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1
5 package org.h2.table;
6
7 import java.sql.Connection  ;
8 import java.sql.DatabaseMetaData ;
9 import java.sql.DriverManager ;
10 import java.sql.PreparedStatement ;
11 import java.sql.ResultSet ;
12 import java.sql.ResultSetMetaData ;
13 import java.sql.SQLException ;
14 import java.sql.Statement ;
15 import java.util.HashMap ;
16
17 import org.h2.engine.Session;
18 import org.h2.index.Index;
19 import org.h2.index.IndexType;
20 import org.h2.index.LinkedIndex;
21 import org.h2.message.Message;
22 import org.h2.result.Row;
23 import org.h2.schema.Schema;
24 import org.h2.util.JdbcUtils;
25 import org.h2.util.ObjectArray;
26 import org.h2.util.StringUtils;
27 import org.h2.value.DataType;
28
29
32
33 public class TableLink extends Table {
34
35 private String driver, url, user, password, originalTable;
36 private Connection conn;
37 private HashMap prepared = new HashMap ();
38 private ObjectArray indexes = new ObjectArray();
39
40 public TableLink(Schema schema, int id, String name, String driver, String url,
41 String user, String password, String originalTable) throws SQLException {
42 super(schema, id, name, false);
43 this.driver = driver;
44 this.url = url;
45 this.user = user;
46 this.password = password;
47 this.originalTable = originalTable;
48 try {
49 database.loadClass(driver);
50 } catch(ClassNotFoundException e) {
51 throw Message.getSQLException(Message.CLASS_NOT_FOUND_1, new String []{driver}, e);
52 }
53 conn = DriverManager.getConnection(url, user, password);
54 DatabaseMetaData meta = conn.getMetaData();
55 boolean storesLowerCase = meta.storesLowerCaseIdentifiers();
56 ResultSet rs = meta.getColumns(null, null, originalTable, null);
57 int i=0;
58 ObjectArray columnList = new ObjectArray();
59 HashMap columnMap = new HashMap ();
60 while(rs.next()) {
61 String n = rs.getString("COLUMN_NAME");
62 if(storesLowerCase && n.equals(StringUtils.toLowerEnglish(n))) {
63 n = StringUtils.toUpperEnglish(n);
64 }
65 int sqlType = rs.getInt("DATA_TYPE");
66 long precision = rs.getInt("COLUMN_SIZE");
67 int scale = rs.getInt("DECIMAL_DIGITS");
68 int type = DataType.convertSQLTypeToValueType(sqlType);
69 precision = Math.max(precision, DataType.getDataType(type).defaultPrecision);
70 Column col = new Column(n, type, precision, scale);
71 col.setTable(this, i++);
72 columnList.add(col);
73 columnMap.put(n, col);
74 }
75 if(columnList.size()==0) {
76 Statement stat = null;
77 try {
78 stat = conn.createStatement();
79 rs = stat.executeQuery("SELECT * FROM " + originalTable + " T WHERE 1=0");
80 ResultSetMetaData rsm = rs.getMetaData();
81 for(i=0; i<rsm.getColumnCount();) {
82 String n = rsm.getColumnName(i+1);
83 if(storesLowerCase && n.equals(StringUtils.toLowerEnglish(n))) {
84 n = StringUtils.toUpperEnglish(n);
85 }
86 int sqlType = rsm.getColumnType(i+1);
87 long precision = rsm.getPrecision(i+1);
88 int scale = rsm.getScale(i+1);
89 int type = DataType.convertSQLTypeToValueType(sqlType);
90 precision = Math.max(precision, DataType.getDataType(type).defaultPrecision);
91 Column col = new Column(n, type, precision, scale);
92 col.setTable(this, i++);
93 columnList.add(col);
94 columnMap.put(n, col);
95 }
96 } catch(SQLException e) {
97 throw Message.getSQLException(Message.TABLE_OR_VIEW_NOT_FOUND_1, new String []{originalTable}, e);
98 } finally {
99 JdbcUtils.closeSilently(stat);
100 }
101 }
102 Column[] cols = new Column[columnList.size()];
103 columnList.toArray(cols);
104 setColumns(cols);
105 Index index = new LinkedIndex(this, id, cols, IndexType.createNonUnique(false));
106 indexes.add(index);
107 rs = meta.getPrimaryKeys(null, null, originalTable);
108 String pkName = "";
109 ObjectArray list;
110 if (rs.next()) {
111 list = new ObjectArray();
113 do {
114 int idx = rs.getInt("KEY_SEQ");
115 if(pkName == null) {
116 pkName = rs.getString("PK_NAME");
117 }
118 while (list.size() < idx) {
119 list.add(null);
120 }
121 String col = rs.getString("COLUMN_NAME");
122 Column column = (Column) columnMap.get(col);
123 list.set(idx - 1, column);
124 } while (rs.next());
125 addIndex(list, IndexType.createPrimaryKey(false, false));
126 }
127 try {
128 rs = meta.getIndexInfo(null, null, originalTable, false, false);
129 } catch(SQLException e) {
130 rs = null;
132 }
133 String indexName = null;
134 list = new ObjectArray();
135 IndexType indexType = null;
