Javascripting Help

Hey man, here’s a working copy of my attempt at it

(Edited to add: The code that follows is not as good as it should be, and a newer version can be found two replies later that incorporates the suggestions and fixes that kuovonne provided! Please scroll down and use that one instead!)

Code below:

let table = base.getTable('Table 1')
let newData = [
    {
        title: 'Title 4',
        date: 'Date 4',
        uniqueID: 'unique4'
    },
    {
        title: 'New Title 1',
        date: 'New Date 1',
        uniqueID: 'unique1'
    }
]

let query = await table.selectRecordsAsync({
    fields:['Unique ID']
})

let existingUniqueIDs = new Object

for (let record of query.records){
    let uniqueID = record.getCellValue('Unique ID')
    existingUniqueIDs[uniqueID] = record.id
}

for (let data of newData){
    if(existingUniqueIDs[data.uniqueID]){
        table.updateRecordAsync(existingUniqueIDs[data.uniqueID],{
            "Title": data.title,
            "Date": data.date
        })
    }
    else{
        await table.createRecordAsync({
            "Title": data.title,
            "Date": data.date,
            "Unique ID": data.uniqueID
        });
    }
}```

You’re totally right about the batch updating and creation, as well as the missing await (ha, I just completely missed that sigh)

(Edited to add: with reference to kuovonne’s statement below, the if statements were removed as they were not needed!)

Here’s the new version, and the base has been updated as well:

let table = base.getTable('Table 1')
let newData = [
    {
        title: 'Title 4',
        date: 'Date 4',
        uniqueID: 'unique4'
    },
    {
        title: 'New Title 1',
        date: 'New Date 1',
        uniqueID: 'unique1'
    }
]

let query = await table.selectRecordsAsync({
    fields:['Unique ID']
})

let existingUniqueIDs = new Object

for (let record of query.records){
    let uniqueID = record.getCellValue('Unique ID')
    existingUniqueIDs[uniqueID] = record.id
}

let recordsToCreate = new Array
let recordsToUpdate = new Array

for (let data of newData){
    if(existingUniqueIDs[data.uniqueID]){
        recordsToUpdate.push({
            id: existingUniqueIDs[data.uniqueID],
            fields: {
                "Title": data.title,
                "Date": data.date
            }
        })
    }
    else{
        recordsToCreate.push({
            fields:{
                "Title": data.title,
                "Date": data.date,
                "Unique ID": data.uniqueID
            }
        })
    }
}


while (recordsToCreate.length > 0) {
    await table.createRecordsAsync(recordsToCreate.slice(0, 50));
    recordsToCreate = recordsToCreate.slice(50);
}


while (recordsToUpdate.length > 0) {
    await table.updateRecordsAsync(recordsToUpdate.slice(0, 50));
    recordsToUpdate = recordsToUpdate.slice(50);
}

You don’t need the if statement. It has the same condition as the while. The condition for a while loop is tested before the first iteration of the loop is executed.