Create and Delete Deltas

Create a New Delta

Clicking on Deltas in the left navigation menu shows a list of existing Deltas. Click Create Delta in the top right corner to create a new delta.


Enter a unique name for your Delta.


Select an existing schedule (click the menu to see available choices), no schedule (choose None), or a new schedule (choose Create new schedule).


Select your source table. You can choose any table in the Bigeye catalog, including virtual tables and views. Search by table name to find the table you are looking for. You can view the results list with the source name and schema. The source for data replication and migration use cases must be from where data is copied.

You can compare up to two target tables with the selected source table.

Target A

Add your first target table. You can choose any table from the Bigeye catalog, including virtual tables and views. Search by table name to find the table you are looking for. Results are listed with source name and schema. The target for data replication and migration use cases must be the source where data is copied.

Once you select a table for Target A, the column information automatically populates in the next section.

Column Mapping

Select which columns you'd like to compare between the source and Target A, and Bigeye automatically maps columns with matching names. However, you can remove irrelevant columns and update the mappings as needed.

To remove columns, select Remove on the row with the relevant source column. Removed columns are not considered when the delta is run. Note that you can re-add the column by selecting Add.

To update column mappings:

  1. Select Options > Clear target to remove all of Bigeye's automatic mappings and manually select mappings in target A for each source column. You can select Options > Remap columns to return to the automatic mappings.
  2. Select the dropdown under target columns to select a specific column from the Target A column to match the source column listed. Note that you can only select columns that are not already mapped. Selecting Unmapped removes the column from the comparison.


These changes are permanently saved once you click Create Delta or Save Delta at the bottom of the page. When editing a Delta, you can always click Cancel to revert to the prior Delta definition.

Once columns are mapped, Bigeye automatically applies relevant metrics to evaluate the comparison based on the column type. You can view the number of metrics to be applied in the metrics column.

Advanced Settings > Configuration

Click Show advanced settings to reveal the conditions and group by settings if needed.


Conditions help filter the rows used in the Delta. You can exclude rows from the source that are not in the target. You can limit the Delta to a recent period or a particular data dimension.
Conditions are added to the Deltas' queries as a WHERE clause. Write your filters in the SQL dialect of the source and target table, respectively, and omit the WHERE keyword. You can add conditions to the source table, target table, both tables, or neither, as needed.

Configurations are optional. Your configurations can be different on each table.

Group By

Group By columns are added to a Delta query as a GROUP BY clause.

Group By feature helps understand column differences at a finer grain of dimensionality. You may select more than one column for the grouping.

Selecting columns is optional, but if you select one or more columns on the GROUP BY A side, you must select the same/equivalent columns on the GROUP BY B side. One-sided grouping is not supported.

When you select a column on the A side, its mapped pair (if one exists) automatically populates on the B side. If the A side column is not mapped to a B side column, the value Unmapped appears on the B side. You can change this to an appropriate column.

Target B

If needed, you can add a second target table, Target B. The same source table compares with both Target A and Target B. Click Add target B and follow the same column mapping and advanced settings steps as needed.


Click Notifications to view notification settings. Add email addresses, slack channels, and webhooks. Each time when Delta runs and fails to match, you get a notification on these channels.

Delete a Delta

To delete a single delta, select a delta from the Delta list, and then click Delete.

To delete multiple Deltas, select them with the checkboxes on the left side of the list, and then click Delete.