Meh. Depends who your client is. WidgetCo needs a CRUD app? Sure, their "serial #" field ought to be TEXT; their definition of "number" probably already includes "0001234-45-X" and is going to change in a month.
EmbeddedNetworkApplianceInc needs a database to manage their mission-critical data path? That IPv4 mask length field is going to be INTEGER NOT NULL CHECK (masklen BETWEEN 0 AND 32) and they can ALTER TABLE when they need to support IPv6 and the rest of their software is ready to support a masklen of 128 without crashing. There's no reason to let extraneous half-baked crap get into that field.
EmbeddedNetworkApplianceInc needs a database to manage their mission-critical data path? That IPv4 mask length field is going to be INTEGER NOT NULL CHECK (masklen BETWEEN 0 AND 32) and they can ALTER TABLE when they need to support IPv6 and the rest of their software is ready to support a masklen of 128 without crashing. There's no reason to let extraneous half-baked crap get into that field.