protected bool DetermineIsSeekable()
{
for (int index = 0; index < _conditions.Count; index++)
{
if ((_conditions[index].Count > 1) || (_conditions[index][0].Instruction != Instructions.Equal) || !_conditions[index][0].Argument.IsContextLiteral(0))
{
return(false);
}
}
Schema.KeyColumns keyColumns = new Schema.KeyColumns(null);
for (int index = 0; index < _conditions.Count; index++)
{
keyColumns.Add(_conditions[index].Column);
}
foreach (Schema.Key key in SourceTableVar.Keys)
{
if (!key.IsSparse && (key.Columns.Count == keyColumns.Count) && key.Columns.IsSupersetOf(keyColumns))
{
return(true);
}
}
return(false);
}
protected Schema.Order FindSeekOrder(Plan plan)
{
Schema.KeyColumns keyColumns = new Schema.KeyColumns(null);
for (int index = 0; index < _conditions.Count; index++)
{
keyColumns.Add(_conditions[index].Column);
}
foreach (Schema.Key key in SourceTableVar.Keys)
{
if (!key.IsSparse && (key.Columns.Count == keyColumns.Count) && key.Columns.IsSupersetOf(keyColumns))
{
return(Compiler.OrderFromKey(plan, key));
}
}
return(null);
}
