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Updating Target Table in Informatica

Generally, in every project we will see at least one requirement to update target based on some conditions.

Case1: When we have primary key defined on table in Database
Case2:  When we do not have primary key defined on table in Database
Case3: When we want to update target based on non-primary key field.

Let’s discuss it in detail.
Case1: When we have primary key defined on table in Database
After creating table in DB, import table as target along with primary key constraints. After done with importing, we can check the primary key details by editing target in target definition.
In this case, we can use update strategy to update target table.
Suppose, we have a table called RETURN_CD and primary key ROW_WID defined on that table. Now, we can update target table using update strategy based on primary key. In mapping, we should connect primary key port and the ports which we want to update in target table. Please check the below screenshot.


And if we edit update strategy in mapping, we can “update strategy expression” property. When we want to update target, we should set it to DD_UPDATE.

When you are using update strategy, we should “check” update as update property in target properties in session.





Case2:  When we do not have primary key defined on table in Database
If we do not have primary key defined on table in database, after importing target in to informatica target definition, edit the target and set primary key in informatica level as per your requirement.
When we edit target, we can see KEY TYPE as NOT A KEY. So, we should change it to primary key.


Once we set primary key in informatica level, follow the same process to update target table as we saw it in CASE1. Even if we create primary key in informatica level then also target table will be updated correctly.

Case3: When we want to update target based on non-primary key field.
In the above two cases, we have seen how we can update target using primary keys. Now, let’s discuss how can we update target using non-primary key fields.
After done with creation of mapping, if we edit target, we can see Target Update Override property.


And we can write update query like below.

UPDATE TARGET_TABLE_NAME
SET TARGET_COLUMN1 = :TU.INCOMING_PORT1,
    [Additional update columns]
WHERE TARGET_COLUMN = :TU.INCOMING_PORT
AND   [Additional conditions]

Or we can click on “generate SQL” and then we can modify query as per requirement.

If you have any questions, please feel free to write to kkrishnareddychp@gmail.com

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