sql select join progress

include/matador/sql/dialect.hpp

@@ -88,6 +88,7 @@ public:
  * @return The prepared string
  */
   [[nodiscard]] std::string prepare_identifier(const column &col) const;
+  [[nodiscard]] std::string prepare_identifier_string(const std::string &col) const;
 
   /**
    * Prepare string literal

include/matador/utils/string.hpp

@@ -15,10 +15,9 @@ namespace matador::utils {
  *
  * @param str The string to split.
  * @param delim The delimiter character.
- * @param values The result vector.
- * @return The size of the vector.
+ * @return The the vector with split strings.
  */
-size_t split(const std::string &str, char delim, std::vector<std::string> &values);
+std::vector<std::string> split(const std::string &str, char delim);
 
 /**
  * Replaces all occurrences of string from in given string