public override object DoWorkInCurrentTransaction(ISessionImplementor session, DbConnection conn,
DbTransaction transaction)
{
long result;
int rows;
do
{
//the loop ensure atomicitiy of the
//select + update even for no transaction
//or read committed isolation level (needed for .net?)
var qps = conn.CreateCommand();
DbDataReader rs = null;
qps.CommandText = query;
qps.CommandType = CommandType.Text;
qps.Transaction = transaction;
PersistentIdGeneratorParmsNames.SqlStatementLogger.LogCommand("Reading high value:", qps, FormatStyle.Basic);
try
{
rs = qps.ExecuteReader();
if (!rs.Read())
{
var errFormat = string.IsNullOrEmpty(whereClause)
? "could not read a hi value - you need to populate the table: {0}"
: "could not read a hi value from table '{0}' using the where clause ({1})- you need to populate the table.";
log.Error(errFormat, tableName, whereClause);
throw new IdentifierGenerationException(string.Format(errFormat, tableName, whereClause));
}
result = Convert.ToInt64(columnType.Get(rs, 0, session));
}
catch (Exception e)
{
log.Error(e, "could not read a hi value");
throw;
}
finally
{
if (rs != null)
{
rs.Close();
}
qps.Dispose();
}
var ups = session.Factory.ConnectionProvider.Driver.GenerateCommand(CommandType.Text, updateSql, parameterTypes);
ups.Connection = conn;
ups.Transaction = transaction;
try
{
columnType.Set(ups, result + 1, 0, session);
columnType.Set(ups, result, 1, session);
PersistentIdGeneratorParmsNames.SqlStatementLogger.LogCommand("Updating high value:", ups, FormatStyle.Basic);
rows = ups.ExecuteNonQuery();
}
catch (Exception e)
{
log.Error(e, "could not update hi value in: {0}", tableName);
throw;
}
finally
{
ups.Dispose();
}
}while (rows == 0);
return(result);
}
