A very simple snippet for web-tools to run queries against sql.js database stored in localStorage

sql.manager.js

(function(DBName) {

var raw_DB = localStorage.getItem(DBName);

if (raw_DB) {
    window._db = (function(raw) {
      let db = new SQL.Database(JSON.parse(raw));
      return {
        run: function(sql) {
            let data = db.exec(sql);
            if (data.length == 0) {
                console.log('SQL returns empty result');
                return;
            }

            let cols = data[0].columns;
            let result = data[0].values.map((row) => {
                let res = {};
                cols.forEach( (col, i) => {
                    res[col] = row[i]
                });
                return res;
            });

            console.table(result);
        },

        tables: function() {
           this.run('SELECT name FROM sqlite_master WHERE type="table" ORDER BY name;');
        },

        columns: function(tableName) {
            this.run(`pragma table_info("${tableName}")`); 
        },

        view: function(tableName, max = 0) {
            this.run(`SELECT * FROM ${tableName}` + (max > 0 ? ` LIMIT ${max}`: ''));
        }
      };
    })(raw_DB);
}
})('{{DB_NAME}}');