This article briefly introduces how to do transformation for Key Columns in Talend Cloud Data Integration
How To
Select the Replication Task, open the task and apply Global Transformation rules by clicking on "Add Transformation Rule" for the Replace Column value. Apply transformation for the key column.
TransformationRule
Add a rule in the expression builder.
RuleExpressionBuilder
Rule gets added for the Primary key column because the PK is defined in the Source.
Expression
Suppose if applying same rule for another table where PK is not defined.And you explicitly define PK in the UI, you can notice that Rule has not been applied to the Primary key Column because the Global Rules will look in the source if the PK is defined or not, if defined it will add the rule for the corresponding PK Column.
Expression2
To add the rule for the column, you need to go to expression builder at the table level and add the condition.
Condition
Now you can see the Rule been added to the PK column which explicitly defined.