The Web SQL Database standard never saw the light of day. It was first formulated, then deprecated by the W3C and was only implemented in some browsers. (It is not supported in Firefox or IE.)
Further, the use of a Web SQL Database poses security concerns, since you only need its name to access such a database.
var db = window.openDatabase("myDb", "1.0", "Personal secrets stored here", 2*1024*1024); // Noncompliant