AlaSQL.js a JavaScript SQL database that handles both traditional relational tables and nested JSON data (NoSQL).
You can export, store, and import data from localStorage, IndexedDB, or Excel.
QueryBuilder can be used on advanced search engine pages, administration backends, etc. to build complex queries or filters. It is highly customisable and can be used with many jQuery widgets like autocompleters and sliders.
It outputs a structured JSON of rules which can be easily parsed to create SQL/NoSQL/whatever queries. It can also directly create a SQL WHERE statement.