Single edits Oracle: Update a Database Using an FME Flow App

Introduction

FME Flow can create Flow Apps that allow users to run a workspace and enter parameters without the need to log in. These apps allow users to update datasets on the fly while out in the field using their mobile phones. In this article, we show you how to setup Oracle and FME Flow to respond to single feature database edits. If a large number of edits are being made, a bulk insert can also be set to push out large quantities of data with a single call. This is described in the following article Bulk Edits Oracle: Update a Database Using an FME Flow App

Requirements

• Access to an Oracle Spatial connection

Step-by-Step Instructions

Part 1: FME Workbench

Before we begin, we will need to open the two workspaces in FME Workbench to change the parameters to our own Oracle database.

1. Open FME Workbench

If you completed the Bulk Edits Oracle article, you can skip to Part 1 - Step 4 as you will already have the table loaded into your database.

First, we need to create a table in our database. Open CreateTableInOracle.fmwt and expand the Oracle writer in the Navigator window. Double-click on Connection to open the connection parameters.

In the Edit ‘Oracle [ORACLE_SPATIAL]’ dialog, click the drop-down next to Connection and click Add Database Connection.

Then add your Oracle database connection parameters. For more information on setting up an Oracle database connection, please see the article Viewing and Inspecting Oracle Data. Once the connection has been added, ensure it is selected, and click OK.

2. Change Table Parameters

There is one more thing to change before we can run this workspace. Double-click on the Oracle Writer feature type to open the Feature Type parameters. Change the Table Qualifier name to the username of your database. For this example, we are using the SUPPORT username. Once that is updated, click OK.

3. Run the workspace

Save the workspace and then run it. This will create a new table in your Oracle database called Tree_Survey.

Go into your Oracle database, or inspect the output in FME to confirm that the table was written correctly.

4. Open Second Workspace

Close the first workspace and then open TreeSurvey.fmw. This workspace will read the database and then based on the user parameters either INSERT, UPDATE, or DELETE the data in the database.

There are a variety of user parameters created to allow user input when we upload this workspace to FME Flow.

Let’s go through what this workspace does:

a. Reads in the Tree_Survey database table created with CreateTableInOracle.fmwt

b. Tests the user parameter $(Tree_ID), if the Tree_ID exists, it will move on to the UPDATE or DELETE section. If it doesn’t exist, it will move to the INSERT section.

c. Has the tree been removed? This is based on the $(Removed) user parameter. If yes, then it triggers the DELETE workflow. If no, then it moves to UPDATE.

d. Joins the $(Tree_ID) user parameter with the Tree_ID attributes in the database to see if the value input for the user parameter exists in the database. If it doesn’t, it moves onto the INSERT workflow

e. Tests the new Tree_ID and if the tree is new. If it is new, then it continues the INSERT workflow, if it is not new, the workspace ends.

f. Sets the additional user parameters to include in the UPDATE or INSERT

g. Sets the database operation with the FME specific attribute fme_db_operation, additionally for DELETE and INSERT it uses a WHERE clause to identify exactly which record to DELETE or INSERT.

h. Writes out to the same Oracle database table as the FeatureReader, and switches the database operation based on the previous AttributeCreators.

i. Cleans up attributes in preparation to write out to a log file.

j. Writes out the Database Operation, Date, and which attributes were written to the database in a Microsoft Excel file. This file can be used to monitor changes to the database.

5. Update FeatureReader

In this second workspace, open the FeatureReader parameters and change the Connection to the Oracle connection you created in the previous workspace. Additionally, click the ellipsis next to Feature Types to Read and select the Tree_Survey in your database. Click OK to close the Feature Reader.

When you update the FeatureReader ensure that the output port yourusername.TREE_SURVEY is connected to the Tester_2.

6. Update Oracle Writer

Next, we will need to update the connection parameters for the Oracle Writer. In the Navigator window, change the Oracle connection to your connection, the same way as the previous workspace.

Once the connection is created, open up the Oracle Writer Feature Type and change the Table Qualifier to the username you used in the previous workspace, in this example, we are using SUPPORT. Also change Table Name, if necessary.

7. Test the Workspace

Before we publish this workspace to FME Flow, it is a good idea to test it locally. Ensure that Prompt for User Parameters is enabled and then run the workspace.

