diff --git a/lib/sql.js b/lib/sql.js
index dcad57a..0c6b349 100644
--- a/lib/sql.js
+++ b/lib/sql.js
@@ -273,6 +273,24 @@ SqlConnector.prototype._escapeIdValue = function(model, idValue) {
   }
 };
 
+function buildWhere(self, model, where) {
+  if (typeof self.buildWhere === 'function') {
+    return self.buildWhere(model, where);
+  } else {
+    var props = self._models[model].properties;
+    var cs = [];
+    Object.keys(where || {}).forEach(function (key) {
+      var keyEscaped = self.columnEscaped(model, key);
+      if (where[key] === null) {
+        cs.push(keyEscaped + ' IS NULL');
+      } else {
+        cs.push(keyEscaped + ' = ' + self.toDatabase(props[key], where[key]));
+      }
+    });
+    return cs.length ? ' WHERE ' + cs.join(' AND ') : '';
+  }
+}
+
 /**
  * Delete all model instances
  *
@@ -280,11 +298,14 @@ SqlConnector.prototype._escapeIdValue = function(model, idValue) {
  * @param {Function} callback The callback function
  */
 SqlConnector.prototype.deleteAll =
-SqlConnector.prototype.destroyAll = function destroyAll(model, callback) {
-  this.command('DELETE FROM ' + this.tableEscaped(model), function (err, result) {
-    if (callback) callback(err, result);
-  });
-};
+  SqlConnector.prototype.destroyAll = function destroyAll(model, where, callback) {
+    this.command('DELETE FROM ' + this.tableEscaped(model) +
+      buildWhere(this, model, where), function (err, result) {
+      if (callback) {
+        callback(err, result);
+      }
+    });
+  };
 
 /**
  * Count all model instances by the where filter
@@ -295,28 +316,15 @@ SqlConnector.prototype.destroyAll = function destroyAll(model, callback) {
  */
 SqlConnector.prototype.count = function count(model, callback, where) {
   var self = this;
-  var props = this._models[model].properties;
 
+  var whereClause = buildWhere(self, model, where);
   this.queryOne('SELECT count(*) as cnt FROM ' +
-    this.tableEscaped(model) + ' ' + buildWhere(where), function (err, res) {
+    this.tableEscaped(model) + ' ' + whereClause, function (err, res) {
     if (err) {
       return callback(err);
     }
     callback(err, res && res.cnt);
   });
-
-  function buildWhere(conds) {
-    var cs = [];
-    Object.keys(conds || {}).forEach(function (key) {
-      var keyEscaped = self.columnEscaped(model, key);
-      if (conds[key] === null) {
-        cs.push(keyEscaped + ' IS NULL');
-      } else {
-        cs.push(keyEscaped + ' = ' + self.toDatabase(props[key], conds[key]));
-      }
-    });
-    return cs.length ? ' WHERE ' + cs.join(' AND ') : '';
-  }
 };
 
 /**
@@ -400,3 +408,23 @@ SqlConnector.prototype.createTable = function (model, cb) {
     ' (\n  ' + this.propertiesSQL(model) + '\n)', cb);
 };
 
+/**
+ * Update all instances that match the where clause with the given data
+ * @param {String} model The model name
+ * @param {Object} data The property/value object representing changes to be made
+ * @param {Function} callback The callback function
+ */
+SqlConnector.prototype.update =
+  SqlConnector.prototype.updateAll = function (model, where, data, callback) {
+    var whereClause = buildWhere(this, model, where);
+
+    var sql = 'UPDATE ' + this.tableEscaped(model) + ' SET ' +
+      this.toFields(model, data) + ' ' + whereClause;
+
+    this.query(sql, function (err, result) {
+      if (callback) {
+        callback(err, result);
+      }
+    });
+  };
+