nullable

Attribute value with a null reference assigned to a reference type or to a nullable value type.

The result of an arithmetic operator is always nullable, even if the operands are nonnullable and ANSI_WARNINGS or ARITHABORT is set ON.

Operator defines the default value to be returned when a nullable type is assigned to a non-nullable type.

A type parameter can be constrained to be a reference type, a non- nullable value type, and to have a default constructor .

Specifically, any type defined as Nullable(Of T) wasn't allowed to be optional.

Use nullable types to represent things that exist or do not exist depending on the circumstance.

The nullability property of arithmetic operators over floating point data type is always nullable.

Assign a value to a nullable type just as you would for an ordinary value type, for example int?

In this case, define the field to be a nullable type instead of a value type.

Though most Rails developers do not like to keep constraints in the database, you should consider things like nullable columns.

The as operator must be used with a reference type or nullable type ('int' is a non-nullable value type).

You can declare variables and properties with nullable types, and you can declare an array with elements of a nullable type.

If there is no default value and the column is not nullable, the server will return an error and an exception will be thrown.

You can also use the classes and methods of the System. Reflection namespace to generate Type objects that represent Nullable types.

In the lower right part of the section, set all key columns of the output link to non-nullable by selecting No in the nullable column.

Indicates whether the current Nullable object is equal to a specified object.

Columns in the view select list can be nullable or not nullable.

You store a value in a variable or property of a nullable type in the normal way.

Calling GetType on a Nullable type causes a boxing operation to be performed when the type is implicitly converted to Object.

True - then boxing takes place, but only the underlying type that the nullable object is based upon is boxed.

For this constraint to execute, the foreign key columns must be nullable.

If the column is NULLABLE, any number of NULLs can be inserted in that column.

Therefore you cannot use is to determine whether a variable is a Nullable type.

If the return type of the method is nullable, the distinguished null value for the type is returned.

Nullable types are a special case of generic types.

The Nullable class provides complementary support for the Nullable structure.

True clears all columns except the declared primary key, nullable columns with no default, and unique key columns.

Invokes a transform function on each element of a sequence and returns the maximum nullable Int32 value.

In this example, no one is allowed to update or insert into that column, which is also marked as unique and not nullable.

There is one major concern regarding this second strategy: in order for it to work, you must set all non-shared columns to NULLABLE.

The metadata API also provides the ability to define nullable columns, establish primary keys, and set-up relationships between tables.

ANSI_NULL defaults are always on for ALTER COLUMN; if not specified, the column is nullable.

The value returned for this column is different from the value returned for the NULLABLE column.

The expression may be a null value if the parameter is nullable.

If the target column is not nullable, the insert or update action fails and the user receives an error.

For an example of when you might use a nullable type, consider how an ordinary Boolean variable can have two values: true and false.

Nullable types are useful when working with databases and other data structures that may contain elements that contain no specific values.

Previously , the code would allow default behavior to occur when handling nullable fields .

If a column is nullable and there is no explicit default value set, NULL becomes the implicit default value of the column.

Correctly generate Update statements for nullable columns.

Returns the underlying type argument of the specified nullable type.

Initializes a new instance of the Nullable structure to the specified value.

For more examples of nullable types, including boxing behavior, see Nullable Sample.

Columns that allow null values; zero-length strings are returned if the columns are not nullable.

Sets or gets a value which indicates whether the source column is nullable.

This allows DbCommandBuilder to correctly generate Update statements for nullable columns.

Any value type may be used as the basis for a nullable type.

Value types and structures can be declared nullable.

To correctly generate update commands when dealing with nullable columns.

To correctly generate Update statements for nullable columns.

Use the following code to determine whether a Type object represents a Nullable type.

The conversion from an ordinary type to a nullable type, is implicit.

If you use a nullable VARGRAPHIC column instead , the 1021- byte index limitation is still true .

A database is one of the most important places to use nullable types.

If the return type is non-nullable, the default CLR value for the type is returned.

The nullable button should not be checked.

Operator defines a default value that is returned when a nullable type is assigned to a non-nullable type.

Any value type except Nullable can be specified.

Note how the columns have this DBCOLUMNFLAGS_ISNULLABLE for nullable columns.

Now each nullable field is checked and appropriate default values are set.

If there is no default value but the column is nullable, then NULL is inserted.

The following code example defines a method whose return value is of type Nullable of Int32.

If you use a cast, and the nullable type is currently undefined, an InvalidOperationException exception will be thrown.

Consequently, a nullable type can express a value, or that no value exists.

If the column allows null values, the return value is one of the nullable types (for example, Nullable(Of Integer)).

A SUM function that references a nullable expression.

In C# you can flag a value type as a nullable type by adding ? after the type (like int? x; ).

A Type object that describes a closed generic nullable type.

By skillful, I mean the judicious use of annotation elements such as nullable=false, which allows for only selected items to be "nullable. "

Is the underlying type of the nullable type.

The DB2Types classes also provide a means to represent DB2 database column values as individual nullable objects.

for value types , nullable types will be generated.

call the mutator for each nullable property.

A generic Nullable that represents a null XML value.

That represents the nullable type.

I recently ran MoMA on SubSonic and found only one issue - a weird use of Nullable types.

Nullable types are new to . NET 2. 0 and provide a technique for indicating whether a value type should, instead, be null.

A table should avoid nullable columns.

This operator can also be used with multiple nullable types.

Type The specified nullable type.

When using functions that can return Null, you must set the Nullable property for the attribute to True.

If nullable, it will contain the NULL value.

Nullable types are value types such as an integer or a Boolean that can be either a regular value or a null value.

You cannot create a nullable type based on a reference type.

Objects based on nullable types are only boxed if the object is non-null.

This sample demonstrates how to use nullable types.

You also need to specify that all nullable columns contain the DBCOLUMNFLAGS_ISNULLABLE value in your version of the GetColumnInfo.

Value types are also nullable, which means they can store an addition non-value state.

A nullable type can contain a value, or it can be undefined.

Two options are available: nullable types and annotations for strongly typed objects such as datasets.

A nullable type can contain a value, or it can be undefined.

Two options are available: nullable types and annotations for strongly typed objects such as datasets.

Nullable types allow a variable to contain a value that is undefined.

A column is derived from TypedElement, and it has properties, such as nullable and defaultValue.

For example, a reference type such as String is nullable, whereas a value type such as Int32 is not.

For information on using nullable types with Visual Basic, see Nullable Value Types.

Class is unable to deserialize an XML element whose data type maps to a non-nullable value type and whose

When a nullable type is boxed, the common language runtime automatically boxes the underlying value of the

For information on using nullable types with Visual Basic, see Value Types that Might Not Have a Defined Value.

Library Support for nullable types, including conversion operators and arithmetic operators

Library Support for nullable types, including conversion operators and arithmetic operators

Each instance of a nullable type has two public read-only properties

For a variable of a nullable type,

A nullable type can represent the normal range of values for its underlying value type, plus an additional null

A variable of nullable type can be set to null with the null keyword, as shown below

The default value for a nullable type variable sets

You can declare procedures with nullable types as parameters, and you can return a nullable type from a

When you declare a variable with a nullable type, its

The behavior of nullable types when boxed provides two advantages

Nullable types and null coalescing operator

Nullable types and null coalescing operator

Nullable types represent value-type variables that can be assigned the value of null

To retrieve the value of a variable of a nullable type, you should first test its

If the source column is nullable, otherwise

The most important members of a nullable type are its

For more information on nullable types, see

The Members of Nullable Types

Assign a value to a nullable type in the same way as for an ordinary value type, for example