What does char mean in mysql

In MySQL, the CHAR type is used to store fixed-length text data, such as ID numbers. Features include: fixed length, space filling, space efficiency, and superior performance. To use the CHAR type, specify the column length using the CHAR(length) syntax when creating the table, for example: CREATE TABLE customers (last_name CHAR(30), first_name CHAR(15)).

CHAR type in MySQL

In the MySQL database, CHAR is a fixed-length string data type. It is used to store text data that is always the same length, such as last name, zip code, or ID number.

Features:

• Fixed length: CHAR columns always store data of the specified length, regardless of the actual text data length.
• Padding: If the actual text data length is less than the specified length, the remaining space of the CHAR column will be filled with spaces.
• Space efficiency: For text data with small length changes, the CHAR type can utilize storage space more efficiently.
• Performance: CHAR columns generally have better performance than VARCHAR columns because the database does not need to dynamically adjust the length of the column to accommodate data of different lengths.

How to use the CHAR type:

When creating a table, use the following syntax to define a CHAR column:

<code>CREATE TABLE table_name (
    column_name CHAR(length)
);</code>

Where, length Specifies the length of the CHAR column in characters.

Example:

<code>CREATE TABLE customers (
    last_name CHAR(30),
    first_name CHAR(15)
);</code>

This statement will create a customers table containing two CHAR columns: last_name( 30 characters in length) and first_name (15 characters in length).

Some points to note:

• The actual length of text data that can be stored in a CHAR column cannot exceed the specified length.
• If you try to insert text data that exceeds the specified length into a CHAR column, the text data will be truncated.
• The CHAR type is not suitable for storing variable-length text data, such as articles or comments.

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