protected void updateRequestTable() throws SQLException {
    dbAccessor.addColumn(REQUEST_TABLE, new DBAccessor.DBColumnInfo(REQUEST_USER_NAME_COLUMN, String.class, 255));
  }
Update the <code>adminprivilege</code> table to ensure records for the same username but different user
records are referencing the main user record. Duplicate records will be be ignored when updating
the <code>adminprivilege</code> table.
<p>
If <code>UserA:LOCAL</code>, <code>usera:LOCAL</code> and <code>usera:LDAP</code> are assigned
to <code>Role1</code>, the three <code>adminprivilege</code> records will be merged into a single
record for <code>usera</code>.
<p>
This method may be executed multiple times and will yield the same results each time.

@throws SQLException if an error occurs while executing SQL statements
ambari-server/src/main/java/org/apache/ambari/server/upgrade/UpgradeCatalog270.java