MySQL Zerofill - SQL

MySQL Zerofill is a feature in the SQL programming language that allows numeric data to be automatically padded with zeros to a specific length. This can be useful in cases where sorting or displaying data requires the values to be formatted in a specific way.

Syntax

The Zerofill feature can be added to any numeric data type in MySQL using the following syntax:

column_name data_type(length) ZEROFILL

For example, to create a table with an integer column that is Zerofill enabled:

CREATE TABLE users (
    id INT(6) ZEROFILL,
    name VARCHAR(30)
);

Usage

Once a column has been created with Zerofill enabled, any values inserted into that column will be automatically padded with zeros to the specified length.

INSERT INTO users (id, name) VALUES (1, 'John');

The value 1 will be automatically padded with zeros to a length of 6 when it is inserted into the id column. This means that the value stored in the column will be '000001', even though only '1' was inserted.

Sorting

Zerofill can also be useful when sorting data. By padding values with zeros to a specific length, sorting can be performed correctly, even if the values have different lengths.

For example, consider the following data set:

1
10
2
20

If this data set was sorted without Zerofill, it would be sorted as follows:

1
10
2
20

However, if Zerofill is used to pad the values to a length of 2, the data set can be sorted correctly:

01
02
10
20

Conclusion

MySQL Zerofill is a useful feature in the SQL programming language that allows numeric data to be padded with zeros to a specific length. This can be useful in cases where sorting or displaying data requires the values to be formatted in a specific way.