[OJB-developers] JDBCAccess performance optimization

[Jakob B. <jbr...@ho...>]

hi,

the performance optimization in JDBCAccess crashes or at least slows down
QueryBySQL:

sql = "select * from tabPerson where name like '%er'";
query = new QueryBySQL(Person.class, sql);

in the above sample the sequence of the columns may not match the sequence
of the fields in the ClassDescriptor, that's why i
got the column id from the resultset  using findColumn().

static Object getObjectFromColumn(ResultSet rs, FieldDescriptor fld) throws
SQLException
{
    int jdbcType = fld.getColumnJdbcType();
    int columnId = fld.getColNo(); //rs.findColumn(fld.getColumnName());
//use columnId from rs BRJ
    return getObjectFromColumn(rs, jdbcType, columnId);
}

i do not know how much this lookup affects performance.
but for QueryBySQL it has a negative effect because the SqlBaseIterator may
get an
exception in the method getObjectFromResultSet() and therefore try to
retrieve the object via getObjectByIdentity().

jakob