136 while (rs != null && rs.next()) {
137 String newIndex = rs.getString("INDEX_NAME");
138 if (pkName.equals(newIndex)) {
139 continue;
140 }
141 if (indexName != null && !indexName.equals(newIndex)) {
142 addIndex(list, indexType);
143 indexName = null;
144 }
145 if (indexName == null) {
146 indexName = newIndex;
147 list.clear();
148 }
149 boolean unique = !rs.getBoolean("NON_UNIQUE");
150 indexType = unique ? IndexType.createUnique(false, false): IndexType.createNonUnique(false);
151 String col = rs.getString("COLUMN_NAME");
152 Column column = (Column) columnMap.get(col);
153 list.add(column);
154 }
155 if (indexName != null) {
156 addIndex(list, indexType);
157 }
158 }
159
160 private void addIndex(ObjectArray list, IndexType indexType) {
161 Column[] cols = new Column[list.size()];
162 list.toArray(cols);
163 Index index = new LinkedIndex(this, 0, cols, indexType);
164 indexes.add(index);
165 }
166
167 public String getCreateSQL() {
168 StringBuffer buff = new StringBuffer ();
169 buff.append("CREATE LINKED TABLE ");
170 buff.append(getSQL());
171 if(comment != null) {
172 buff.append(" COMMENT ");
173 buff.append(StringUtils.quoteStringSQL(comment));
174 }
175 buff.append("(");
176 buff.append(StringUtils.quoteStringSQL(driver));
177 buff.append(", ");
178 buff.append(StringUtils.quoteStringSQL(url));
179 buff.append(", ");
180 buff.append(StringUtils.quoteStringSQL(user));
181 buff.append(", ");
182 buff.append(StringUtils.quoteStringSQL(password));
183 buff.append(", ");
184 buff.append(StringUtils.quoteStringSQL(originalTable));
185 buff.append(")");
186 return buff.toString();
187 }
188
189 public Index addIndex(Session session, String indexName, int indexId, Column[] cols, IndexType indexType, int headPos, String comment) throws SQLException {
190 throw Message.getUnsupportedException();
191 }
192
193 public void lock(Session session, boolean exclusive) throws SQLException {
194 }
196
197 public boolean isLockedExclusively() {
198 return false;
199 }
200
201 public Index getScanIndex(Session session) {
202 return (Index) indexes.get(0);
203 }
204
205 public void removeRow(Session session, Row row) throws SQLException {
206 getScanIndex(session).remove(session, row);
207 }
208
209 public void addRow(Session session, Row row) throws SQLException {
210 getScanIndex(session).add(session, row);
211 }
212
213 public void close(Session session) throws SQLException {
214 if(conn != null) {
215 try {
216 conn.close();
217 } finally {
218 conn = null;
219 }
220 }
221 }
222
223 public int getRowCount() throws SQLException {
224 PreparedStatement prep = getPreparedStatement("SELECT COUNT(*) FROM "+originalTable);
225 ResultSet rs = prep.executeQuery();
226 rs.next();
227 int count = rs.getInt(1);
228 rs.close();
229 return count;
230 }
231
232 public String getOriginalTable() {
233 return originalTable;
234 }
235
236 public PreparedStatement getPreparedStatement(String sql) throws SQLException {
237 PreparedStatement prep = (PreparedStatement ) prepared.get(sql);
238 if(prep==null) {
239 prep = conn.prepareStatement(sql);
240 prepared.put(sql, prep);
241 }
242 return prep;
243 }
244
245 public void unlock(Session s) {
246 }
248
249 public void checkRename() throws SQLException {
250 }
251
252 public void checkSupportAlter() throws SQLException {
253 throw Message.getUnsupportedException();
254 }
255
256 public void truncate(Session session) throws SQLException {
257 throw Message.getUnsupportedException();
258 }
259
260 public boolean canGetRowCount() {
261 return true;
262 }
263
264 public boolean canDrop() {
265 return true;
266 }
267
268 public String getTableType() {
269 return Table.TABLE_LINK;
270 }
271
272 public void removeChildrenAndResources(Session session) throws SQLException {
273 super.removeChildrenAndResources(session);
274 close(session);
275 driver = null;
276 url = user = password = originalTable = null;
277 conn = null;
278 prepared = null;
279 invalidate();
280 }
281
282 public ObjectArray getIndexes() {
283 return indexes;
284 }
285
286 public long getMaxDataModificationId() {
287 return Long.MAX_VALUE;
289 }
290
291 public Index getUniqueIndex() {
292 for(int i=0; i<indexes.size(); i++) {
293 Index idx = (Index) indexes.get(i);
294 if(idx.getIndexType().isUnique()) {
295 return idx;
296 }
297 }
298 return null;
299 }
300
301 }
302 |
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