// Min/Max nodes can be either an aggregate or a per-row function depending on the number or arguments
private static void HandleMinMax(
string ident,
EsperEPL2GrammarParser.LibFunctionArgsContext ctxArgs,
IDictionary <ITree, ExprNode> astExprNodeMap)
{
// Determine min or max
var childNodeText = ident;
MinMaxTypeEnum minMaxTypeEnum;
var filtered = childNodeText.StartsWith("f");
if (childNodeText.ToLowerInvariant().Equals("min") || childNodeText.ToLowerInvariant().Equals("fmin"))
{
minMaxTypeEnum = MinMaxTypeEnum.MIN;
}
else if (childNodeText.ToLowerInvariant().Equals("max") || childNodeText.ToLowerInvariant().Equals("fmax"))
{
minMaxTypeEnum = MinMaxTypeEnum.MAX;
}
else
{
throw ASTWalkException.From("Uncountered unrecognized min or max node '" + ident + "'");
}
var args = Collections.GetEmptyList <ExprNode>();
if (ctxArgs != null && ctxArgs.libFunctionArgItem() != null)
{
args = ASTExprHelper.ExprCollectSubNodes(ctxArgs, 0, astExprNodeMap);
}
var numArgsPositional = ExprAggregateNodeUtil.CountPositionalArgs(args);
var isDistinct = ctxArgs != null && ctxArgs.DISTINCT() != null;
if (numArgsPositional > 1 && isDistinct && !filtered)
{
throw ASTWalkException.From(
"The distinct keyword is not valid in per-row min and max " +
"functions with multiple sub-expressions");
}
ExprNode minMaxNode;
if (!isDistinct && numArgsPositional > 1 && !filtered)
{
// use the row function
minMaxNode = new ExprMinMaxRowNode(minMaxTypeEnum);
}
else
{
// use the aggregation function
minMaxNode = new ExprMinMaxAggrNode(isDistinct, minMaxTypeEnum, filtered, false);
}
minMaxNode.AddChildNodes(args);
astExprNodeMap.Put(ctxArgs, minMaxNode);
}
private static ExprNode HandleMinMaxNode(
string chainFirstLowerCase,
Chainable spec)
{
MinMaxTypeEnum minMaxTypeEnum;
var filtered = chainFirstLowerCase.StartsWith("f");
if (chainFirstLowerCase.Equals("min") || chainFirstLowerCase.Equals("fmin"))
{
minMaxTypeEnum = MinMaxTypeEnum.MIN;
}
else if (chainFirstLowerCase.Equals("max") || chainFirstLowerCase.Equals("fmax"))
{
minMaxTypeEnum = MinMaxTypeEnum.MAX;
}
else
{
throw new ValidationException("Uncountered unrecognized min or max node '" + spec.GetRootNameOrEmptyString() + "'");
}
var args = spec.GetParametersOrEmpty();
var distinct = spec.IsDistinct;
var numArgsPositional = ExprAggregateNodeUtil.CountPositionalArgs(args);
if (numArgsPositional > 1 && spec.IsDistinct && !filtered)
{
throw new ValidationException(
"The distinct keyword is not valid in per-row min and max " +
"functions with multiple sub-expressions");
}
ExprNode minMaxNode;
if (!distinct && numArgsPositional > 1 && !filtered)
{
// use the row function
minMaxNode = new ExprMinMaxRowNode(minMaxTypeEnum);
}
else
{
// use the aggregation function
minMaxNode = new ExprMinMaxAggrNode(distinct, minMaxTypeEnum, filtered, false);
}
minMaxNode.AddChildNodes(args);
return(minMaxNode);
}