NHibernate HiLo - new column per entity and HiLo catches - nhibernate

Question

I'm currently using the hilo id generator for my classes but have just been using the minimal of settings eg
<class name="ClassA">
<id name="Id" column="id" unsaved-value="0">
<generator class="hilo" />
</id>
...
But should I really be specifying a new column for NHibernate to use foreach entity and providing it with a max lo?
<class name="ClassA">
<id name="Id" column="id" unsaved-value="0">
<generator class="hilo">
<param name="table">hibernate_unique_key</param>
<param name="column">classA_nexthi</param>
<param name="max_lo">20</param>
</generator>
</id>
...
<class name="ClassB">
<id name="Id" column="id" unsaved-value="0">
<generator class="hilo">
<param name="table">hibernate_unique_key</param>
<param name="column">classB_nexthi</param>
<param name="max_lo">20</param>
</generator>
</id>
...
Also I've noticed that when I do the above the SchemaExport will not create all the columns - only classB_nexthi, is there something else I'm doing wrong.

Answer 1

I asked this question again but in the nhusers group, see here for response i got

Answer 2

I did and maybe a little bit dirty for the moment but anyway:
public class TableHiLoGeneratorWithMultipleColumns : NHibernate.Id.TableHiLoGenerator
{
static HashSet<string> tables = new HashSet<string>();
public override void Configure(IType type, IDictionary<string, string> parms, Dialect dialect)
{
string table;
if (parms.ContainsKey("target_table"))
{
table = parms["target_table"];
tables.Add(table);
parms["column"] = string.Format("{0}_{1}", DefaultColumnName, table);
}
base.Configure(type, parms, dialect);
}
public override string[] SqlCreateStrings(Dialect dialect)
{
string createTableTemplate = "create table " + DefaultTableName + "({0})";
string insertInitialValuesTemplate = "insert into " + DefaultTableName + "({0})" + " values ( {1} )";
StringBuilder createTables = new StringBuilder();
StringBuilder columns = new StringBuilder();
StringBuilder inserts = new StringBuilder();
StringBuilder initialInsert = new StringBuilder();
StringBuilder insertsValues = new StringBuilder();
foreach (string table in tables)
{
columns.AppendFormat("{0}_{1} {2},", DefaultColumnName, table, dialect.GetTypeName(columnSqlType));
inserts.AppendFormat("{0}_{1},", DefaultColumnName, table);
insertsValues.Append("1, ");
}
columns.Remove(columns.Length - 1, 1);
inserts.Remove(inserts.Length - 1, 1);
createTables.AppendFormat(createTableTemplate, columns);
insertsValues.Remove(insertsValues.Length - 2, 2);
initialInsert.AppendFormat(insertInitialValuesTemplate, inserts, insertsValues);
return new[] { createTables.ToString(), initialInsert.ToString() };
}
}