diff --git a/lib/datalog/magic.sx b/lib/datalog/magic.sx index 7c8983a1..7ea1b548 100644 --- a/lib/datalog/magic.sx +++ b/lib/datalog/magic.sx @@ -341,3 +341,63 @@ query-rel query-adornment query-args)})))) + +;; ── Top-level magic-sets driver ───────────────────────────────── +;; +;; (dl-magic-query db query-goal) — run `query-goal` under magic-sets +;; evaluation. Builds a fresh internal db with: +;; - the caller's EDB facts (relations not headed by any rule), +;; - the magic seed fact, and +;; - the rewritten rules. +;; Saturates and queries, returning the substitution list. The +;; caller's db is untouched. +;; +;; Useful primarily as a perf alternative for queries that only +;; need a small slice of a recursive relation. Equivalent to +;; dl-query for any single fully-stratifiable program. + +(define + dl-magic-rule-heads + (fn + (rules) + (let ((seen (list))) + (do + (for-each + (fn + (r) + (let ((h (dl-rel-name (get r :head)))) + (when + (and (not (nil? h)) (not (dl-member-string? h seen))) + (append! seen h)))) + rules) + seen)))) + +(define + dl-magic-query + (fn + (db query-goal) + (let + ((query-rel (dl-rel-name query-goal)) + (query-adn (dl-adorn-goal query-goal))) + (let + ((query-args (dl-bound-args query-goal query-adn)) + (rules (dl-rules db))) + (let + ((rewritten (dl-magic-rewrite rules query-rel query-adn query-args)) + (mdb (dl-make-db)) + (rule-heads (dl-magic-rule-heads rules))) + (do + ;; Copy EDB facts (relations not headed by any caller rule). + (for-each + (fn + (rel) + (when + (not (dl-member-string? rel rule-heads)) + (for-each + (fn (t) (dl-add-fact! mdb t)) + (dl-rel-tuples db rel)))) + (keys (get db :facts))) + ;; Seed + rewritten rules. + (dl-add-fact! mdb (get rewritten :seed)) + (for-each (fn (r) (dl-add-rule! mdb r)) (get rewritten :rules)) + (dl-query mdb query-goal))))))) diff --git a/lib/datalog/scoreboard.json b/lib/datalog/scoreboard.json index 481f48f9..b44085fa 100644 --- a/lib/datalog/scoreboard.json +++ b/lib/datalog/scoreboard.json @@ -1,8 +1,8 @@ { "lang": "datalog", - "total_passed": 202, + "total_passed": 204, "total_failed": 0, - "total": 202, + "total": 204, "suites": [ {"name":"tokenize","passed":26,"failed":0,"total":26}, {"name":"parse","passed":18,"failed":0,"total":18}, @@ -13,8 +13,8 @@ {"name":"negation","passed":10,"failed":0,"total":10}, {"name":"aggregates","passed":18,"failed":0,"total":18}, {"name":"api","passed":14,"failed":0,"total":14}, - {"name":"magic","passed":18,"failed":0,"total":18}, + {"name":"magic","passed":20,"failed":0,"total":20}, {"name":"demo","passed":18,"failed":0,"total":18} ], - "generated": "2026-05-08T09:58:16+00:00" + "generated": "2026-05-08T10:00:29+00:00" } diff --git a/lib/datalog/scoreboard.md b/lib/datalog/scoreboard.md index def16294..27c9bab8 100644 --- a/lib/datalog/scoreboard.md +++ b/lib/datalog/scoreboard.md @@ -1,6 +1,6 @@ # datalog scoreboard -**202 / 202 passing** (0 failure(s)). +**204 / 204 passing** (0 failure(s)). | Suite | Passed | Total | Status | |-------|--------|-------|--------| @@ -13,5 +13,5 @@ | negation | 10 | 10 | ok | | aggregates | 18 | 18 | ok | | api | 14 | 14 | ok | -| magic | 18 | 18 | ok | +| magic | 20 | 20 | ok | | demo | 18 | 18 | ok | diff --git a/lib/datalog/tests/magic.sx b/lib/datalog/tests/magic.sx index 78ad1d27..568409ce 100644 --- a/lib/datalog/tests/magic.sx +++ b/lib/datalog/tests/magic.sx @@ -196,6 +196,34 @@ (len (dl-relation db "ancestor"))))) 6) + ;; dl-magic-query: end-to-end driver, doesn't mutate caller's db. + (dl-mt-test! "magic-query equivalent to dl-query" + (let + ((db (dl-program + "parent(a, b). parent(b, c). parent(c, d). + ancestor(X, Y) :- parent(X, Y). + ancestor(X, Z) :- parent(X, Y), ancestor(Y, Z)."))) + (let + ((semi (dl-query db (list (quote ancestor) (quote a) (quote X)))) + (magic (dl-magic-query + db (list (quote ancestor) (quote a) (quote X))))) + (= (len semi) (len magic)))) + true) + + ;; magic-query doesn't mutate caller db. + (dl-mt-test! "magic-query preserves caller db" + (let + ((db (dl-program + "parent(a, b). parent(b, c). + ancestor(X, Y) :- parent(X, Y). + ancestor(X, Z) :- parent(X, Y), ancestor(Y, Z)."))) + (let + ((rules-before (len (dl-rules db)))) + (do + (dl-magic-query db (list (quote ancestor) (quote a) (quote X))) + (= rules-before (len (dl-rules db)))))) + true) + (dl-mt-test! "magic-rewritten finds same answers" (let ((rules diff --git a/plans/datalog-on-sx.md b/plans/datalog-on-sx.md index 4b9d41a8..f68428d9 100644 --- a/plans/datalog-on-sx.md +++ b/plans/datalog-on-sx.md @@ -174,11 +174,15 @@ large graphs. - [x] Equivalence test: rewritten ancestor program over the same EDB derives the same number of `ancestor` tuples and returns the same query answers as the unrewritten program (chain-3 case). +- [x] `dl-magic-query db query-goal` — top-level driver. Builds a + fresh internal db with the caller's EDB facts, the magic seed, + and the rewritten rules; saturates and queries. Caller's db is + untouched. Equivalent to `dl-query` for fully-stratifiable + programs (sole motivation is a perf alternative on goal-shaped + queries against large recursive relations). - [ ] Perf test: 10k-node reachability with magic vs semi-naive. - Pending — would need a `dl-saturate-magic!` driver that builds - a temporary db from rewrite output. The rewriter itself is in - place; benchmarking against semi-naive on large graphs is left - to a future iteration. + Left to a future iteration — would need a benchmarking harness + for large graphs and the conformance budget can't afford it. ### Phase 7 — stratified negation - [x] Dependency graph: `dl-build-dep-graph db` returns `{head -> ({:rel @@ -299,6 +303,14 @@ large graphs. _Newest first._ +- 2026-05-08 — Phase 6 driver: `dl-magic-query db query-goal`. + Builds a fresh internal db from the caller's EDB + magic seed + + rewritten rules, saturates, queries, returns substitutions — + caller's db is untouched. Equivalent to `dl-query` for any + fully-stratifiable program; sole motivation is a perf alternative + on goal-shaped queries against large recursive relations. + 2 new tests cover equivalence and non-mutation. + - 2026-05-08 — Phase 6 magic-sets rewriter. `dl-magic-rewrite rules query-rel adn args` returns `{:rules :seed }`. Worklist over `(rel, adn)` pairs starts from the query, gates each