private string Base(Expression exp)
{
var cached = (CachedExpression)exp;
if (cached.Sql != null)
{
return(cached.Sql);
}
cached.Sql = exp switch
{
UnionExpression e => Union(e),
SelectExpression e => Select(e),
WhereExpression e => Where(e),
MaxExpression e => Max(e),
MinExpression e => Min(e),
SumExpression e => Sum(e),
CountExpression e => Count(e),
TakeExpression e => Take(e),
SkipExpression e => Skip(e),
FirstExpression e => First(e),
DistinctExpression e => Distinct(e),
OrderByExpression e => OrderBy(e),
OrderByDescendingExpression e => OrderByDescending(e),
_ => throw new InvalidEnumArgumentException()
};
return(cached.Sql);
}
private string OrderByDescending(OrderByDescendingExpression exp) => $"SELECT * FROM ({Serialize(exp.Sub)}) AS this ORDER BY {Secondary.Serialize(exp.KeySelector.Body)} DESC OFFSET 0 ROWS";
