I want to change my data-tables values which are null to empty strings.
Sometimes the department value will be empty, in which case it will put null in my data tables.
db = db_open();
db.fuel.toArray().then(fuel => {
fuel.forEach(function(fuel) {
$('#table_bod').append('<tr> <td>'+fuel.department+'</td> </tr> ');
})
});
I tried:
const fuels = db.fuel.where({department: null});
But that doesn't seem to work.
IndexedDB cannot match against null so in order to find those you must do a full table scan.
const fuelsWithoutDepartment = await db.fuel
.filter(x => x.department === null)
.toArray();
Create an upgrader that modifies all null departments to empty string in case you want to have that instead of null.
db.version(2).stores({
fuel: 'id, department'
}).upgrade (tx => {
return tx.fuel.filter(
x => x.department === null
).modify({department: ""});
});
Once you've declared such an upgrader (please adjust it to the appropriate version, id and indexes for your case), then you won't need a full table scan to find fuels without departments anymore but can use the department index (if you have one):
const fuelsWithoutDepartment = await db.fuel
.where({department: ""})
.toArray();