Qt 5.9 | Qt Quick | Qt Quick Examples - Local Storage | Database.js Example File

Qt 5.9.9 Reference Documentation

# 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])
          })
      }