c# - How to solve the cast to value type 'System.Decimal' failure error -

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the cast value type 'system.decimal' failed because materialized value null. either result type's generic parameter or query must use nullable type.

public class bar {     [key]     public int barid { get; set; }     public int quantity { get; set; }     public decimal? unittotal{get { return quantity * (pricelist == null ? 0 : pricelist.price); }}     public decimal? dailytotal { get; set; }     public int pricelistid { get; set; }     public virtual pricelist pricelist { get; set; } }  bar.dailytotal = db.bars.sum(h => h.quantity * h.pricelist.price);

edit: sounds 1 of mapped types resolving null. such quantity or price fields.

check schema/mapping make sure if nullable mapped nullable type.


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