*** Datasets must be sorted on key variables prior to merging. ***

Open 1to1 left.sav                         Open 1to1 right.sav 

Go to 1to1 left.sav → Data → Merge Files → Add Variables

A keyed table (also called lookup table) has two basic characteristics:

1. A keyed table has to have unique cases based on the key variable(s).
2. A keyed table doesn't contribute cases to the merged file. It contributes variables only.

Of note: For SPSS 28, you will have to mark the merge method as a "one-to-many merge based on key values" to select the Lookup Table

1. Selecting the non-active dataset will merge values from second dataset to the to the first dataset based on the key

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