plan for some revamp

PLAN.md

@@ -34,8 +34,69 @@ let z = select {} : Vertex
 ```
 
 ```
-let vs with
-[a:V]
-[v:X]
-[p:=z]
-```
+ from(e:Employee)
+.where(e.id > 10)
+.select(x: {id: e.id, name: e.first_name ++ e.last_name})
+.skip(10)
+.take(20);
+```
+
+```
+ from(e:Employee-[hj:HasJob]->j:Job)
+.where(e.id == 20)
+.select({..j});
+
+query DoThis(x:Int, y:Any) {
+    return select(-[v:V]->)
+          .where(v.id >= x, v.data == y);
+}
+```
+
+```
+query DoThat(r:Rel(*id: Int)) {
+    ...
+}
+```
+
+```
+global query XXX() {
+    ...
+}
+```
+
+# Operations on relations
+
+Operations
+
+* `from(...rels)`, can use chain notation
+* `join(left, right, ...conds)`
+* `left_join(left, right, ...conds)`, similarly for `right_join`, `outer_join`)
+* `intersect(...rels)`, similarly for `union`
+* `diff(left, right)`, similarly for `sym_diff`
+* `select(rel, binding: {..})`
+* `where(rel, ..conds)`
+* `take(rel, n)`
+* `skip(rel, n)`
+* `sort(rel, expr1, expr2: sort_dir)`
+* `group(rel, binding: {*key1: expr1, val1: expr2})`
+* `window(rel, ...)`, maybe various flavours
+* `freeze(rel)`, disables structural optimization
+* `materialize(rel)`, forces materialization
+* `merge(...rels)`, concat data cols, key cols must be the same, if names clash last wins. Same for `left_merge`, `right_merge`, `outer_merge`
+* `walk(pattern, ...conds, ...bindings)`
+* `walk_repeat(pattern, ...conds, ...bindings)` every element contains additional `_iter` and `_visited` fields
+* `values(data, ?Table)`
+* `nested_values(data, ?Table).extract(Table)`
+* `as(rel, Table)`
+* `as_keyed_by(rel, Table)`
+* `update(rel, Table)`
+* `delete(rel, Table)`
+* `insert(rel, Table)`
+* `upsert(rel, Table)`
+
+Helpers
+
+* `print(rel)`
+* `print_schema(rel)`
+* `print_plan(rel)`
+* `print_optimized(rel)`