Noting differences between Datomic and Datomish.

Differences-from-Datomic.md

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+## fulltext
+
+The `fulltext` function in Datomish supports sets of attributes or the special keyword `:any`.
+
+To do a fulltext search that matches page titles or excerpts:
+
+```
+[(fulltext $ #{:page/title :page/excerpt} "something") [[?page]]]
+```
+
+To match any attribute at all:
+```
+[(fulltext $ :any "something") [[?entity]]]
+```
+
+## Query inputs, ordering, and limits
+
+`<q` supports binding values, specifying ordering conditions, and limiting the number of returned results.
+
+Aggregates can be used as an ordering clause: for an aggregate expression like `(max ?date)`, the ordering column is `_max_date`. In ClojureScript this is a keyword (`:_max_date`); in JS it's a string.
+
+**ClojureScript**:
+
+```
+(d/<q
+  db
+  '[:find ?page ?url ?title ?excerpt
+    :in $ ?time
+    :where
+    [?save :save/page ?page]
+    [?save :save/savedAt ?instant]
+    [(> ?instant ?time)]
+    [?page :page/url ?url]
+    [(get-else $ ?save :save/title "") ?title]
+    [(get-else $ ?save :save/excerpt "") ?excerpt]]
+  {:limit limit
+   :inputs {:time 1234567890}
+   :order-by [[:instant :desc]]})
+```
+
+**JS**:
+
+```
+await db.q(
+    `[:find ?url (max ?date)
+      :in $
+      :where
+      [?page :page/url ?url]
+      [?page :page/visitedAt ?date]]`,
+    {"limit": 2, "order-by": [["_max_date", "desc"]]});
+```