Database.js Example File | Qt Quick 5.12.10

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- Database.js Example File
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# Database.js Example File

localstorage/localstorage/Database.js

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     function dbInit()
     {
         var db = LocalStorage.openDatabaseSync("Activity_Tracker_DB", "", "Track exercise", 1000000)
         try {
             db.transaction(function (tx) {
                 tx.executeSql('CREATE TABLE IF NOT EXISTS trip_log (date text,trip_desc text,distance numeric)')
             })
         } catch (err) {
             console.log("Error creating table in database: " + err)
         };
     }

     function dbGetHandle()
     {
         try {
             var db = LocalStorage.openDatabaseSync("Activity_Tracker_DB", "",
                                                    "Track exercise", 1000000)
         } catch (err) {
             console.log("Error opening database: " + err)
         }
         return db
     }

     function dbInsert(Pdate, Pdesc, Pdistance)
     {
         var db = dbGetHandle()
         var rowid = 0;
         db.transaction(function (tx) {
             tx.executeSql('INSERT INTO trip_log VALUES(?, ?, ?)',
                           [Pdate, Pdesc, Pdistance])
             var result = tx.executeSql('SELECT last_insert_rowid()')
             rowid = result.insertId
         })
         return rowid;
     }

     function dbReadAll()
     {
         var db = dbGetHandle()
         db.transaction(function (tx) {
             var results = tx.executeSql(
                         'SELECT rowid,date,trip_desc,distance FROM trip_log order by rowid desc')
             for (var i = 0; i < results.rows.length; i++) {
                 listModel.append({
                                      id: results.rows.item(i).rowid,
                                      checked: " ",
                                      date: results.rows.item(i).date,
                                      trip_desc: results.rows.item(i).trip_desc,
                                      distance: results.rows.item(i).distance
                                  })
             }
         })
     }

     function dbUpdate(Pdate, Pdesc, Pdistance, Prowid)
     {
         var db = dbGetHandle()
         db.transaction(function (tx) {
             tx.executeSql(
                         'update trip_log set date=?, trip_desc=?, distance=? where rowid = ?', [Pdate, Pdesc, Pdistance, Prowid])
         })
     }

     function dbDeleteRow(Prowid)
     {
         var db = dbGetHandle()
         db.transaction(function (tx) {
             tx.executeSql('delete from trip_log where rowid = ?', [Prowid])
         })
     }