private bool Test(Expression e)
{
if (e == null)
{
return(true);
}
return(e.Test());
}
/// <summary>
/// Gets the expression resulting value.
/// </summary>
/// <returns></returns>
public object GetValue()
{
switch (_type)
{
case ExpressionType.Value:
return(_data);
case ExpressionType.DatabaseColumn:
try
{
return(tFilter.oCurrentData[iColumn]);
}
catch
{
throw Trace.Error(Trace.COLUMN_NOT_FOUND, sColumn);
}
case ExpressionType.Function:
return(fFunction.GetValue());
case ExpressionType.Query:
return(sSelect.GetValue(_columnType));
case ExpressionType.Negate:
return(Column.Negate(eArg.GetValue(_columnType), _columnType));
case ExpressionType.Count:
// count(*): sum(1); count(col): sum(col<>null)
if (eArg.Type == ExpressionType.Asterix || eArg.GetValue() != null)
{
return(1);
}
return(0);
case ExpressionType.Maximum:
case ExpressionType.Minimum:
case ExpressionType.Sum:
case ExpressionType.Average:
return(eArg.GetValue());
case ExpressionType.Exists:
return(Test());
case ExpressionType.Convert:
return(eArg.GetValue(_columnType));
case ExpressionType.CaseWhen:
if (eArg.Test())
{
return(eArg2.eArg.GetValue());
}
else
{
return(eArg2.eArg2.GetValue());
}
case ExpressionType.Variable:
return(eArg.GetValue());
}
// todo: simplify this
object a = null, b = null;
if (eArg != null)
{
a = eArg.GetValue(_columnType);
}
if (eArg2 != null)
{
b = eArg2.GetValue(_columnType);
}
switch (_type)
{
case ExpressionType.Add:
return(Column.Add(a, b, _columnType));
case ExpressionType.Subtract:
return(Column.Subtract(a, b, _columnType));
case ExpressionType.Multiply:
return(Column.Multiply(a, b, _columnType));
case ExpressionType.Divide:
return(Column.Divide(a, b, _columnType));
case ExpressionType.Concat:
return(Column.Concat(a, b, _columnType));
case ExpressionType.IfNull:
return(a == null ? b : a);
case ExpressionType.Equal:
if (eArg.Type == ExpressionType.Variable)
{
Trace.Check(eArg2 != null, Trace.GENERAL_ERROR);
return(eArg2.GetValue(eArg._columnType));
}
else
{
return(Test());
}
default:
// must be comparisation
// todo: make sure it is
return(Test());
}
}
private bool Test(Expression e)
{
if (e == null)
{
return true;
}
return e.Test();
}
// [email protected] end changes from 1.50 // [email protected] begin changes from 1.50 public Result GetResult(int start, int cnt, Channel cChannel) { int maxrows = start + cnt; //<-new, cut definitly // [email protected] begin changes from 1.50 Resolve(); CheckResolved(); if (sUnion != null && sUnion.iResultLen != iResultLen) { throw Trace.Error(Trace.COLUMN_COUNT_DOES_NOT_MATCH); } int len = eColumn.Length; Result r = new Result(len); bool aggregated = false; bool grouped = false; for (int i = 0; i < len; i++) { Expression e = eColumn[i]; r.Type[i] = e.ColumnType; if (e.IsAggregate) { aggregated = true; } } object[] agg = null; if (aggregated) { agg = new object[len]; } if (iGroupLen > 0) { // has been set in Parser grouped = true; } bool simple_maxrows = false; if (maxrows != 0 && grouped == false && sUnion == null && iOrderLen == 0) { simple_maxrows = true; } int count = 0; int filter = tFilter.Length; bool[] first = new bool[filter]; int level = 0; while (level >= 0) { bool found = false; if (filter > 0) { TableFilter t = tFilter[level]; if (!first[level]) { found = t.FindFirst(); first[level] = found; } else { found = t.Next(); first[level] = found; } } if (!found) { level--; if (!OnlyVars) { continue; } } if (level < filter - 1) { level++; continue; } if (eCondition == null || eCondition.Test()) { object[] row = new object[len]; for (int i = 0; i < len; i++) { row[i] = eColumn[i].GetValue(); if (cChannel != null && eColumn[i].IsVarAssign) { cChannel.SetDeclareValue(eColumn[i].Arg.ColumnName, row[i]); } } count++; if (aggregated && !grouped) { UpdateAggregateRow(agg, row, len); } else { r.Add(row); if (simple_maxrows && count >= maxrows) { break; } } } } if (aggregated && !grouped) { AddAggregateRow(r, agg, len, count); } else if (grouped) { int[] order = new int[iGroupLen]; int[] way = new int[iGroupLen]; for (int i = iResultLen, j = 0; j < iGroupLen; i++, j++) { order[j] = i; way[j] = 1; } r = SortResult(r, order, way); Record n = r.Root; Result x = new Result(len); for (int i = 0; i < len; i++) { x.Type[i] = r.Type[i]; } do { object[] row = new object[len]; count = 0; bool newgroup = false; while (n != null && newgroup == false) { count++; for (int i = 0; i < iGroupLen; i++) { if (n.Next == null) { newgroup = true; } else if (Column.Compare(n.Data[i], n.Next.Data[i], r.Type[i]) != 0) { // can't use .Equals because 'null' is also one group newgroup = true; } } UpdateAggregateRow(row, n.Data, len); n = n.Next; } AddAggregateRow(x, row, len, count); } while (n != null); r = x; } if (iOrderLen != 0) { int[] order = new int[iOrderLen]; int[] way = new int[iOrderLen]; for (int i = iResultLen, j = 0; j < iOrderLen; i++, j++) { order[j] = i; way[j] = eColumn[i].IsDescending ? -1 : 1; } r = SortResult(r, order, way); } // the result maybe is bigger (due to group and order by) // but don't tell this anybody else r.SetColumnCount(iResultLen); if (bDistinct) { r = RemoveDuplicates(r); } for (int i = 0; i < iResultLen; i++) { Expression e = eColumn[i]; r.Label[i] = e.Alias; r.Table[i] = e.TableName; r.Name[i] = e.ColumnName; } if (sUnion != null) { Result x = sUnion.GetResult(0, cChannel); if (UnionType == SelectType.Union) { r.Append(x); r = RemoveDuplicates(r); } else if (UnionType == SelectType.UnionAll) { r.Append(x); } else if (UnionType == SelectType.Intersect) { r = RemoveDuplicates(r); x = RemoveDuplicates(x); r = RemoveDifferent(r, x); } else if (UnionType == SelectType.Except) { r = RemoveDuplicates(r); x = RemoveDuplicates(x); r = RemoveSecond(r, x); } } if (maxrows > 0 && !simple_maxrows) { TrimResult(r, maxrows); } // [email protected] begin changes from 1.50 if (start > 0) { //then cut the first 'start' elements TrimResultFront(r, start); } // [email protected] end changes from 1.50 return(r); }