In the Translation Parameter Values dialog enter the following:

• Tree ID: 59152
• Tree Health: EXCELLENT
• Measure the Diameter in Inches: 52
• Has the Tree Been Inspected: Yes
• Civic Number: 1800
• Type in Street: Beach Av
• Has dead tree been removed?: No
• Is this tree new for this year?: No
• Uncheck: Save As User Parameter Default Values

Once the parameters are entered, click Run. This will trigger an UPDATE in the database. You can inspect the database to confirm this update. As well, you can also view the Microsoft Excel TreeLog, which will include the parameters we just set, the database operation UPDATE and today’s date and time.

If you want to test DELETE and INSERT, rerun the workspace and change the following parameters:

For DELETE:

Has dead tree been removed?: Yes

For INSERT

Tree ID: 1482749

Is this tree new for this year?: Yes

For INSERT, due to the current published parameters, not all of the attributes will have a value such as LATITUDE, LONGITUDE, or CURB. If you would like to add values to these attributes, create a published parameter for each and set them in the AttributeManager_2 in bookmark f.

8. Publish to FME Flow

Once you have confirmed that this workspace runs successfully with your database connection, it is time to publish it to FME Flow.

Before publishing to FME Flow, you need to decide if you want your Excel log file to be available to the user running the Flow App. If you do not, you can either leave the Excel file to be updated locally on your machine OR you can set it up to update in the FME Flow Resources folder.

To update the file to save it to FME Flow, expand the TreeDatabase-LogReport writer in the Navigator window. Then double-click on the Destination Microsoft Excel File parameter to open up the edit dialog. In the edit dialog, click on the drop-down next to Destination Microsoft Excel File, then choose User Parameter > FME Flow Parameters > FME_SHAREDRESOURCE_DATA. Then after $(FME_SHAREDRESOURCE_DATA) type in \FlowApps\TreeDatabase-LogReport.xlsx

$(FME_SHAREDRESOURCE_DATA)\FlowApps\TreeDatabase-LogReport.xlsx

Click OK. Save the workspace, and then click on the Publish icon in the top toolbar.

In the Publish to FME Flow dialog, create an FME Flow connection if you do not already have one. Then ensure this workspace is saved to a Repository called FlowApps. Be sure to upload your Oracle connection. Then register with the Job Submitter service if you want your log file private and/or the Data Download service if you want the log file to be public. The Data Download service will download the log Excel file every time the app is run.

Part 2: FME Flow

With the workspace published, we can create an FME Flow App. An FME Flow App allows users to run an FME Flow workspace without logging in. It also allows the user to run the workspace on their mobile phone. For more information on FME Flow Apps, please see the article Getting Started with FME Flow Apps.

1. Log into FME Flow

Log into FME Flow with an account that has privileges to create FME Flow Apps. Once logged in, go to the Flow Apps section and then click on Create.

Additionally, you can create an FME Flow App through the Run Workspace Page Advanced section.

2. Create FME Flow App

On the Create Flow App page, give your app a name and short description. Then select the Repository and Workspace.

Choose which Service you want to use. Remember if you want your log file public, use the Data Download service, if you want it private, use the Job Submitter.

Next, check the Expiration date. By default, apps are set to expire in 10 years. It might be a good idea to set this expiration date to a shorter time. This expiration time can be changed at any time.

Now expand the Parameters section, and double-check the defaults for the app. If your parameters have values next to them, click on the Reset button. By setting all the values to blank, this will ensure that the user doesn’t miss a parameter when they enter their own values. Also ensure that all of the desired parameters are being shown in the app, which is indicated by the green checkmark next to each parameter.

Finally, you can expand the Customize Appearance section and add color, text, or images to your final app page.

Once you are satisfied with your app, click OK. You will get a URL that links to your app.

3. Test App

Click on the URL that was provided at the end up the app setup.

To share the FME Flow App with anyone, the FME Flow must be accesses externally, not internally using localhost.

If you navigated away from the page with the URL, you can access it again by going to Flow Apps on the side menu and then clicking on the URL icon next to your app name.

To test the Flow App, enter the following parameters:

• Tree ID: 113783
• Tree Health: POOR
• Measure the Diameter in Inches: 10
• Has the Tree Been Inspected: Yes
• Civic Number: 784
• Type in Street: Thurlow St
• Has dead tree been removed?: No
• Is this tree new for this year?: No

You can also change the parameters to trigger a DELETE or INSERT.

Data Attribution

The data shown here originates from open data made available by the City of Vancouver, British Columbia. It contains information licensed under the Open Government License - Vancouver.