# Creating Database Lookup Maps

The Database Lookup map uses a database table containing both lookup values and output values. Database lookup can be performed based on a single lookup field, or a combination of fields. Similarly, Database Lookup can return a single output field from the database lookup table, or a combination of fields. In either case, the output field (or fields) are returned from the record in which the lookup value (or values) matched the incoming value (or values).

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If there is no match for an incoming value (or values), Database Lookup object can trigger an error for that record or generate a warning while returning a null value in the output field (or fields).

For example, the source contains names of states in abbreviated format (e.g. CA for California, NM for New Mexico, etc) in State\_Abbr field, which you need to convert into fully spelled-out states in State field (e.g. California or Texas).

In this example, State\_Abbr is the lookup field, and State is the output field.

To add a Database Lookup mapping, drag the *Database Lookup* object from the *Maps* group in the Flow toolbox and drop it on the dataflow.

An example of what a *Database Lookup* object might look like is shown below:

![](/files/aBy5RbhjBSkWP5DlNCol)

To configure the properties of a *Database Lookup* object after it was added to the dataflow, right-click on it and select *Properties* from the context menu. The following properties are available:

* *Database Info*: Using this control, specify the connection information to the database storing your database lookup table.
  * *Pick Table* – select the database lookup table.
    * Add any additional WHERE clause input allows you to specify an additional filter for the lookup table. For example WHERE State\_Abbr <> ‘HI’
  * *Add Warning and Proceed* – select this option if you want the Database Lookup to generate a warning and return a null value in the output field(s) when there is no match in the lookup field(s).
  * *Add Error Message* – select this option if you want the Database Lookup to trigger an error for the records that have no match in the lookup field(s).
* *General Options screen:* This screen shares the options common to most objects on the dataflow.

## **Usage**

In the following example, a database lookup object is used to look up incoming data by SupplierId and Billing Postal Code. Whenever there is a match, the database lookup object outputs MasterRecordId, Name, Type, and ParentId which are then written to a delimited file.

![](/files/fb1AeLj96l40IHOOfMim)


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