public override bool IsComparable(DataType type)
{
return(type is NumericType || type is BooleanType);
}
protected override object CastObjectTo(object value, DataType destType)
{
var n = (Number)value;
var sqlType = destType.SqlType;
switch (sqlType)
{
case (SqlType.Bit):
case (SqlType.Boolean):
return(n.ToBoolean());
case (SqlType.TinyInt):
case (SqlType.SmallInt):
case (SqlType.Integer):
return((Number)n.ToInt32());
case (SqlType.BigInt):
return((Number)n.ToInt64());
case (SqlType.Float):
case (SqlType.Real):
case (SqlType.Double):
double d = n.ToDouble();
NumberState state = NumberState.None;
if (Double.IsNaN(d))
{
state = NumberState.NotANumber;
}
else if (Double.IsPositiveInfinity(d))
{
state = NumberState.PositiveInfinity;
}
else if (Double.IsNegativeInfinity(d))
{
state = NumberState.NegativeInfinity;
}
return(new Number(state, new BigDecimal(d)));
case (SqlType.Numeric):
// fall through
case (SqlType.Decimal):
return(Number.Parse(n.ToString()));
case (SqlType.Char):
return(new StringObject(CastUtil.PaddedString(n.ToString(), ((StringType)destType).MaxSize)));
case (SqlType.VarChar):
case (SqlType.LongVarChar):
return(new StringObject(n.ToString()));
case (SqlType.Date):
case (SqlType.Time):
case (SqlType.TimeStamp):
return(ToDate(n.ToInt64()));
case (SqlType.Blob):
// fall through
case (SqlType.Binary):
// fall through
case (SqlType.VarBinary):
// fall through
case (SqlType.LongVarBinary):
return(new BinaryObject(n.ToByteArray()));
case (SqlType.Null):
return(null);
default:
throw new InvalidCastException();
}
}
public override DataType Wider(DataType otherType)
{
SqlType t1SqlType = SqlType;
SqlType t2SqlType = otherType.SqlType;
if (t1SqlType == SqlType.Decimal)
{
return(this);
}
if (t2SqlType == SqlType.Decimal)
{
return(otherType);
}
if (t1SqlType == SqlType.Numeric)
{
return(this);
}
if (t2SqlType == SqlType.Numeric)
{
return(otherType);
}
if (t1SqlType == SqlType.Bit)
{
return(otherType); // It can't be any smaller than a Bit
}
if (t2SqlType == SqlType.Bit)
{
return(this);
}
int t1IntSize = GetIntSize(t1SqlType);
int t2IntSize = GetIntSize(t2SqlType);
if (t1IntSize > 0 && t2IntSize > 0)
{
// Both are int types, use the largest size
return((t1IntSize > t2IntSize) ? this : otherType);
}
int t1FloatSize = GetFloatSize(t1SqlType);
int t2FloatSize = GetFloatSize(t2SqlType);
if (t1FloatSize > 0 && t2FloatSize > 0)
{
// Both are floating types, use the largest size
return((t1FloatSize > t2FloatSize) ? this : otherType);
}
if (t1FloatSize > t2IntSize)
{
return(this);
}
if (t2FloatSize > t1IntSize)
{
return(otherType);
}
if (t1IntSize >= t2FloatSize || t2IntSize >= t1FloatSize)
{
// Must be a long (8 bytes) and a real (4 bytes), widen to a double
return(new NumericType(SqlType.Double, 8, 0));
}
// NOTREACHED - can't get here, the last three if statements cover
// all possibilities.
throw new ApplicationException("Widest type error.");
}
