Hi Jenna! You have two options in Trifacta: a lookup or a join.
A lookup (see here: https://docs.trifacta.com/display/PE/Lookup+Wizard) is more akin to a vlookup in Excel. The gist is that for any value in the selected column of your current dataset, the lookup finds any match in the lookup column of your lookup dataset and brings in all of the columns corresponding to that value from the lookup dataset. If there is not a match, the columns from the lookup dataset will be empty for those particular rows.
To perform a lookup:
- Select the drop down for the column you would like to perform the lookup on
- Select the target dataset you would like to lookup against
- Select the column to lookup against in that target dataset
- Execute Lookup
The other, more robust option, is a Join (See here: https://docs.trifacta.com/display/PE/Join+Page). Joins are more in line with SQL joins (if you are familiar). Similar to a lookup, they join data between two datasets based on column matches. Joins, however, give you the option to use multiple join keys (columns to match) and specify inner, left outer, right outer, and full outer joins.
To perform a join:
- Create a new step
- Select Join from the Transformation box
- Select the dataset you would like to join with
- Choose preview to preview the dataset you are joining with
- Select Join keys to choose the columns to join on (Note: Trifacta will attempt to infer the best columns to join on based on name and overall match)
- From this menu, you can edit the join keys, add new join keys, and change the join type. Make sure to select all of the columns you would like included in the result of the join from the Columns panel!
- When you are ready, Add to your recipe.
