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1
5 package org.h2.index;
6
7 import java.sql.PreparedStatement  ;
8 import java.sql.ResultSet ;
9 import java.sql.SQLException ;
10
11 import org.h2.engine.Constants;
12 import org.h2.engine.Session;
13 import org.h2.message.Message;
14 import org.h2.result.Row;
15 import org.h2.result.SearchRow;
16 import org.h2.table.Column;
17 import org.h2.table.TableLink;
18 import org.h2.value.Value;
19 import org.h2.value.ValueNull;
20
21
24
25 public class LinkedIndex extends Index {
26
27 private TableLink link;
28 private String originalTable;
29
30 public LinkedIndex(TableLink table, int id, Column[] columns, IndexType indexType) {
31 super(table, id, null, columns, indexType);
32 link = table;
33 originalTable = link.getOriginalTable();
34 }
35
36 public String getCreateSQL() {
37 return null;
38 }
39
40 public void close(Session session) throws SQLException {
41 }
42
43 public void add(Session session, Row row) throws SQLException {
44 StringBuffer buff = new StringBuffer ("INSERT INTO ");
45 buff.append(originalTable);
46 buff.append(" VALUES(");
47 for(int i=0, j=0; i<row.getColumnCount(); i++) {
48 Value v = row.getValue(i);
49 if(j>0) {
50 buff.append(',');
51 }
52 j++;
53 if(v != null && v != ValueNull.INSTANCE) {
54 buff.append('?');
55 } else {
56 buff.append("NULL");
57 }
58 }
59 buff.append(')');
60 String sql = buff.toString();
61 try {
62 PreparedStatement prep = link.getPreparedStatement(sql);
63 for(int i=0, j=0; i<row.getColumnCount(); i++) {
64 Value v = row.getValue(i);
65 if(v != null && v != ValueNull.INSTANCE) {
66 v.set(prep, j+1);
67 j++;
68 }
69 }
70 prep.executeUpdate();
71 rowCount++;
72 } catch(SQLException e) {
73 throw Message.getSQLException(Message.ERROR_ACCESSING_LINKED_TABLE_1, new String []{sql}, e);
74 }
75 }
76
77 public void remove(Session session, Row row) throws SQLException {
78 StringBuffer buff = new StringBuffer ("DELETE FROM ");
79 buff.append(originalTable);
80 buff.append(" WHERE ");
81 for(int i=0; i<row.getColumnCount(); i++) {
82 if(i>0) {
83 buff.append("AND ");
84 }
85 buff.append(table.getColumn(i).getSQL());
86 buff.append("=? ");
87 }
88 String sql = buff.toString();
89 try {
90 PreparedStatement prep = link.getPreparedStatement(sql);
91 for(int i=0, j=0; i<row.getColumnCount(); i++) {
92 Value v = row.getValue(i);
93 if(v != null) {
94 v.set(prep, j+1);
95 j++;
96 }
97 }
98 prep.executeUpdate();
99 rowCount--;
100 } catch(SQLException e) {
101 throw Message.getSQLException(Message.ERROR_ACCESSING_LINKED_TABLE_1, new String []{sql}, e);
102 }
103 }
104
105 public Cursor find(Session session, SearchRow first, SearchRow last) throws SQLException {
106 StringBuffer buff = new StringBuffer ();
107 for(int i=0; first != null && i<first.getColumnCount(); i++) {
108 Value v = first.getValue(i);
109 if(v != null) {
110 if(buff.length() != 0) {
111 buff.append(" AND ");
112 }
113 buff.append(table.getColumn(i).getSQL());
114 buff.append(">=?");
115 }
116 }
117 for(int i=0; last != null && i<last.getColumnCount(); i++) {
118 Value v = last.getValue(i);
119 if(v != null) {
120 if(buff.length() != 0) {
121 buff.append(" AND ");
122 }
123 buff.append(table.getColumn(i).getSQL());
124 buff.append("<=?");
125 }
126 }
127 if(buff.length() > 0) {
128 buff.insert(0, " WHERE ");
129 }
130 buff.insert(0, "SELECT * FROM "+originalTable);
131 String sql = buff.toString();
132 try {
133 PreparedStatement prep = link.getPreparedStatement(sql);
134 int j=0;
135 for(int i=0; first != null && i<first.getColumnCount(); i++) {
136 Value v = first.getValue(i);
137 if(v != null) {
138 v.set(prep, j+1);
139 j++;
140 }
141 }
142 for(int i=0; last != null && i<last.getColumnCount(); i++) {
143 Value v = last.getValue(i);
144 if(v != null) {
145 v.set(prep, j+1);
146 j++;
147 }
148 }
149 ResultSet rs = prep.executeQuery();
150 return new LinkedCursor(table, rs, session);
151 } catch(SQLException e) {
152 throw Message.getSQLException(Message.ERROR_ACCESSING_LINKED_TABLE_1, new String []{sql}, e);
153 }
154 }
155
156 public int getLookupCost(int rowCount) {
157 for(int i=0, j = 1; ; i++) {
158 j *= 10;
159 if(j>rowCount) {
160 return i+1;
161 }
162 }
163 }
164
165 public int getCost(int[] masks) throws SQLException {
166 return 100 + getCostRangeIndex(masks, rowCount + Constants.COST_ROW_OFFSET);
167 }
168
169 public void remove(Session session) throws SQLException {
170 }
171
172 public void truncate(Session session) throws SQLException {
173 }
174
175 public void checkRename() throws SQLException {
176 throw Message.getUnsupportedException();
177 }
178
179 public boolean needRebuild() {
180 return false;
181 }
182
183 public boolean canGetFirstOrLast(boolean first) {
184 return false;
185 }
186
187 public Value findFirstOrLast(Session session, boolean first) throws SQLException {
188 throw Message.getUnsupportedException();
190 }
191
192 }
193 |
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