Create a Simple Lookup Table

This tutorial will walk you through the creation of a simple Lookup Table.

In this detailed end-to-end tutorial, we’ll guide you through creating a simple Lookup Table that keeps in one repository the data of different banks, that after is used for transactions. This Lookup Table integrates to a decision table for evaluating a transaction fee according to the bank's country.

How to create a simple lookup table

Let's advance one step at a time.

1. Log in

Becoming a superhero is a fairly straightforward process. After entering our login page, you will be able to pass your credentials and log in.

There are multiple options for user login. If you do not have an account yet, you can create one. After logging in to the application, the folder structure of your Rules List will be displayed.

2. Create a new Decision Table

To display the rules creation list, click the + Create button on the search bar. Select your rule and you will be prompted to provide a name. For this example, we will create a table for Bank Data Catalog, select a name for your rule as you wish and press "Confirm". The new rule will be created and its design interface will be displayed.

3. Make basic settings

Rule Settings will be in a left-hand side menu. Let's do some settings. You can switch the toggle status between Published and Pending. Modify the Rule name or the Alias. Write a short description of the table.

To apply these changes, we have to click the Save button at the top of the page, right corner.

4. Set the columns

To define your data columns, navigate to the first column after the Primary Key. Double-click the header to rename it; enter the name of the first property, i.e. BankName . To expand your table, simply click the "+" sign located next to your rightmost column. You can rename the next column Country with the same method, or using the dropdown menu clicking the small arrow on the header. The last one must contains the specific RoutingMethod , repeat the same steps.

5. Set the rows

Now, begin filling in the information for each bank. In this example, banks are indexed by their unique SWIFT Codes, so the Primary Key must contain these codes. This maps each Swift Code to the critical banking attributes defined in your columns.

Let’s start with "Bank of America":

Swift Code	BankName	Country	RoutingMethod
BOFAUS3N	Bank of America	USA	WIRE_FAST

Click the + Add Row button in the bottom toolbar, and fill in the data for the next bank, for instance JPMorgan Chase. Iterate the process for each new bank you want to add to the table.

You can find a JSON file of this rule containing all countries here below. You may download it and import it directly into your Space.

16KB

Wire_Router_v1.json

Open

6. Using Lookup Tables in Rules

Next, create a Decision Table called Fee Multiplier to calculate transaction fees based on the bank in use. The Input/Output model will be:

// Input model
{
  "swiftCode": {},
  "originCountry": {}
}

// Output model
{
  "feeMultiplier": {},
  "message": {}
}

The table will evaluate two conditions: SWIFT Code Validity and Country of Origin. The three logic scenarios are as follows:

1. Invalid Code: IF the Swift Code does not exist, THEN the transaction is invalid.

2. Domestic Transfer: IF the Code exists and the bank's country matches the originCountry, THEN the transaction is valid with no fee.

3. International Transfer: IF the Code exists but the bank's country is different from the originCountry, THEN the transaction is valid with a 30% fee.

To evaluate these conditions dynamically, add a Calculation Column to retrieve the country data from your Lookup Table. Use the LOOKUP_VALUE() function, which requires four parameters: the table's alias, the primary key, the table version, and the column name.

LOOKUP_VALUE("bank-catalog-alias", {swiftCode}, null,"Country")

You can now use the country retrieved from your Lookup Table to set your conditions. The first condition column validates that the function result is not null; if it is null, the SWIFT code does not exist in our catalog. The second condition column matches the originCountry from the input with the data gathered from the Lookup Table.

Finally, set the results. For the first row, the feeMultiplier is empty (invalid). For the second row, it is 1 (no fee). For the third row, it is 1.3 (representing the 30% increase). You can customize the messages as you see fit.

7. Test the Decision Table

You can now test the functionality of your Lookup Table by evaluating the Decision Table we just created. Open the Test Bench at the bottom of your the designer for your Fee Multiplier Decision Table.

Enter your input data and click the Run button; the results will be displayed on the right-hand side. Note that you can switch between the Simple Bench and the JSON Bench.

For example, using the JSON Bench, input the following data:

{
  "swiftCode": "HBUSGB4B",
  "originCountry": "UK"
}

Upon hitting Run , we will get the following response.

[
  {
    "feeMultiplier": 1,
    "message": "Domestic transfer to UK"
  }
]

More information about Test Bench can be found here.

If you have arrived here, you have successfully completed the tutorial. Congratulations!