Improve column formatting.

Have a pretty-print option where we try to be nice for the reader, and
don't use it in the CAST debug messages. Also allow working with the
real maximum length of column names rather than hardcoding 22 cols...

src/pgsql/schema.lisp

@@ -116,10 +116,15 @@
     (format s "CREATE TABLE~:[~; IF NOT EXISTS~] ~a ~%(~%"
             if-not-exists
             (format-table-name table))
-    (loop
-       :for (col . last?) :on (table-column-list table)
-       :for pg-coldef := (format-column col)
-       :do (format s "  ~a~:[~;,~]~%" pg-coldef last?))
+    (let ((max (reduce #'max
+                       (mapcar #'length
+                               (mapcar #'column-name (table-column-list table))))))
+     (loop
+        :for (col . last?) :on (table-column-list table)
+        :for pg-coldef := (format-column col
+                                         :pretty-print t
+                                         :max-column-name-length max )
+        :do (format s "  ~a~:[~;,~]~%" pg-coldef last?)))
     (format s ");~%")))
 
 (defun drop-table-if-exists-sql (table)

src/utils/pg-format-column.lisp

@@ -29,11 +29,18 @@
                         nil)))
 	 (format nil "'~a'" default)))))
 
-(defmethod format-column ((column column))
+(defgeneric format-column (column &key pretty-print)
+  (:documentation "Format COLUMN definition for CREATE TABLE purpose."))
+
+(defmethod format-column ((column column)
+                          &key
+                            pretty-print
+                            ((:max-column-name-length max)))
   "Format the PostgreSQL data type."
   (format nil
-          "~a ~22t ~a~:[~*~;~a~]~:[ not null~;~]~:[~; default ~a~]"
+          "~a~vt~a~:[~*~;~a~]~:[ not null~;~]~:[~; default ~a~]"
           (column-name column)
+          (if pretty-print (or (+ 2 max) 22) 1)
           (column-type-name column)
           (column-type-mod column)
           (column-type-mod column)