PHP date() format when inserting datetime in MySQL

MySQL retrieves and displays the DATETIME value in 'YYYY-MM-DD HH:MM:SS' format. Dates can only be stored in this type, but it can be used with many time format functions to change and display it.

#When writing a query in MySQL using PHP, its suitability is checked against MySQL itself. So use the default date and time format provided by MySQL, which is 'YYYY-MM-DD'

Example:

ATE: YYYY-MM-DD
Example: 2019-01-28

DATETIME: YYYY-MM-DD HH:MI:SS
Example: 2019-01-28 23:50:30

TIMESTAMP: YYYY-MM-DD HH:MI:SS
Example: 2019-01-28 23:50:30

YEAR: YYYY or YY

MySQL query for creating DataBase:

CREATE DATABASE Date_time_example;

Example 1: PHP program to create database and tables

<?php 
  
$servername = "localhost"; 
$username = "root"; 
$password = ""; 
$dbname = "test"; 
  
// 创建连接
$conn = mysqli_connect( $servername, $username, $password, $dbname ); 
  
// 检查连接 
if ( !$conn ) { 
    die("Connection failed: " . mysqli_connect_error()); 
} 
  
// 创建表的SQL查询 
$sql = "CREATE TABLE date_test ( 
    id INT AUTO_INCREMENT PRIMARY KEY, 
    created_at DATETIME 
)"; 
  
if (mysqli_query($conn, $sql)) { 
    echo "Table date_test created successfully"; 
} else { 
    echo "Error creating table: " . mysqli_error($conn); 
} 
  
// 关闭连接
mysqli_close($conn);

Output:

Table date_test created successfully

Example 2: PHP program to insert dates into a table.

<?php 
  
$servername = "localhost"; 
$username = "root"; 
$password = ""; 
$dbname = "test"; 
  
// 创建连接 
$conn = mysqli_connect( $servername, $username, $password, $dbname ); 
  
// 检查连接
if ( !$conn ) { 
    die("Connection failed: " . mysqli_connect_error()); 
} 
  
// 用于向表中插入数据的SQL查询 
$sql = "INSERT INTO date_test( created_at )  
        VALUES( &#39;2019-01-28 12:39:16&#39; );"; 
  
if (mysqli_query($conn, $sql)) { 
    echo "New record created successfully"; 
} else { 
    echo "Error: " . $sql . "<br>" . mysqli_error($conn); 
} 
  
// 关闭连接
mysqli_close($conn);

Output:

New record created successfully

Example 3: This example is used to display rows created on 2019-01-28. Use the following query to display the results. The created_at column contains not only the date but also the time. So it will show error message .

SELECT * FROM date_test WHERE DATE( created_at ) = '2019-01-28';

<?php 
  
$servername = "localhost"; 
$username = "root"; 
$password = ""; 
$dbname = "test"; 
  
//创建连接 
$conn = mysqli_connect( $servername, $username, $password, $dbname ); 
  
// 检查连接
if ( !$conn ) { 
    die("Connection failed: " . mysqli_connect_error()); 
} 
  
//SQL查询 
$sql = "SELECT * FROM date_test 
WHERE DATE(created_at) = &#39;2019-01-28&#39;"; 
  
$result = mysqli_query( $conn, $sql );  
  
if ($result) { 
    echo $result; //打印查询结果 
}  
else { 
    echo "Error: " . $sql . "<br>" . mysqli_error($conn); 
} 
  
// 关闭连接
mysqli_close($conn);

Output:

id  created_at
1   2019-01-28 12:39:16

To get the year, quarter, month, week, day, hour, minute and second from a DATETIME value, use the function shown in the following statement:
HOUR (@dt), MINUTE (@dt), SECOND (@dt) ), DAY (@dt), WEEK (@dt), MONTH (@dt), QUARTER (@dt), YEAR (@dt);

Recommended reference study:

《PHP Tutorial》http://www.php.cn/course/list/29.html

《mysql tutorial》http://www.php.cn/course/list/51.html

##

The above is the detailed content of PHP date() format when inserting datetime in MySQL. For more information, please follow other related articles on the PHP Chinese website!