Hash join: Difference between revisions

Line 965:

(defun make-multi-map (rows)

(let ((~~map1~~ ~~'()~~))

(let ((multi-map nil))

~~(defun~~ ~~place_line~~ (row)

(cl-loop for row in rows do

(let ((name (car row)))

(let* ((name (car row))

(if (assoc name ~~map1~~)

(name-list (assoc name multi-map)))

(~~let~~ ~~((rc~~-list ~~(assoc name map1)))~~

(if name-list

(~~setcdr~~ ~~(nthcdr (1- (length rc~~-list~~)) rc-list)~~ (list row)) )

(nconc name-list (list row))

(progn

(add-to-list '~~map1~~ (list name row) 't)) ) )

(add-to-list 'multi-map (list name row) 't) ) ) ) )

(mapcar 'place_line rows)

~~map1~~))

multi-map) )

(defun join-tables (table1 table2)

(let ((multi-map (make-multi-map table2))

(result-table '()))

(cl-loop

(cl-loop for row in table1 do

(let ((multi-rc (assoc (cdr row) multi-map)))

for row in table1 do

(~~progn~~

(when multi-rc

~~(let ((~~multi-rc ~~(assoc~~ (cdr ~~row)~~ multi-~~map))~~)

(cl-loop for multi-line in (cdr multi-rc) do

(add-to-list 'result-table

(when multi-rc

(~~cl-loop~~ ~~for~~ multi-line in (cdr multi-rc) do

(list (car row) (cdr row) (car multi-line) (cdr multi-line))

~~(add-to-list~~ ~~'result-table (list row~~ ~~multi-line)~~ 't))))))

't)))))

result-table))

(let ((table1 '((27 . "Jonah")

Line 998:

Line 997:

("Alan" . "Zombies")

("Glory" . "Buffy"))))

(join-tables table1 table2))

(message "%s" (join-tables table1 table2)) )

</syntaxhighlight>