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PHP MySQL Create Database and Tables
PHP MySQL Create Database and TablesA database holds one or multiple tables. Create a DatabaseThe CREATE DATABASE statement is used to create a database in MySQL. Syntax
To learn more about SQL, please visit our SQL tutorial. To get PHP to execute the statement above we must use the mysql_query() function. This function is used to send a query or command to a MySQL connection. ExampleThe following example creates a database called "my_db":
Create a TableThe CREATE TABLE statement is used to create a table in MySQL. Syntax
To learn more about SQL, please visit our SQL tutorial. We must add the CREATE TABLE statement to the mysql_query() function to execute the command. ExampleThe following example creates a table named "Persons", with three columns. The column names will be "FirstName", "LastName" and "Age":
Important: A database must be selected before a table can be created. The database is selected with the mysql_select_db() function. Note: When you create a database field of type varchar, you must specify the maximum length of the field, e.g. varchar(15). The data type specifies what type of data the column can hold. For a complete
reference of all the data types available in MySQL, go to our complete
Data Types reference. Primary Keys and Auto Increment FieldsEach table should have a primary key field. A primary key is used to uniquely identify the rows in a table. Each primary key value must be unique within the table. Furthermore, the primary key field cannot be null because the database engine requires a value to locate the record. The following example sets the personID field as the primary key field. The primary key field is often an ID number, and is often used with the AUTO_INCREMENT setting. AUTO_INCREMENT automatically increases the value of the field by 1 each time a new record is added. To ensure that the primary key field cannot be null, we must add the NOT NULL setting to the field. Example
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