Misc fixes. Remove old sqlite tests.

Author: bordoley

SQLitePCL.pretty.Orm/TableMapping.cs

@@ -235,7 +235,10 @@ private static TableColumnMetadata CreateColumnMetadata(this PropertyInfo This)
             }
 
             // Though technically not required to be not null by SQLite, we enforce that the primary key is always not null
-            var hasNotNullConstraint = isPK || This.HasNotNullConstraint() || columnType.GetTypeInfo().IsValueType;
+            var hasNotNullConstraint = 
+                isPK || 
+                This.HasNotNullConstraint() || 
+                (columnType.GetTypeInfo().IsValueType && !columnType.IsNullable());
 
             return new TableColumnMetadata(columnType.GetSQLiteType().ToSQLDeclaredType(), collation, hasNotNullConstraint, isPK, isAutoInc);
         }

SQLitePCL.pretty.Orm/TableQuery.cs

@@ -205,25 +205,25 @@ private TableQuery<T> AddOrderBy<TValue>(Expression<Func<T, TValue>> orderExpr,
 
         public TableQuery<T> OrderBy<TValue>(Expression<Func<T, TValue>> orderExpr)
         {
-            // FIXME: Throw an exception if order by is not empty?
+            if (this._orderBy.Count != 0) { throw new NotSupportedException("OrderBy can only be called once"); };
             return AddOrderBy(orderExpr, true);
         }
 
         public TableQuery<T> OrderByDescending<TValue>(Expression<Func<T, TValue>> orderExpr)
         {
-            // FIXME: Throw an exception if order by is not empty?
+            if (this._orderBy.Count != 0) { throw new NotSupportedException("OrderBy can only be called once"); };
             return AddOrderBy(orderExpr, false);
         }
 
         public TableQuery<T> ThenBy<TValue>(Expression<Func<T, TValue>> orderExpr)
         {
-            // FIXME: Throw an exception if order by is empty?
+            if (this._orderBy.Count == 0) { throw new NotSupportedException("Must call OrderBy before ThenBy"); };
             return AddOrderBy(orderExpr, true);
         }
 
         public TableQuery<T> ThenByDescending<TValue>(Expression<Func<T, TValue>> orderExpr)
         {
-            // FIXME: Throw an exception if order by is empty?
+            if (this._orderBy.Count == 0) { throw new NotSupportedException("Must call OrderBy before ThenBy"); };
             return AddOrderBy(orderExpr, false);
         }