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1 package org.ashkelon;
2
3 import java.sql.Connection  ;
4 import java.sql.PreparedStatement ;
5 import java.sql.SQLException ;
6
7 import org.ashkelon.db.DBMgr;
8 import org.ashkelon.util.Logger;
9
10
11
14 public class AncestorPopulator
15 {
16
17 public AncestorPopulator() throws SQLException
18 {
19 DBMgr mgr = DBMgr.getInstance();
20 Connection conn = mgr.getConnection();
21
22 Logger logger = Logger.getInstance();
23 logger.setTraceLevel(Logger.DEBUG);
24
25 String sql = "DELETE FROM CLASS_ANCESTORS";
26 PreparedStatement pstmt = conn.prepareStatement(sql);
27 int numAffected = pstmt.executeUpdate();
28 logger.debug("cleared ancestor table, "+numAffected+" records deleted");
29
30 sql = "INSERT INTO CLASS_ANCESTORS SELECT CLASSID, SUPERCLASSID, 1 FROM SUPERCLASS WHERE SUPERCLASSID IS NOT NULL";
31 pstmt = conn.prepareStatement(sql);
32 numAffected = pstmt.executeUpdate();
33
34 int nextLevel = 2;
35 int previousLevel = 1;
36
37 while (true)
38 {
39 sql = "DELETE FROM TEMP_DELTA";
40 pstmt = conn.prepareStatement(sql);
41 pstmt.executeUpdate();
42
43 sql = "INSERT INTO TEMP_DELTA SELECT A.CLASSID, C.SUPERCLASSID, "+nextLevel+
44 " FROM CLASS_ANCESTORS A, SUPERCLASS C WHERE A.SUPERCLASSID = C.CLASSID AND A.HIERARCHY = " + previousLevel
45 + " AND C.SUPERCLASSID IS NOT NULL";
46 logger.debug("sql: "+sql);
47 pstmt = conn.prepareStatement(sql);
48 numAffected = pstmt.executeUpdate();
49
50 logger.debug("pass # "+previousLevel+": inserted "+numAffected+" records");
51
52 if (numAffected == 0)
53 break;
54
55 sql = "INSERT INTO CLASS_ANCESTORS SELECT CLASSID, SUPERCLASSID, HIERARCHY FROM TEMP_DELTA";
56 pstmt = conn.prepareStatement(sql);
57 pstmt.executeUpdate();
58
59 previousLevel = nextLevel;
60 nextLevel++;
61 }
62
63 pstmt.close();
64
65 mgr.releaseConnection(conn);
66 mgr = null;
67 }
68
69 public static void main(String args[]) throws Exception
70 {
71 new AncestorPopulator();
72 }
73
74 }
75 |
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