markov: Update gitignore to allow db.sql to be added

Signed-off-by: Alek Ratzloff <alekratz@gmail.com>

data/markov/db.sql

@@ -0,0 +1,19 @@
+CREATE TABLE IF NOT EXISTS user (
+    id integer NOT NULL PRIMARY KEY AUTOINCREMENT,
+    nick varchar(255) NOT NULL,
+    channel varchar(255) NOT NULL,
+    reply_chance real NOT NULL
+);
+
+CREATE UNIQUE INDEX IF NOT EXISTS user_nick_channel ON user(nick, channel);
+
+CREATE TABLE IF NOT EXISTS chain (
+    id integer NOT NULL PRIMARY KEY AUTOINCREMENT,
+    user integer NOT NULL,
+    value text NOT NULL,
+    weight integer NOT NULL DEFAULT 1,
+    next text NOT NULL,
+    FOREIGN KEY(user) REFERENCES user(id)
+);
+
+CREATE UNIQUE INDEX IF NOT EXISTS chain_value_next ON chain(user, value, next);