What is desc in mysql

DESC is the command in MySQL to view the table structure, using the syntax: DESC table_name. It outputs field information including name, type, null value allowed, index status, default value, and additional information. For example: DESC customers returns id (int, primary key, auto-increment), name (varchar(255), allows null values, has index), email (varchar(255), does not allow null values, unique index), phone (varchar() 255), allowing null values, with indexes), address (text, allowing null values, with indexes) and other field information.

What is DESC in MySQL?

DESC is a command in MySQL used to display the table structure. It lists all the fields in the table and their properties in human-readable form.

How to use DESC?

To use the DESC command, simply enter the following syntax at the MySQL prompt:

<code>DESC table_name;</code>

where table_name is the name of the table whose structure you want to query.

DESC Command Output

The DESC command will return the following information:

• Field: Field Name
• Type: Field data type
• Null: Indicates whether the field allows null values ​​(YES or NO)
• Key : Indicates whether the field is part of an index (primary key, unique index, etc.)
• Default: The default value of the field (if any)
• Extra: Additional information about the field (for example, auto-increment)

Example

For example, to view the customers table structure, you can use the following command:

<code>DESC customers;</code>

The output may look like this:

<code>Field           Type        Null    Key     Default  Extra
---------------- -------- -------- -------- -------- --------
id              int          NO      PRI     NULL     auto_increment
name            varchar(255) NO      MUL     NULL     
email           varchar(255) NO      UNI     NULL     
phone           varchar(255) YES     MUL     NULL     
address         text         YES     MUL     NULL     </code>

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