init-sql.el

(defvar my-sql-query-buffer)

(defun my-sql-query-buffer (arg)
  "Open a `sql-mode' buffer which interacts with the current SQLi buffer.
 
 Switches to an existing buffer if possible, otherwise creates a new buffer.
 
 With C-u prefix arg, always creates a new buffer."
  (interactive "P")
  (let ((sqlibuf (current-buffer)))
    (if (null (sql-buffer-live-p sqlibuf))
        (error "Buffer %s is not a working SQLi buffer" sqlibuf)
      (let ((product sql-product)
            (querybuf
             (or (and (not (consp arg)) ;; prefix arg
                      (boundp 'my-sql-query-buffer)
                      (buffer-live-p (get-buffer my-sql-query-buffer))
                      (get-buffer my-sql-query-buffer))
                 (generate-new-buffer
                  (format "*SQL ctl: %s*" (buffer-name sqlibuf))))))
        (setq-local my-sql-query-buffer querybuf)
        (pop-to-buffer querybuf '(display-buffer-reuse-window
                                  . ((reusable-frames . visible))))
        (unless (eq major-mode 'sql-mode)
          (sql-mode)
          (setq sql-product product)
          (sql-highlight-product)
          (setq sql-buffer sqlibuf)
          (run-hooks 'sql-set-sqli-hook))))))

(defun org-babel-sql-expand-vars (body vars)
  "Expand the variables held in VARS in BODY."
  (mapc
   (lambda (pair)
     (setq body
	   (replace-regexp-in-string
	    (format "$%s" (car pair))
	    (let ((val (cdr pair)))
              (if (listp val)
                  (let ((data-file (org-babel-temp-file "sql-data-")))
                    (with-temp-file data-file
                      (insert (orgtbl-to-csv val nil)))
                    data-file)
                (if (stringp val) val (format "%S" val))))
	    body)))
   vars)
  body)