public void Visit(LimitNode node)
{
foreach (var inner in node.Inner)
{
inner.Accept(this);
}
}
/// <summary>
/// Creates a query tree for the given query elements
/// </summary>
/// <param name="match"><see cref="MatchNode"/> for matching log items</param>
/// <param name="parser"><see cref="IParser"/> for parsing log items</param>
/// <param name="filter">An <see cref="Expression"/> for filtering log items</param>
/// <param name="grouping">An enumerable of tuples of group names and grouping <see cref="Expression"/>s for grouping the log items</param>
/// <param name="selects">An enumerable of tuples of projection labels and <see cref="Expression"/>s for projecting log items</param>
/// <param name="order">An enumerable of tuples indicating sorting fields and sort order</param>
/// <param name="limit">The number of items to return</param>
/// <returns>A query tree for executing the query</returns>
private static Node CreateQueryTree(
MatchNode match,
IOption <Tuple <string, IParser> > parser,
IOption <Expression> filter,
IOption <IEnumerable <Tuple <string, Expression> > > grouping,
IOption <IEnumerable <Tuple <string, IAggregate> > > selects,
IOption <IEnumerable <Tuple <string, bool> > > order,
IOption <int> limit)
{
Node query = match;
if (!parser.IsEmpty)
{
query = new ParseNode(query, parser.Get().Item2, parser.Get().Item1);
}
if (!filter.IsEmpty)
{
query = new PredicateNode(query, filter.Get());
}
if (!grouping.IsEmpty)
{
var keyNames = grouping.Get().Select(g => g.Item1).ToArray();
var keyExpressions = grouping.Get().Select(g => g.Item2).ToArray();
if (selects.IsEmpty)
{
query = new GroupByNode(query, keyNames, keyExpressions, new string[0], new IAggregate[0]);
}
else
{
var aggregateNames = selects.Get().Select(s => s.Item1).ToArray();
var aggregates = selects.Get().Select(s => s.Item2).ToArray();
query = new GroupByNode(query, keyNames, keyExpressions, aggregateNames, aggregates);
}
}
else if (!selects.IsEmpty)
{
var aggregateNames = selects.Get().Select(s => s.Item1).ToArray();
var aggregates = selects.Get().Select(s => s.Item2).ToArray();
if (aggregates.All(a => a is ListAggregate))
{
query = new ProjectNode(query, aggregateNames, aggregates.Cast <ListAggregate>().Select(a => a.Expression).ToArray());
}
else
{
query = new AggregateNode(query, aggregateNames, aggregates);
}
}
if (!order.IsEmpty)
{
query = new OrderByNode(query, order.Get().Select(a => a.Item1).ToArray(), order.Get().Select(a => a.Item2).ToArray());
}
if (!limit.IsEmpty)
{
query = new LimitNode(query, limit.Get());
}
return(query);
}
public void Visit(LimitNode node)
{
node.Inner[0].Accept(this);
Items = Items.Take(node.Count);
}
public void Visit(LimitNode node)
{
node.Inner[0].Accept(this);
Tree = new LimitNode(Tree, node.Count);
}
public void Visit(LimitNode node)
{
node.Inner[0].Accept(this);
}
public void Visit(LimitNode node) => Format(node, $"Count = {node.Count}");
public void Visit(LimitNode node) => VisitInternal(node);
