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comparison example/SQLcopyinto.java @ 0:a5a898f6886c

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Copy of MonetDB java directory changeset e6e32756ad31.
author Sjoerd Mullender <sjoerd@acm.org>
date Wed, 21 Sep 2016 09:34:48 +0200 (2016-09-21)
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children f1de7262d8d9 b9b35ca2eec2
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-1:000000000000 0:a5a898f6886c
1 /*
2 * This Source Code Form is subject to the terms of the Mozilla Public
3 * License, v. 2.0. If a copy of the MPL was not distributed with this
4 * file, You can obtain one at http://mozilla.org/MPL/2.0/.
5 *
6 * Copyright 1997 - July 2008 CWI, August 2008 - 2016 MonetDB B.V.
7 */
8
9 import java.sql.*;
10 import java.io.*;
11 import java.util.*;
12 import nl.cwi.monetdb.mcl.net.*;
13 import nl.cwi.monetdb.mcl.io.*;
14
15 /**
16 * This example demonstrates how the MonetDB JDBC driver can facilitate
17 * in performing COPY INTO sequences. This is mainly meant to show how
18 * a quick load can be performed from Java.
19 *
20 * @author Fabian Groffen
21 */
22
23 public class SQLcopyinto {
24 public static void main(String[] args) throws Exception {
25 // make sure the driver is loaded
26 Class.forName("nl.cwi.monetdb.jdbc.MonetDriver");
27 // request a connection suitable for Monet from the driver manager
28 // note that the database specifier is currently not implemented, for
29 // Monet itself can't access multiple databases.
30 // turn on debugging
31 Connection con = DriverManager.getConnection("jdbc:monetdb://localhost/database", "monetdb", "monetdb");
32
33 // get a statement to execute on
34 Statement stmt = con.createStatement();
35
36 String query = "CREATE TABLE example (id int, val varchar(24))";
37 try {
38 stmt.execute(query);
39 } catch (SQLException e) {
40 System.out.println(query + ": " + e.getMessage());
41 System.exit(1);
42 }
43
44 // now create a connection manually to perform a load, this can
45 // of course also be done simultaneously with the JDBC
46 // connection being kept connected
47
48 MapiSocket server = new MapiSocket();
49
50 server.setDatabase("database");
51 server.setLanguage("sql");
52
53 try {
54 List warning =
55 server.connect("localhost", 50000, "monetdb", "monetdb");
56 if (warning != null) {
57 for (Iterator it = warning.iterator(); it.hasNext(); ) {
58 System.out.println(it.next().toString());
59 }
60 }
61
62 BufferedMCLReader in = server.getReader();
63 BufferedMCLWriter out = server.getWriter();
64
65 String error = in.waitForPrompt();
66 if (error != null)
67 throw new Exception(error);
68
69 query = "COPY INTO example FROM STDIN USING DELIMITERS ',','\\n';";
70 // the leading 's' is essential, since it is a protocol
71 // marker that should not be omitted, likewise the
72 // trailing semicolon
73 out.write('s');
74 out.write(query);
75 out.newLine();
76 for (int i = 0; i < 100; i++) {
77 out.write("" + i + ",val_" + i);
78 out.newLine();
79 }
80 out.writeLine(""); // need this one for synchronisation over flush()
81 error = in.waitForPrompt();
82 if (error != null)
83 throw new Exception(error);
84 // disconnect from server
85 server.close();
86 } catch (IOException e) {
87 System.err.println("unable to connect: " + e.getMessage());
88 System.exit(-1);
89 } catch (Exception e) {
90 System.err.println(e.getMessage());
91 System.exit(-1);
92 }
93
94 query = "SELECT COUNT(*) FROM example";
95 ResultSet rs = null;
96 try {
97 rs = stmt.executeQuery(query);
98 } catch (SQLException e) {
99 System.out.println(query + ": " + e.getMessage());
100 System.exit(1);
101 }
102 if (rs != null && rs.next())
103 System.out.println(rs.getString(1));
104
105 // free resources, close the statement
106 stmt.close();
107 // close the connection with the database
108 con.close();
109
110 }
111 }