Use string-join instead of mapconcat

emacsql-compiler.el

@@ -12,6 +12,8 @@
 
 (require 'cl-lib)
 
+(eval-when-compile (require 'subr-x))
+
 ;;; Error symbols
 
 (defmacro emacsql-deferror (symbol parents message)
@@ -507,8 +509,7 @@ Only use within `emacsql-with-params'!"
                  (emacsql-escape-scalar item))))
              into parts
              do (setq last item)
-             finally (cl-return
-                      (mapconcat #'identity parts " ")))))
+             finally (cl-return (string-join parts " ")))))
 
 (defun emacsql-prepare (sql)
   "Expand SQL (string or sexp) into a prepared statement."

emacsql-sqlite.el

@@ -19,6 +19,8 @@
 
 ;;; Code:
 
+(eval-when-compile (require 'subr-x))
+
 (require 'emacsql)
 (require 'emacsql-sqlite-common)
 
@@ -153,7 +155,7 @@ If called with non-nil ERROR, signal an error on failure."
       (let ((log (get-buffer-create byte-compile-log-buffer)))
         (with-current-buffer log
           (let ((inhibit-read-only t))
-            (insert (mapconcat #'identity (cons cc arguments) " ") "\n")
+            (insert (string-join (cons cc arguments) " ") "\n")
             (let ((pos (point))
                   (ret (apply #'call-process cc nil (if async 0 t) t
                               arguments)))