Mysqli 简明教程
MySQLi - Create Table
首先，表格创建命令需要以下详细信息 -
To begin with, the table creation command requires the following details −
-
Name of the table
-
Name of the fields
-
Definitions for each field
Syntax
以下是一个用于创建 MySQL 表的通用 SQL 语法 −
Here is a generic SQL syntax to create a MySQL table −
CREATE TABLE table_name (column_name column_type);现在，我们在 TUTORIALS 数据库中创建以下表。
Now, we will create the following table in the TUTORIALS database.
create table tutorials_tbl(
tutorial_id INT NOT NULL AUTO_INCREMENT,
tutorial_title VARCHAR(100) NOT NULL,
tutorial_author VARCHAR(40) NOT NULL,
submission_date DATE,
PRIMARY KEY ( tutorial_id )
);此处，需要对几个项目进行说明 -
Here, a few items need explanation −
-
Field Attribute NOT NULL is being used because we do not want this field to be NULL. So, if a user will try to create a record with a NULL value, then MySQL will raise an error.
-
Field Attribute AUTO_INCREMENT tells MySQL to go ahead and add the next available number to the id field.
-
Keyword PRIMARY KEY is used to define a column as a primary key. You can use multiple columns separated by a comma to define a primary key.
Creating Tables from Command Prompt
很容易从 mysql> 提示符创建 MySQL 表。您将使用 SQL 命令 CREATE TABLE 来创建表。
It is easy to create a MySQL table from the mysql> prompt. You will use the SQL command CREATE TABLE to create a table.
Example
这是一个示例，它将创建 tutorials_tbl −
Here is an example, which will create tutorials_tbl −
root@host# mysql -u root -p
Enter password:*******
mysql> use TUTORIALS;
Database changed
mysql> CREATE TABLE tutorials_tbl(
→ tutorial_id INT NOT NULL AUTO_INCREMENT,
→ tutorial_title VARCHAR(100) NOT NULL,
→ tutorial_author VARCHAR(40) NOT NULL,
→ submission_date DATE,
→ PRIMARY KEY ( tutorial_id )
→ );
Query OK, 0 rows affected (0.16 sec)
mysql>NOTE - MySQL 在 SQL 命令末尾输入分号 (;) 之前不会终止命令。
NOTE − MySQL does not terminate a command until you give a semicolon (;) at the end of SQL command.
Creating Tables Using PHP Script
PHP 使用 mysqli query() 或 mysql_query() 函数来创建 MySQL 表。这个函数接收两个参数，并在成功时返回 TRUE，并在失败时返回 FALSE。
PHP uses mysqli query() or mysql_query() function to create a MySQL table. This function takes two parameters and returns TRUE on success or FALSE on failure.
Syntax
$mysqli→query($sql,$resultmode)Sr.No. |
Parameter & Description |
1 |
$sql Required - SQL query to create a MySQL table. |
2 |
$resultmode Optional - Either the constant MYSQLI_USE_RESULT or MYSQLI_STORE_RESULT depending on the desired behavior. By default, MYSQLI_STORE_RESULT is used. |
Example
尝试以下示例以创建一个表 −
Try the following example to create a table −
将以下示例复制粘贴为 mysql_example.php：
Copy and paste the following example as mysql_example.php −
<html>
<head>
<title>Creating MySQL Table</title>
</head>
<body>
<?php
$dbhost = 'localhost';
$dbuser = 'root';
$dbpass = 'root@123';
$dbname = 'TUTORIALS';
$mysqli = new mysqli($dbhost, $dbuser, $dbpass, $dbname);
if($mysqli→connect_errno ) {
printf("Connect failed: %s<br />", $mysqli→connect_error);
exit();
}
printf('Connected successfully.<br />');
$sql = "CREATE TABLE tutorials_tbl( ".
"tutorial_id INT NOT NULL AUTO_INCREMENT, ".
"tutorial_title VARCHAR(100) NOT NULL, ".
"tutorial_author VARCHAR(40) NOT NULL, ".
"submission_date DATE, ".
"PRIMARY KEY ( tutorial_id )); ";
if ($mysqli→query($sql)) {
printf("Table tutorials_tbl created successfully.<br />");
}
if ($mysqli→errno) {
printf("Could not create table: %s<br />", $mysqli→error);
}
$mysqli→close();
?>
</body>
</html>