How do you create a yes/no boolean field in SQL server?

The equivalent is a BIT field.

In SQL you use 0 and 1 to set a bit field (just as a yes/no field in Access). In Management Studio it displays as a false/true value (at least in recent versions).

When accessing the database through ASP.NET it will expose the field as a boolean value.

The BIT datatype is generally used to store boolean values (0 for false, 1 for true).

You can use the bit column type.