Load schema at require time and use transactions.

lib/mbtiles.js

@@ -22,6 +22,7 @@ function hash(z, x, y) {
 // insertion, etc.)
 module.exports = MBTiles;
 MBTiles.utils = require('./utils');
+MBTiles.schema = fs.readFileSync(__dirname + '/schema.sql', 'utf8');
 
 // Provides access to an mbtiles database file.
 // - uri: A parsed URL hash, the only relevant part is `pathname`.
@@ -124,14 +125,7 @@ MBTiles.prototype._integrity = function(callback) {
 // Setup schema, indices, views for a new mbtiles database.
 // - @param {Function(err)} callback
 MBTiles.prototype._setup = function(callback) {
-    var mbtiles = this;
-    mbtiles._exists('tiles', function(err, exists) {
-        if (exists) return callback(null);
-        fs.readFile(__dirname + '/schema.sql', 'utf8', function(err, sql) {
-            if (err) return callback(err);
-            mbtiles._db.exec(sql, callback);
-        });
-    });
+    this._db.exec(MBTiles.schema, callback);
 };
 
 // Select a tile from an mbtiles database. Scheme is XYZ.

lib/schema.sql

@@ -1,5 +1,7 @@
 -- MBTiles schema
 
+BEGIN;
+
 CREATE TABLE IF NOT EXISTS map (
    zoom_level INTEGER,
    tile_column INTEGER,
@@ -70,3 +72,5 @@ CREATE VIEW IF NOT EXISTS grid_data AS
     FROM map
     JOIN grid_key ON map.grid_id = grid_key.grid_id
     JOIN keymap ON grid_key.key_name = keymap.key_name;
+
+COMMIT;