HTML5 Client Storage: WebSqlDatabase vs. WebStorage vs. Indexed Database

I have some questions concerning the abilities of client storage in HTML5. From what I've found so far there are three different possibilities:

• WebSQLDatabase: Supports client site SQL-Tables, which are stored in a SQLite Database. This standard is discontinued. Does this mean that browsers that currently support this will drop this support in the future?

• WebStorage 开发者_开发百科and IndexedDB seems quite similar to me. They both offer key/value-store capabilities. Where is the difference?

WebSQLDatabase: Does this mean that browsers that currently support this will drop this support in the future?

Ans: After looking at this post, it seems like safari put this work on hold, as they have stopped comments and ping backs. Also refer to this and this, Chrome will surely put current api in deprecated status. In future versions, once IndexedDB API completely implemented, they may drop the support.

WebStorage and IndexedDB.. Where is the difference?

Ans: WebStorage has some storage mechanisms like sessionStorage, localStorage etc. each has key/value pair like storage. localStorage is of HTML5 feature which uses SQLite database, but with one table and two fields (key and value). Whereas using IndexedDB you can create the number of databases with number of tables..

WebSQLDatabase has been dropped because of the main security issue. e.g. cross-origin attack. see