How to create a table using sql statement in mysql

To create a table in MySQL using SQL, you can use the CREATE TABLE statement. The syntax is: CREATE TABLE table_name (column_name data_type [NOT NULL] [DEFAULT default_value], ...). Among them, table_name is the name of the table, column_name is the name of the column, data_type is the data type of the column, NOT NULL specifies that the column cannot be empty, and DEFAULT default_value specifies the default value of the column. For example, to create a table named cu

How to create a table using SQL statements in MySQL

1. Basic syntax for creating a table

<code class="sql">CREATE TABLE table_name (
  column_name data_type [NOT NULL] [DEFAULT default_value],
  ...
);</code>

• table_name:The name of the table to be created.
• column_name: The name of the column.
• data_type: The data type of the column, such as INT, VARCHAR, DATE, etc.
• NOT NULL: The specified column cannot be NULL (null value).
• DEFAULT default_value: Specifies the default value of the column. If not specified, it defaults to NULL.

2. Example

Suppose you want to create a table named "customers" containing the following columns:

• id : INT, primary key, cannot be NULL
• name: VARCHAR(255), cannot be NULL
• email: VARCHAR(255), can be NULL, the default value is the empty string
• phone_number: VARCHAR(255), can be NULL, no default value

You can use the following SQL statement to create the table:

<code class="sql">CREATE TABLE customers (
  id INT NOT NULL AUTO_INCREMENT,
  name VARCHAR(255) NOT NULL,
  email VARCHAR(255) DEFAULT '',
  phone_number VARCHAR(255)
);</code>

3. Other notes Note

• Table names and column names are case-sensitive.
• The structure of each table must be unique, there cannot be two columns with the same column name.
• The primary key column must identify each record in the table and cannot contain NULL values.
• The default value can be a constant, expression or subquery.
• After you create a table, you can later use the ALTER TABLE statement to add, delete, or modify columns.

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