2.5.1 Update Existing Index

Impulse does not support row level updates. You can overwrite partitions within a specific data range and add new data to existing index. Here is an example of how this works:

Assume you have an existing index in Impulse with the following rows:

Date	Employee	Salary
2019-01-01	John	6000
2019-01-02	Sara	6100
2019-01-03	Smith	6200
2019-01-04	Bob	6300

If we have the following dataset that we want to append to existing index and update the existing partitions within the period 2019-01-01 and 2019-01-03:

Date	Employee	Salary
2019-01-01	Jessica	7000
2019-01-02	Sara	7100
2019-01-03	Simpson	7200
2019-01-04	Robert	7300
2019-01-05	Dave	7400

The resultant data after the combine and overwrite of partitions within the period 2019-01-01 and 2019-01-03 will be:

Date	Employee	Salary
2019-01-01	John	7000
2019-01-01	Jessica	7000
2019-01-02	Sara	7100
2019-01-03	Simpson	7200
2019-01-04	Bob	6300
2019-01-04	Robert	7300
2019-01-05	Dave	7400

Notice that the partitions within the date range 2019-01-01 and 2019-01-03 are replaced by the the new dataset and outside this date range the data are appended to existing index.

Here are the steps to combine and overwrite the existing partitions.

1. Follow the steps of ingesting files to a datasource in a warehouse
2. In the step 2, select the Upload Mode as “Combine & Overwrite: Combine old data with new data and overwrite” option from the dropdown list (see Figure 2.5.1a below)
3. In the partition overwrite period from and to fields, fill out the data range that you want your new data to update to.
4. Follow the remaining steps of ingesting data into Impulse.