control over access to your tables and data.