JSP Database Connection JSP Standard Tag Library (JSTL)

<sql:dateParam> tag

The <sql:dateParam> tag is used in conjunction with the <sql:query> tag and <sql:update> tag to provide placeholders for dates and times. If it is a null value, the placeholder is set to SQL NULL.

Syntax format

<sql:dateParam value="<string>" type="<string>"/>

Attribute

The <sql:dateParam> tag has the following attributes:

Attribute	Description	Is it necessary	Default value
value	Date parameter to be set (java.util.Date)	No	Body
type	DATE (only date), TIME (only time), TIMESTAMP (date and time)	No	TIMESTAMP

Example demonstration

Firstly, you need to create an Employees table in the TEST database and then add several records to the table. The specific operation steps are as follows:

　　 Step1:

Open CMD, change the directory to the installation directory:

C:\>
C:\>cd Program Files\MySQL\bin
C:\Program Files\MySQL\bin>

　　 Step2:

C:\Program Files\MySQL\bin>mysql　-u root　-p
Enter password:　********
mysql>

　　 Step3:

Establish the Employees table in the TEST database:

mysql> use TEST;
mysql> create table Students
　　　　(
　　　　　id int not null,
　　　　　first varchar (255),
　　　　　last varchar (255),
　　　　　dob date
　　　　);
Query OK, 0 rows affected (0.08　sec)
mysql>

Create data records:}}

Finally, create several records in the Students table:

mysql> INSERT INTO Students　
　　　　　　　　　　VALUES (100, 'Zara', 'Ali', '2002/05/16);
Query OK,　1　row affected (0.05　sec)
　
mysql> INSERT INTO Students　
　　　　　　　　　　VALUES (101, 'Mahnaz', 'Fatma', '1978/11/28);
Query OK,　1　row affected (0.00 sec)
　
mysql> INSERT INTO Students　
　　　　　　　　　　VALUES (102, 'Zaid', 'Khan', '1980/10/10);
Query OK,　1　row affected (0.00 sec)
　
mysql> INSERT INTO Students　
　　　　　　　　　　VALUES (103, 'Sumit', 'Mittal', '1971/05/08);
Query OK,　1　row affected (0.00 sec)
　
mysql>

Now write a JSP file to use the <sql:update> tag, <sql:param> tag, and <sql:dateParam> tag to execute the SQL UPDATE statement and update Zara's birthday:

<%@ page language="java" contentType="text/html; charset=UTF-8"
　　　　pageEncoding="UTF-8"%>
<%@ page import="java.io.*,java.util.*,java.sql.*"%>
<%@ page import="javax.servlet.http.*,javax.servlet.*"  %>
<%@ page import="java.util.Date,java.text.*"  %>
<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%>
<%@ taglib uri="http://java.sun.com/jsp/jstl/sql" prefix="sql"%>
　
<html>
<head>
<title>JSTL sql:dataParam Tag</title>
</head>
<body>
　
<sql:setDataSource var="snapshot" driver="com.mysql.jdbc.Driver"
　　　　　url="jdbc:mysql://localhost/TEST"
　　　　　user="root"  password="pass123"/>
<%
Date DoB = new Date("2001/12/16");
int studentId =　100;
%>
　
<sql:update dataSource="${snapshot}" var="count">
　　　UPDATE Students SET dob = ? WHERE Id = ?
　　　<sql:dateParam value="<%=DoB%>" type="DATE"　/>
　　　<sql:param value="<%=studentId%>"　/>
</sql:update>
　
<sql:query dataSource="${snapshot}" var="result">
　　　SELECT　*　from Students;
</sql:query>
　
<table border="1" width="100%">
<tr>
　　　<th>Emp ID</th>
　　　<th>First Name</th>
　　　<th>Last Name</th>
　　　<th>DoB</th>
</tr>
<c:forEach var="row" items="${result.rows}">
<tr>
　　　<td><c:out value="${row.id}"/></td>
　　　<td><c:out value="${row.first}"/></td>
　　　<td><c:out value="${row.last}"/></td>
　　　<td><c:out value="${row.dob}"/></td>
</tr>
</c:forEach>
</table>
　
</body>
</html>

The running result is as follows:

JSP Standard Tag Library