Databases 11/16

In Google app engine databases work by using GQL to store or access elements of an entity. Entities may contain one or more properties which has a name and a specified data type. All properties are stored within an entity in the form of a table. Each entity is identified by its kind which is specified in the name of the class which creates the entity and a key which is unique. The Google App Engine datastores do not update instantaneously so accessing an element which was just entered into the datawstore can result in problems. The GQL syntax which is very similar to SQL is used to retrieve entities or keys from the datastore.