Speedup patch for getTables() and getIndexInfo()

Hi !!

The following patch speeds up the queries in getTables() and
getIndexInfo(). It replaces the looping of queries with a simple join
operation. Patch is against the current CVS (2002-09-08).

- Panu

PS. Tested against PostgreSQL 7.1.2 and PostgreSQL 7.2.1 databases

--------------------------------------------------------------------------

--- AbstractJdbc1DatabaseMetaData.java.org Sun Sep 8 20:58:57 2002
+++ AbstractJdbc1DatabaseMetaData.java Sun Sep 8 21:02:58 2002
@@ -1836,7 +1836,9 @@
f[4] = new Field(connection, "REMARKS", iVarcharOid, NAME_SIZE);

// Now form the query
- StringBuffer sql = new StringBuffer("select relname,oid,relkind from
pg_class where (");
+ StringBuffer sql = new
StringBuffer(connection.haveMinimumServerVersion("7.2") ?
+ "select relname,oid,relkind,obj_description(oid,'pg_class') from
pg_class where (" :
+ "select c.relname,c.oid,c.relkind,d.description from pg_class c
left outer join pg_description d on (d.objoid = c.oid) where (" );

boolean notFirst = false;
for (int i = 0;i < types.length;i++)
@@ -1863,24 +1865,6 @@
while (r.next())
{
byte[][] tuple = new byte[5][0];
-
- // Fetch the description for the table (if any)
- String getDescriptionStatement =
- connection.haveMinimumServerVersion("7.2") ?
- "select obj_description(" + r.getInt(2) + ",'pg_class')" :
- "select description from pg_description where objoid=" + r.getInt(2);
-
- java.sql.ResultSet dr = connection.ExecSQL(getDescriptionStatement);
-
- byte remarks[] = null;
-
- if (((AbstractJdbc1ResultSet)dr).getTupleCount() == 1)
- {
- dr.next();
- remarks = dr.getBytes(1);
- }
- dr.close();
-
String relKind;
switch (r.getBytes(3)[0])
{
@@ -1911,7 +1895,7 @@
tuple[1] = null; // Schema name
tuple[2] = r.getBytes(1); // Table name
tuple[3] = (relKind == null) ? null : relKind.getBytes(); // Table type
- tuple[4] = remarks; // Remarks
+ tuple[4] = r.getBytes(4); //Remarks
v.addElement(tuple);
}
r.close();
@@ -3096,8 +3080,8 @@
"x.indkey, " +
"c.reltuples, " +
"c.relpages, " +
- "x.indexrelid " +
- "FROM pg_index x, pg_class c, pg_class i, pg_am a " +
+ "b.attname " +
+ "FROM pg_index x left outer join pg_attribute b on (x.indexrelid
= b.attrelid), pg_class c, pg_class i, pg_am a " +
"WHERE ((c.relname = '" + tableName.toLowerCase() + "') " +
" AND (c.oid = x.indrelid) " +
" AND (i.oid = x.indexrelid) " +
@@ -3118,7 +3102,6 @@
{
columnOrdinals[o++] = Integer.parseInt(stok.nextToken());
}
- java.sql.ResultSet columnNameRS = connection.ExecSQL("select a.attname
FROM pg_attribute a WHERE a.attrelid = " + r.getInt(9));
for (int i = 0; i < columnOrdinals.length; i++)
{
byte [] [] tuple = new byte [13] [];
@@ -3134,14 +3117,7 @@
Integer.toString(java.sql.DatabaseMetaData.tableIndexHashed).getBytes()
:
Integer.toString(java.sql.DatabaseMetaData.tableIndexOther).getBytes();
tuple[7] = Integer.toString(i + 1).getBytes();
- if (columnNameRS.next())
- {
- tuple[8] = columnNameRS.getBytes(1);
- }
- else
- {
- tuple[8] = "".getBytes();
- }
+ tuple[8] = r.getBytes(9);
tuple[9] = null; // sort sequence ???
tuple[10] = r.getBytes(7); // inexact
tuple[11] = r.getBytes(8);