Description:
The following patch fixes two problems with DataBaseMetaData.java. It also fixes a
problem with the corresponding MetaDataTest.
The problems were:
1. DataBasemetaData.getCrossReference() never returned any rows ( against mysqld Ver
4.0.15-max-debug for Win95/Win98 on i32)
2. DataBasemetaData.extractForeignKeyFromCreateTable() was looping over tables, and
creating a statement each iteration, but only closing the last statement.
The latter error caused MetadataTest.testForeignKeys() to fail with a concurrency
exception. Fixing that error enabled the test to pass, even though bug 1 was still
present. So this patch adds a check to the test to ensure that getCrossReference() (as
well as getImportedKeys() and getExportedKeys()) return the expected number of rows.
The problem with getCrossReference() was the way it looks for the FOREIGN KEY declaration
in the result from SHOW CREATE TABLE. It was searching for a line beginning with the
string "FOREIGN KEY". But MySQL 4.0.15 is returning a line like this for the FK:
CONSTRAINT `0_17254` FOREIGN KEY (`r`) REFERENCES `resource` (`locator`)
So I changed the detection to call indexOf("FOREIGN KEY"). This strategy ought to be
compatible with any version of MySQL that does return the line beginning with "FOREIGN
KEY". There is a vulnerability if other possible lines can constain the substring
"FOREIGN KEY"; I don't know if that can ever be the case.
How to repeat:
The patch in "suggested fix" patches the MetadataTest to demonstrate the bug. You would
have to apply only that one patch and not the other one in that patchfile, that fixes the
bug.
Suggested fix:
diff -x '*.class' -Naur
mysql-connector-java-3.1.0-alpha/com/mysql/jdbc/DatabaseMetaData.java
mysql-connector-java-3.1.0-alpha-FIX/com/mysql/jdbc/DatabaseMetaData.java
--- mysql-connector-java-3.1.0-alpha/com/mysql/jdbc/DatabaseMetaData.java 2003-02-17
11:28:00.000000000 -0600
+++ mysql-connector-java-3.1.0-alpha-FIX/com/mysql/jdbc/DatabaseMetaData.java 2003-11-23
12:17:12.921777600 -0600
@@ -4926,7 +4926,11 @@
while (lineTokenizer.hasMoreTokens()) {
String line = lineTokenizer.nextToken().trim();
- if (line.startsWith("FOREIGN KEY")) {
+ //if (line.startsWith("FOREIGN KEY")) {
+ int position = line.indexOf("FOREIGN KEY") ;
+ if ( position>= 0) {
+ // Position start of string at "FOREIGN KEY"
+ line = line.substring(position);
if (line.endsWith(",")) {
line = line.substring(0, line.length() - 1);
}
@@ -5063,6 +5067,9 @@
while (rs.next()) {
extractForeignKeyForTable(rows, rs, catalog);
}
+
+ stmt.close();
+ stmt = null;
}
} finally {
if (rs != null) {
diff -x '*.class' -Naur
mysql-connector-java-3.1.0-alpha/testsuite/simple/MetadataTest.java
mysql-connector-java-3.1.0-alpha-FIX/testsuite/simple/MetadataTest.java
--- mysql-connector-java-3.1.0-alpha/testsuite/simple/MetadataTest.java 2003-02-17
11:28:00.000000000 -0600
+++ mysql-connector-java-3.1.0-alpha-FIX/testsuite/simple/MetadataTest.java 2003-11-23
12:17:15.034816000 -0600
@@ -73,6 +73,7 @@
DatabaseMetaData dbmd = conn.getMetaData();
rs = dbmd.getImportedKeys(null, null, "child");
+ int count = 0;
while (rs.next()) {
String pkColumnName = rs.getString("PKCOLUMN_NAME");
String fkColumnName = rs.getString("FKCOLUMN_NAME");
@@ -82,11 +83,14 @@
assertTrue("Foreign Key not returned correctly ('" + fkColumnName
+ "' != 'parent_id_fk')",
fkColumnName.equalsIgnoreCase("parent_id_fk"));
+ count++;
}
-
+ assertEquals("getImportedKeys did not return 1 row", 1, count);
+
rs.close();
rs = dbmd.getExportedKeys(null, null, "parent");
+ count = 0;
while (rs.next()) {
String pkColumnName = rs.getString("PKCOLUMN_NAME");
String fkColumnName = rs.getString("FKCOLUMN_NAME");
@@ -102,13 +106,16 @@
"Foreign Key not returned correctly for getExportedKeys ('"
+ fkColumnName + "' != 'parent_id_fk')",
fkColumnName.equalsIgnoreCase("parent_id_fk"));
+ count++;
}
+ assertEquals("getExportedKeys did not return 1 row", 1, count);
rs.close();
rs = dbmd.getCrossReference(null, null, "cpd_foreign_3", null, null,
"cpd_foreign_4");
+ count = 0;
while (rs.next()) {
String pkColumnName = rs.getString("PKCOLUMN_NAME");
String pkTableName = rs.getString("PKTABLE_NAME");
@@ -122,11 +129,15 @@
System.out.println(pkTableName + "(" + pkColumnName + ") -> "
+ fkTableName + "(" + fkColumnName + ")");
+ count++;
}
+ assertEquals("getCrossReference did not return 2 rows", 2, count);
rs.close();
rs = dbmd.getImportedKeys(null, null, "fktable2");
+
+
}
/**
