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I see everywhere constructions like: int? myVar = null; string test = myVar.HasValue ? myVar.Value.ToString() : string.Empty;
I want to generate this SQL statement in LINQ: select * from Foo where Value in ( 1, 2, 3 ) The tricky bit seems to be that Value is a column that allows nulls.
Is there any difference between the 2 methods bel开发者_如何学运维ow for calculating c ... specifically boxing/unboxing issues?
I need to add a NOT NULL column to an existing (populated) table that will be a foreign key to another table. This brings about two problems:
I have a problem with a query using hibernate. The entity class EntityClass has an embedded property embedded of type EmbeddedClass开发者_如何转开发 and this property has a nullable property optional.
I\'m attempting to map values of properties (via reflection) between different objects. This appe开发者_JAVA百科ars to be failing oddly on nullable value types. The following code:
I have a few places where I need to compare 2 (nullable) values, to see if they\'re t开发者_开发知识库he same.
trait NotNull {} I\'ve been trying to see how this trai开发者_如何学编程t can guarantee that something is not null and I can\'t figure it out:
I have: Class Foo { String name; String value; Foo parent; //Foo.parent is OneToOne and nullable } I have the following HQL:
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