MySQL Bugs: #51912: Passing NULL as cat. param to getProcedureColumns with !nullCatalogMeansCurrent

Bug #51912	Passing NULL as cat. param to getProcedureColumns with !nullCatalogMeansCurrent
Submitted:	10 Mar 2010 13:38	Modified:	20 Jul 2010 7:11
Reporter:	Tonci Grgin	Email Updates:
Status:	Closed	Impact on me:	None
Category:	Connector / J	Severity:	S3 (Non-critical)
Version:	5.1 branch	OS:	Any
Assigned to:	Tony Bedford	CPU Architecture:	Any

Description:
Working on Bug#51904 I found out that calling 
  this.rs = dbmd.getProcedureColumns(null, null, "%", null);
while nullCatalogMeansCurrent=false leads to crash...

For servers < 5.4 code goes to DataBaseMetadata.java, 	private void getCallStmtParameterTypes(String catalog, String procName,...
and to this code:
	String dbName = null;
	if (dotIndex != -1 && (dotIndex + 1) < procName.length()) {
		dbName = procName.substring(0, dotIndex);
		procName = procName.substring(dotIndex + 1);
	} else {
		dbName = catalog;
	}

Being that "catalog" passed is null this crashes the whole thing.

How to repeat:
    DatabaseMetaData dbmd = this.conn.getMetaData();
    System.out.println("\nCalling getProcedureColumns(null, null, \"%\", null)");
    this.rs = dbmd.getProcedureColumns(null, null, "%", null); //this.conn.getCatalog()

Suggested fix:
First of all, we need to decide here is null catalog to be supported with getProcedureColumns when nullCatalogMeansCurrent=false.
Then, we can fortify this particular part of code if needs be.

Mark?

Bug#52167 will be fixed together with this one.

Bug#51904 will be fixed together with this one.

Probably fixed Bug#51712 in process.

Bug#51712 is actually tested with regression test for Bug#41269 as, after fixing PROC_CAT parameter, they are the same.

Bug#51904 is fixed as a part of this bug report.

Regression test case added.

Pushed up to revision 918.

Final diff file

Attachment: df.txt (text/plain), 10.46 KiB.

An entry has been added to the 5.1.13 changelog:

Calling getProcedureColumns with null as the catalog parameter and the connection string option nullCatalogMeansCurrent set to false resulted in a crash.

Changelog entry has been updated:

The catalog parameter, PARAM_CAT, was not correctly processed when calling for metadata with getMetaData() on stored procedures. This was because PARAM_CAT was hardcoded in the code to NULL. In the case where nullcatalogmeanscurrent was true, which is its default value, a crash did not occur, but the meta data returned was for the stored procedures from the catalog currently attached to. If, however, nullcatalogmeanscurrent was set to false then a crash resulted.

Connector/J has been changed so that when NULL is passed as PARAM_CAT it will not crash when nullcatalogmeanscurrent is false, but rather iterate all catalogs in search of stored procedures. This means that PARAM_CAT is no longer hardcoded to NULL (see Bug#51904).

The test case for this bug lacks the code checking metadata from getProcedureColumns():

=== modified file 'src/testsuite/regression/MetaDataRegressionTest.java'
--- src/testsuite/regression/MetaDataRegressionTest.java	2010-03-24 10:19:08 +0000
+++ src/testsuite/regression/MetaDataRegressionTest.java	2010-07-16 05:23:09 +0000
@@ -2612,6 +2612,16 @@
 
         	DatabaseMetaData dbmd = overrideConn.getMetaData();
             this.rs = dbmd.getProcedureColumns(null, null, "%", null);
+            ResultSetMetaData rsmd = this.rs.getMetaData();
+
+            // remark (column 13) is empty, so can be skipped
+            for (int i = 1; i < 13; i++)
+            {
+                // skip PROCEDURE_SCHEM
+                if (i == 2)
+                    continue;
+                assertTrue(rsmd.getColumnDisplaySize(i) > 0);
+            }
             this.rs.close();
             
 		} finally {

Next, the fix has been discussed with Tonci. Because the length has been added for compatibility with ODBC it does not really matter what the actual length is (Tonci can correct the numbers):

=== modified file 'src/com/mysql/jdbc/DatabaseMetaData.java'
--- src/com/mysql/jdbc/DatabaseMetaData.java	2010-04-06 17:20:14 +0000
+++ src/com/mysql/jdbc/DatabaseMetaData.java	2010-07-16 05:24:32 +0000
@@ -4083,18 +4083,18 @@
 	protected Field[] createProcedureColumnsFields() {
 		Field[] fields = new Field[13];
 
-		fields[0] = new Field("", "PROCEDURE_CAT", Types.CHAR, 0);
+		fields[0] = new Field("", "PROCEDURE_CAT", Types.CHAR, 255);
 		fields[1] = new Field("", "PROCEDURE_SCHEM", Types.CHAR, 0);
-		fields[2] = new Field("", "PROCEDURE_NAME", Types.CHAR, 0);
-		fields[3] = new Field("", "COLUMN_NAME", Types.CHAR, 0);
-		fields[4] = new Field("", "COLUMN_TYPE", Types.CHAR, 0);
-		fields[5] = new Field("", "DATA_TYPE", Types.SMALLINT, 0);
-		fields[6] = new Field("", "TYPE_NAME", Types.CHAR, 0);
-		fields[7] = new Field("", "PRECISION", Types.INTEGER, 0);
-		fields[8] = new Field("", "LENGTH", Types.INTEGER, 0);
-		fields[9] = new Field("", "SCALE", Types.SMALLINT, 0);
-		fields[10] = new Field("", "RADIX", Types.SMALLINT, 0);
-		fields[11] = new Field("", "NULLABLE", Types.SMALLINT, 0);
+		fields[2] = new Field("", "PROCEDURE_NAME", Types.CHAR, 255);
+		fields[3] = new Field("", "COLUMN_NAME", Types.CHAR, 255);
+		fields[4] = new Field("", "COLUMN_TYPE", Types.CHAR, 255);
+		fields[5] = new Field("", "DATA_TYPE", Types.SMALLINT, 255);
+		fields[6] = new Field("", "TYPE_NAME", Types.CHAR, 255);
+		fields[7] = new Field("", "PRECISION", Types.INTEGER, 255);
+		fields[8] = new Field("", "LENGTH", Types.INTEGER, 255);
+		fields[9] = new Field("", "SCALE", Types.SMALLINT, 255);
+		fields[10] = new Field("", "RADIX", Types.SMALLINT, 255);
+		fields[11] = new Field("", "NULLABLE", Types.SMALLINT, 255);
 		fields[12] = new Field("", "REMARKS", Types.CHAR, 0);
 		return fields;
 	}

The proposed fix for src/com/mysql/jdbc/DatabaseMetaData.java is pushed 13 days ago in revno 956.