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This article will explain in detail how mysql creates tables for everyone, Xiaobian thinks it is quite practical, so share it with you for a reference, I hope you can gain something after reading this article.

mysql creates tables by first specifying the names of the tables to be created after the CREATE TABLE clause; then specifying the list of tables in the column_list section; and finally specifying the storage engine for the tables in the engine clause.

MySQL creates tables:

The syntax of the CREATE TABLE statement is explained in simple form below:

CREATE TABLE [IF NOT EXISTS] table_name( column_list) engine=table_type;

First, specify the name of the table to be created after the CREATE TABLE clause. Table names must be unique in the database. IF NOT EXISTS is an optional part of the statement that allows you to check whether the table you are creating already exists in the database. If this is the case, MySQL ignores the entire statement and does not create any new tables. It is strongly recommended to use IF NOT EXISTS in each CREATE TABLE statement to prevent errors from creating new tables that already exist.

Second, specify the list of tables in the column_list section. Columns of fields are separated by commas (,). We'll show you how to define columns in more detail in the next section.

Third, you need to specify a storage engine for the tables in the engine clause. Any storage engine can be used, such as: InnoDB, MyISAM, HEAP, EXAMPLE, CSV, ARCHIVE, MERGE, FEDERATED or NDBCLUSTER. MySQL defaults to InnoDB if the storage engine is not explicitly declared.

Note: InnoDB has been the default storage engine since MySQL 5.5. The InnoDB table type brings many of the benefits of a relational database management system such as ACID transactions, referential integrity, and crash recovery. In previous versions, MySQL used MyISAM as the default storage engine.

To define columns for a table in a CREATE TABLE statement, use the following syntax:

column_name data_type[size] [NOT NULL|NULL] [DEFAULT value] [AUTO_INCREMENT]

The most important components of the above grammar are:

column_name Specifies the name of the column. Each column has a specific data type and size, for example VARCHAR(255).

NOT NULL or NULL indicates whether the column accepts NULL values.

DEFAULT The default value for the specified column.

AUTO_INCREMENT indicates that the value of the column is automatically incremented each time a new row is inserted into the table. Each table has one and only one AUTO_INCREMENT column.

For example:

CREATE TABLE IF NOT EXISTS tasks ( task_id INT(11) NOT NULL AUTO_INCREMENT, subject VARCHAR(45) DEFAULT NULL, start_date DATE DEFAULT NULL, end_date DATE DEFAULT NULL, description VARCHAR(200) DEFAULT NULL, PRIMARY KEY (task_id)) ENGINE=InnoDB; About "mysql how to create a table" this article is shared here, I hope the above content can be of some help to everyone, so that you can learn more knowledge, if you think the article is good, please share it for more people to see.

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