UpdateNonDefaults is ignoring boolean parameters set to false

Question

I'm trying to update a record in my SQL server 2012 Express DB using UpdateNonDefaults. Boolean fields which are set to false are getting ignored as can be seen from the SQL statement.

How can I set DB value to false for boolean fields using UpdateNonDefaults?

Thanks in advance..

Answer 1

Please post your code, or we can't tell what is wrong...

Try:

[Default(typeof(bool?), null)] 
public bool? Foo {get;set;} 

Or try :

[Default(typeof(int?), null)] 
public int? Foo {get; set;} 

See if it works?

Answer 2

As a work-around, I have changed my "bool" data types to "string" and am using bool.FalseString and bool.TrueString to set my values. Not nice...

Answer 3

This is not the ideal solution but I used anonymous type as mentioned here to update the null-able boolean field and it worked.

One way to limit the fields which gets updated is to use an Anonymous Type:

db.Update<Person>(new { FirstName = "JJ" }, p => p.LastName == "Hendrix");

Does anyone know why UpdateNonDefaults does not update boolean values to false?

Answer 4

While you call the UpdateNonDefaults method, it generates sql via the method ToUpdateStatement in SqlExpression.cs

public virtual string ToUpdateStatement(T item, bool excludeDefaults = false)
{
    var setFields = new StringBuilder();

    foreach (var fieldDef in modelDef.FieldDefinitions)
    {
        if (fieldDef.ShouldSkipUpdate()) continue;
        if (fieldDef.IsRowVersion) continue;
        if (updateFields.Count > 0 && !updateFields.Contains(fieldDef.Name)) continue; // added

        var value = fieldDef.GetValue(item);
        if (excludeDefaults && (value == null || value.Equals(value.GetType().GetDefaultValue()))) continue; //GetDefaultValue?

        fieldDef.GetQuotedValue(item, DialectProvider);

        if (setFields.Length > 0)
            setFields.Append(", ");

        setFields
            .Append(DialectProvider.GetQuotedColumnName(fieldDef.FieldName))
            .Append("=")
            .Append(DialectProvider.GetQuotedValue(value, fieldDef.FieldType));
    }

    return string.Format("UPDATE {0} SET {1} {2}",
        DialectProvider.GetQuotedTableName(modelDef), setFields, WhereExpression);
}

Please note the line:

if (excludeDefaults && (value == null || value.Equals(value.GetType().GetDefaultValue()))) continue; //GetDefaultValue?

When you update a nullable boolean value from true to false, here the value is fasle, and value.GetType() is actually typeof(bool) while not typeof(bool?), so value.GetType().GetDefaultValue() is always false. Then, this column is ignored...