criteria progress

include/matador/sql/dialect.hpp

@@ -152,6 +152,8 @@ public:
   [[nodiscard]] const std::string& in() const;
   [[nodiscard]] const std::string& insert() const;
   [[nodiscard]] const std::string& into() const;
+  [[nodiscard]] const std::string& is_null() const;
+  [[nodiscard]] const std::string& is_not_null() const;
   [[nodiscard]] const std::string& join() const;
   [[nodiscard]] const std::string& like() const;
   [[nodiscard]] const std::string& limit() const;
@@ -218,6 +220,8 @@ private:
     {dialect_token::In,          "IN"},
     {dialect_token::Insert,      "INSERT"},
     {dialect_token::Into,        "INTO"},
+    {dialect_token::IsNull,      "IS NULL"},
+    {dialect_token::IsNotNull,   "IS NOT NULL"},
     {dialect_token::Join,        "LEFT JOIN"},
     {dialect_token::Like,        "LIKE"},
     {dialect_token::Limit,       "LIMIT"},

include/matador/sql/dialect_token.hpp

@@ -35,6 +35,8 @@ enum class dialect_token : uint8_t {
   In,
   Insert,
   Into,
+  IsNull,
+  IsNotNull,
   Join,
   Like,
   Limit,