Peter, can you comment on this patch?


> Hi all!
> 
> Attached is a patch that implements DatabaseMetaData.getIndexInfo()
> for the JDBC2 driver.  It also fixes a compile error under jikes by
> casting characters in case statements of a byte-compared switch to
> bytes.
> 
> A few notes on getIndexInfo():
> 
> 1.) getArray() is not implemented for the postgresql JDBC driver yet,
> so getIndexInfo() parses the pg_index.indkey field into separate
> integers by hand.
> 
> 2.) I have guessed that if pg_index.indisclustered is "false", then
> the index is "hashed"; if not, line 2561 of the resultant class
> should have "tableIndexOther" rather than "tableIndexHashed".
> 
> 3.) I didn't know what sort sequence (if any) was used in indexes, so
> I have set it to "null" (unknown) on line 2566.
> 
> 4.) For "CARDINALITY" (number of unique index items, the 11th field of
> the ResultSet returned by getIndexInfo()) I have used
> pg_classes.reltuples.
> 
> I have tested this method, but hardly extensively.  Is there a proper
> regression test suite for the JDBC driver that tests can be added to?
> 
> William
> -- 
> William Webber                               [EMAIL PROTECTED]
> Senior Programmer                             
> PeopleWeb Australia                          http://www.peopleweb.com

[ Attachment, skipping... ]


-- 
  Bruce Momjian                        |  http://candle.pha.pa.us
  [EMAIL PROTECTED]               |  (610) 853-3000
  +  If your life is a hard drive,     |  830 Blythe Avenue
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--- DatabaseMetaData.java.old   Thu Feb  1 14:28:09 2001
+++ DatabaseMetaData.java       Thu Feb  1 14:43:07 2001
@@ -1689,13 +1689,13 @@
 
        String relKind;
        switch (r.getBytes(3)[0]) {
-       case 'r':
+       case (byte) 'r':
            relKind = "TABLE";
            break;
-       case 'i':
+       case (byte) 'i':
            relKind = "INDEX";
            break;
-       case 'S':
+       case (byte) 'S':
            relKind = "SEQUENCE";
            break;
        default:
@@ -2515,11 +2515,10 @@
    * @return ResultSet each row is an index column description
    */
   // Implementation note: This is required for Borland's JBuilder to work
-  public java.sql.ResultSet getIndexInfo(String catalog, String schema, String table, 
boolean unique, boolean approximate) throws SQLException
+  public java.sql.ResultSet getIndexInfo(String catalog, String schema, String 
+tableName, boolean unique, boolean approximate) throws SQLException
   {
-    // for now, this returns an empty result set.
     Field f[] = new Field[13];
-    ResultSet r;       // ResultSet for the SQL query that we need to do
+    java.sql.ResultSet r;      // ResultSet for the SQL query that we need to do
     Vector v = new Vector();           // The new ResultSet tuple stuff
 
     f[0] = new Field(connection, "TABLE_CAT", iVarcharOid, 32);
@@ -2535,6 +2534,42 @@
     f[10] = new Field(connection, "CARDINALITY", iInt4Oid, 4);
     f[11] = new Field(connection, "PAGES", iInt4Oid, 4);
     f[12] = new Field(connection, "FILTER_CONDITION", iVarcharOid, 32);
+
+    r = connection.ExecSQL("select c.relname, x.indisunique, i.relname, 
+x.indisclustered, x.indkey, c.reltuples, c.relpages, c.oid FROM pg_index x, pg_class 
+c, pg_class i WHERE ((c.oid = x.indrelid) AND (i.oid = x.indexrelid) AND (c.relname = 
+'" + tableName.toLowerCase() + "')) ORDER BY x.indisunique DESC, x.indisclustered, 
+i.relname");  
+    while (r.next()) {
+        // indkey is an array of column ordinals (integers).  In the JDBC
+        // interface, this has to be separated out into a separate
+        // tuple for each indexed column.  Also, getArray() is not yet
+        // implemented for Postgres JDBC, so we parse by hand.
+        String columnOrdinalString = r.getString(5);
+        StringTokenizer stok = new StringTokenizer(columnOrdinalString);
+        int [] columnOrdinals = new int[stok.countTokens()];
+        int o = 0;
+        while (stok.hasMoreTokens()) {
+            columnOrdinals[o++] = Integer.parseInt(stok.nextToken());
+        }
+        for (int i = 0; i < columnOrdinals.length; i++) {
+            byte [] [] tuple = new byte [13] [];
+            tuple[0] = "".getBytes(); 
+            tuple[1] = "".getBytes();
+            tuple[2] = r.getBytes(1);
+            tuple[3] = r.getBoolean(2) ? "f".getBytes() : "t".getBytes();
+            tuple[4] = null;
+            tuple[5] = r.getBytes(3);
+            tuple[6] = r.getBoolean(4)
+                ? Integer.toString(tableIndexClustered).getBytes()
+                : Integer.toString(tableIndexHashed).getBytes(); // ??? I guess
+            tuple[7] = Integer.toString(i + 1).getBytes();
+            java.sql.ResultSet columnNameRS = connection.ExecSQL("select a.attname 
+FROM pg_attribute a, pg_class c WHERE (a.attnum = " + columnOrdinals[i] + ") AND 
+(a.attrelid = " + r.getInt(8) + ")");
+            columnNameRS.next();
+            tuple[8] = columnNameRS.getBytes(1);
+            tuple[9] = null;  // sort sequence ???
+            tuple[10] = r.getBytes(6);  // inexact
+            tuple[11] = r.getBytes(7);
+            tuple[12] = null;
+            v.addElement(tuple);
+        }
+    }
 
     return new ResultSet(connection, f, v, "OK", 1);
   }

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