What does column in mysql mean?

Columns (Column) in MySQL tables are vertically arranged data units that contain specific data types and attributes, such as names, data types, constraints, and default values. These properties define the characteristics of the column and the way it is used to store and organize data in the table.

Column (column) in MySQL

In the MySQL database, Column (column) is the data in the table A part of. It is a vertical arrangement of data in a table and contains specific types of data. Columns have the following important properties:

Name: A unique name that identifies the column.
Data type: Specify the data type stored in the column (for example, INT, VARCHAR, DATE).
Constraints: Define restrictions on the data in the column (for example, NOT NULL, UNIQUE).
Default value: When no value is specified, the value of the column is automatically populated when inserting a new record.

The role of columns

Columns are used to store and organize data in MySQL tables. They allow data to be classified and grouped into meaningful units. By combining multiple columns, you can create tables containing complex information.

Create columns

Use MySQL’s CREATE TABLE statement to create columns. Here's how to create a column with name "Name", data type "VARCHAR", length "50", and NULL is not allowed:

<code class="sql">CREATE TABLE people (
  Name VARCHAR(50) NOT NULL
);</code>

Modify Column

You can use the ALTER TABLE statement to modify the columns of an existing table. Here's how to change the data type of the "Name" column to "INT":

<code class="sql">ALTER TABLE people ALTER COLUMN Name INT;</code>

Deleting a column

You can delete a column using the ALTER TABLE statement . Here's how to delete the "Name" column:

<code class="sql">ALTER TABLE people DROP COLUMN Name;</code>

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