GCSf4PLM

1package Reviseknowledge;
2import java.sql.Connection;
3import java.sql.DriverManager;
4import java.sql.PreparedStatement;
5import java.sql.ResultSet;
6import java.util.ArrayList;
7
8public class Learn {
9
10	public static void main(String[] args) throws Exception {
11	
12	
13		
14	}
15
16	
17	static String url = "jdbc:mysql://localhost:3306/guest";
18	static String username = "root";
19	static String password = "guest123";
20	
21	
22	
23
24	public static void customSelection () throws Exception {
25		
26		try {
27			
28			Connection conn = DriverManager.getConnection(url,username,password);
29			
30			PreparedStatement custom = conn.prepareStatement ( "SELECT * from stebuklas where numbers < 10 ");
31			
32			ResultSet res = custom.executeQuery ();
33			
34		
35			
36			while ( res.next() ) {
37				
38				System.out.println ( res.getString ("first") + "\t" + res.getString ("last") + res.getInt("numbers") );
39			
40			}
41			
42			
43			
44			
45		}
46		catch(Exception e){ System.out.println(e); } 
47	}
48	
49	
50public static void update () throws Exception {  // UPDATE UPDATE, remove old ones and replace them.
51		
52		try{
53			
54			Connection conn = DriverManager.getConnection(url,username,password);
55			
56			PreparedStatement update = conn.prepareStatement ( "UPDATE stebuklas set last='boboz' where numbers =7");
57			
58			update.executeUpdate();
59		}
60		catch(Exception e){ System.out.println(e); } 
61		
62		System.out.println ("enri was replaced (updated)"); ////
63		
64	}
65	
66
67	public static void createTable () throws Exception {  // CREATE CREATE NEW TABLET
68		
69		try {
70			
71			Connection conn = DriverManager.getConnection(url,username,password);
72			
73			PreparedStatement create = conn.prepareStatement("CREATE TABLE IF NOT EXISTS stebuklas "
74					+ "( first varchar(253), "
75					+ "last varchar(250),"
76					+ "numbers integer(50) )");
77			create.executeUpdate();
78			
79		}
80		
81		catch(Exception e){ System.out.println(e); } 
82		
83		finally { System.out.println ("table was madee"); } ////
84		
85	}
86	
87		
88	public static void post () throws Exception {    // INSERT INSERT VALUES
89		
90		String var1 = "enri";
91		String var2 = "lerp";
92		double var3 = 7;
93		
94		try {
95			Connection conn = DriverManager.getConnection(url,username,password);
96			PreparedStatement posted = conn.prepareStatement (" INSERT INTO stebuklas "
97					+ "(first,last,numbers) VALUES  ('"+var1+"', '"+var2+"', '"+var3+"')");
98		
99			posted.executeUpdate ();
100			posted.executeUpdate ();
101		
102		}
103		catch(Exception e){ System.out.println(e); } 
104		finally {System.out.println ("values inserted to the table.");} //////
105		
106		
107	}
108	
109	
110	public static void get() throws Exception { // SELECT SELECT SELECT
111		try{
112			Connection conn = DriverManager.getConnection(url,username,password);
113			PreparedStatement statement = conn.prepareStatement("SELECT * FROM stebuklas LIMIT 2");
114			PreparedStatement stat = conn.prepareStatement("SELECT * FROM stebuklas LIMIT 3");
115			
116			ResultSet result = statement.executeQuery ();
117			ResultSet res = stat.executeQuery ();
118			
119			while  (result.next() ) {
120				
121				System.out.println ( result.getString("first") );
122				
123			}
124			
125			
126			while ( res.next() ) {
127			
128				System.out.println ( res.getInt("numbers") );
129			
130			}
131				
132		}
133		catch(Exception e){ System.out.println(e); }
134			
135	}
136	
137	
138	
139}