From cff49b6df5702087ad9c9f10a768c8626f268b63 Mon Sep 17 00:00:00 2001
From: Richard Newman <rnewman@twinql.com>
Date: Wed, 17 Aug 2016 11:21:50 -0700
Subject: [PATCH] Initialize the sqlite connection with WAL and foreign keys.

This somewhat improves performance, which is nice.
---
 src/datomish/db_factory.cljc | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/src/datomish/db_factory.cljc b/src/datomish/db_factory.cljc
index a8850d92..589a5484 100644
--- a/src/datomish/db_factory.cljc
+++ b/src/datomish/db_factory.cljc
@@ -67,9 +67,20 @@
                                 [(<-SQLite (:attr row)) (<-SQLite (:value row))]) rows))]))
         (into {})))))
 
+(defn <initialize-connection [sqlite-connection]
+  (go-pair
+    ;; Some of these return values when set, and some don't, hence the craziness here.
+    (<? (s/execute! sqlite-connection ["PRAGMA page_size=32768"]))
+    (<? (s/all-rows sqlite-connection ["PRAGMA journal_mode=wal"]))
+    (<? (s/all-rows sqlite-connection ["PRAGMA wal_autocheckpoint=32"]))
+    (<? (s/all-rows sqlite-connection ["PRAGMA journal_size_limit=3145728"]))
+    (<? (s/execute! sqlite-connection ["PRAGMA foreign_keys=ON"]))))
+
 (defn <db-with-sqlite-connection
   [sqlite-connection]
   (go-pair
+    (<? (<initialize-connection sqlite-connection))
+
     (when-not (= sqlite-schema/current-version (<? (sqlite-schema/<ensure-current-version sqlite-connection)))
       (raise "Could not ensure current SQLite schema version."))