Improve safety with enum handling

[adsharma]

We have enum class LogicalTypeID. There are a large number of switch statements in the code base which have the following anti-pattern:

• only a subset of types are handled without a default
• only a subset of types are handled with a default

One way to fix this is to remove the default clauses and compile with -Wenum-switch

Some of these were uncovered in #148