fix: resultsets should be updateable if there is a unique constraint on the table fixes issue #2196

pgjdbc/src/main/java/org/postgresql/jdbc/PgDatabaseMetaData.java

@@ -2170,6 +2170,49 @@ public ResultSet getPrimaryKeys(@Nullable String catalog, @Nullable String schem
     return createMetaDataStatement().executeQuery(sql);
   }
 
+  /*
+  This is for internal use only to see if a resultset is updateable.
+  Unique keys can also be used so we add them to the query.
+   */
+  protected ResultSet getPrimaryUniqueKeys(@Nullable String catalog, @Nullable String schema, String table)
+      throws SQLException {
+    String sql;
+    sql = "SELECT NULL AS TABLE_CAT, n.nspname AS TABLE_SCHEM, "
+        + "  ct.relname AS TABLE_NAME, a.attname AS COLUMN_NAME, "
+        + "  (information_schema._pg_expandarray(i.indkey)).n AS KEY_SEQ, ci.relname AS PK_NAME, "
+        + "  information_schema._pg_expandarray(i.indkey) AS KEYS, a.attnum AS A_ATTNUM "
+        + "FROM pg_catalog.pg_class ct "
+        + "  JOIN pg_catalog.pg_attribute a ON (ct.oid = a.attrelid) "
+        + "  JOIN pg_catalog.pg_namespace n ON (ct.relnamespace = n.oid) "
+        + "  JOIN pg_catalog.pg_index i ON ( a.attrelid = i.indrelid) "
+        + "  JOIN pg_catalog.pg_class ci ON (ci.oid = i.indexrelid) "
+        + "WHERE true ";
+
+    if (schema != null && !schema.isEmpty()) {
+      sql += " AND n.nspname = " + escapeQuotes(schema);
+    }
+
+    if (table != null && !table.isEmpty()) {
+      sql += " AND ct.relname = " + escapeQuotes(table);
+    }
+
+    sql += " AND (i.indisprimary or i.indisunique) ";
+    sql = "SELECT "
+        + "       result.TABLE_CAT, "
+        + "       result.TABLE_SCHEM, "
+        + "       result.TABLE_NAME, "
+        + "       result.COLUMN_NAME, "
+        + "       result.KEY_SEQ, "
+        + "       result.PK_NAME "
+        + "FROM "
+        + "     (" + sql + " ) result"
+        + " where "
+        + " result.A_ATTNUM = (result.KEYS).x ";
+    sql += " ORDER BY result.table_name, result.pk_name, result.key_seq";
+
+    return createMetaDataStatement().executeQuery(sql);
+  }
+
   /**
    * @param primaryCatalog primary catalog
    * @param primarySchema primary schema

pgjdbc/src/main/java/org/postgresql/jdbc/PgResultSet.java

@@ -1646,7 +1646,7 @@ boolean isUpdateable() throws SQLException {
     @Nullable String[] s = quotelessTableName(castNonNull(tableName));
     String quotelessTableName = castNonNull(s[0]);
     @Nullable String quotelessSchemaName = s[1];
-    java.sql.ResultSet rs = connection.getMetaData().getPrimaryKeys("",
+    java.sql.ResultSet rs = ((PgDatabaseMetaData)connection.getMetaData()).getPrimaryUniqueKeys("",
         quotelessSchemaName, quotelessTableName);
 
     while (rs.next()) {

pgjdbc/src/test/java/org/postgresql/test/jdbc2/UpdateableResultTest.java

@@ -56,6 +56,8 @@ public void setUp() throws Exception {
     // put some dummy data into second
     st2.execute("insert into second values (1,'anyvalue' )");
     st2.close();
+    TestUtil.createTable(con, "uniqueconstraint", "u1 int unique, name1 text");
+    TestUtil.execute("insert into uniqueconstraint values (1, 'dave')", con);
 
   }
 
@@ -68,6 +70,7 @@ public void tearDown() throws SQLException {
     TestUtil.dropTable(con, "stream");
     TestUtil.dropTable(con, "nopkmulticol");
     TestUtil.dropTable(con, "booltable");
+    TestUtil.dropTable(con, "uniqueconstraint");
     super.tearDown();
   }
 
@@ -703,4 +706,16 @@ public void testOidUpdatable() throws Exception {
     rs.close();
     st.close();
   }
+
+  @Test
+  public void testUniqueUpdatable() throws Exception {
+    Statement st = con.createStatement(ResultSet.TYPE_SCROLL_INSENSITIVE,
+        ResultSet.CONCUR_UPDATABLE);
+    ResultSet rs = st.executeQuery("SELECT * from uniqueconstraint");
+    assertTrue(rs.next());
+    assertTrue(rs.first());
+    rs.updateString("name1", "bob");
+    rs.close();
+    st.close();
+  }
 }