Drop Duplicate Rows

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The Drop Duplicate Rows Node performs the equivalent to a "Select DISTINCT" operation on the current Data Table. Rows that are considered to be duplicates of other rows are removed. A duplicate row is one that contains identical values as another row.

Please see the example below, of a Data Table before and after executing a Drop Duplicate Rows Node (rows which will be deleted are marked with a red cross).

Remove duplicates illustration.png

Selecting columns to consider

The following dialog is displayed when dragging this Node into your Task:

Drop duplicates editor.png

Select which columns you wish to be considered when comparing rows. Any columns which are left unchecked will be ignored when making the comparison - meaning that even though those values differ, provided the checked columns are identical the row will be dropped.

In the example screenshot above only the FORENAME, SURNAME, COMPANY and ORDER_NUMBER will be considered for identicality. Rows containing equal values for these but differing values for DELIVERY_DATE will be dropped (the first row will be retained).

Data Filter | Require Columns | Append Data Column | Multiple Column Appender

Drop Column | Drop Row(s) | Calculate Column Aggregate | Dataset Splitter | Merge Data

Create Data Table | Clear Data Table | Sort Data Table | Drop Duplicate Rows | Store Data Table | Retrieve Data Table

Task Elements > Data Table Nodes > Drop Duplicate Rows