Welcome to my Blog! This is my first article. The following are my study notes for learning Servlet.

Reasonable use of SQL statements

String sql = "insert into T_BOOK(BID,BNAME,BAUTHER,BTYPE,BPRICE,BAMOUNT,BPUBDATE)";
sql=sql+" values('"+BID+"','"+BNAME+"','"+BAUTHER+"','"+BTYPE+"','"+BPRICE+"',"+BAMOUNT+",'"+BPUBDATE+"')";

String sql = "update T_BOOK set BAMOUNT = "+BAMOUNT+" where BID = '"+BID+"'";

String sql = "select * from T_BOOK where BNAME like '%"+input+"%'";

String sql = "select * from T_BOOK where BPRICE between "+Low+" and "+High;

Proficiency in the SQL language is a prerequisite for implementing various operations through the servlet link to the database.

Mastering the most basic insert, update and conditional search statements can achieve most database operations.

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Connect to the database via JDBC

Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver").newInstance();
			String url="jdbc:sqlserver://localhost:1433;databaseName=?";
			String user="user";
			String password="password";
			conn=DriverManager.getConnection(url, user, password);

The project adopting MVC mode is to use JDBC technology to connect to the database.

Please add sqljdbc.jar in the lib folder of WEB-INF to ensure that JDBC can be successfully called.

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Use of Servlet annotations

@WebServlet("/Classname")

Using Servlet annotations can eliminate extra comments in web.xml, making the program more concise and portable.

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Thank you for reading, I hope these tips can help you learn Servlet better.