Data Strategies

Overview

In the overview you can see all Data Strategies that currently exist. You can search for a specific Data Strategy, adjust the column selection or create a new Data Strategy with the button + Data Strategy.

Creation

Enter a name for the new Data Strategy.

Extracted Data

Left Dropdown	Right Dropdown	Description
New Database	-	dab Nexus creates a new Database after every Run
Keep Database	Overwrite	dab Nexus creates a new database during the first run of a task, then the extracted data is overwritten with each subsequent run
Keep Database	Delta Merge	dab Nexus creates a new database during the first run of a task, then the extracted data is appended to the existing data during each subsequent run
Existing Database	Overwrite	dab Nexus writes the extracted data to an existing database, the data is overwritten with each subsequent run
Existing Database	Delta Merge	dab Nexus writes the extracted data to an already existing database, with each subsequent run its data is appended to the already existing data
Existing Database	New Schema	dab Nexus writes the extracted data to an existing database, a new database schema is created for each subsequent run

• Automatic delection after ... days: define after how many days after a run has been executed the Extracted Data should be deleted
• Database Scheme: name your Data Strategy
• Possibility to overwrite Database schema in Task: if activated, you can adjust the Database schema in Task Creation

Processed Data

Processed Data	Description
Overwrite	The result data of the previous run is overwritten with each run
New Result Set	The result data is written to a new database schema for each run

• Automatic delection after ... days: define after how many days after a run has been executed the Extracted Data should be deleted

• Database Scheme: name your Data Strategy

• Possibility to overwrite Database schema in Task: if activated, you can adjust the Database schema in Task Creation

• Automatically delete database after ... Days: only available if New Database was specified for Input Data

Edit

To edit an existing Data Strategy just click on its name in the overview. You can only adjust the name and the Automatic Deletions.

Deletion

Important

The deletion of a Data Strategy can affect active (scheduled) Tasks and may cause them to fail. This deletion cannot be undone.

Interaction between Data Strategy and Table Strategy

Note

When working on the Table Strategy in Package Studio, make sure you pay attention to the Data Strategy for the Task. The following table will help you understand how these interact with each other and when which Strategy takes effect. Find more information in the section Package Studio of our dab Nexus documentation.

The possible results are:

• Discard: the table is not written to the database
• Layout: an empty table without rows is written to the database
• Overwrite: the table is overwritten with each run
• Merge: the table is merged with new data based on the primary key
• Append: new data will be added to the table
• Once: the table is written once and is neither overwritten nor merged in subsequent runs

Data Strategy vs. Table Strategy - When does what take effect?

Hint

Short example:

• Package: Merge is selected as Table Strategy
• Task: Keep Database - Overwrite is selected as Data Strategy

Result: Overwrite

-	Table Strategy Merge	Table Strategy Overwrite	Table Strategy Append	Table Strategy Layout	Virtual Table
Data Strategy New Database	Once	Once	Once	Layout	Discard
Data Strategy Keep Database - Overwrite	Overwrite	Overwrite	Overwrite	Layout	Discard
Data Strategy Keep Database - Delta Merge	Merge	Overwrite	Append	Layout	Discard
Data Strategy Existing Database - Overwrite	Overwrite	Overwrite	Overwrite	Layout	Discard
Data Strategy Existing Database - Delta Merge	Merge	Overwrite	Append	Layout	Discard
Data Strategy Existing Database - New Schema	Once	Once	Once	Layout	Discard

Replication Task - Data Strategy vs. Table Strategy

When you create a Replication Task, you can choose between Merge and Overwrite.

-	Table Strategy Merge	Table Strategy Overwrite	Table Strategy Append	Table Strategy Layout	Virtual Table
Data Strategy Merge	Merge	Overwrite	Append	Layout	Discard
Data Strategy Overwrite	Overwrite	Overwrite	Overwrite	Layout	Discard