Publish Reports with Google Cloud Storage Data in Crystal Reports

Crystal Reports has many options for offloading data processing to remote data; this enables real-time reporting. The CData ODBC Driver for Google Cloud Storage brings this capability to Crystal Reports. This article shows how to create a report on Google Cloud Storage data that refreshes when you run the report.

Connect to Google Cloud Storage Data

If you have not already, first specify connection properties in an ODBC DSN (data source name). This is the last step of the driver installation. You can use the Microsoft ODBC Data Source Administrator to create and configure ODBC DSNs.

Authenticate with a User Account

You can connect without setting any connection properties for your user credentials. After setting InitiateOAuth to GETANDREFRESH, you are ready to connect.

When you connect, the Google Cloud Storage OAuth endpoint opens in your default browser. Log in and grant permissions, then the OAuth process completes

Authenticate with a Service Account

Service accounts have silent authentication, without user authentication in the browser. You can also use a service account to delegate enterprise-wide access scopes.

You need to create an OAuth application in this flow. See the Help documentation for more information. After setting the following connection properties, you are ready to connect:

• InitiateOAuth: Set this to GETANDREFRESH.
• OAuthJWTCertType: Set this to "PFXFILE".
• OAuthJWTCert: Set this to the path to the .p12 file you generated.
• OAuthJWTCertPassword: Set this to the password of the .p12 file.
• OAuthJWTCertSubject: Set this to "*" to pick the first certificate in the certificate store.
• OAuthJWTIssuer: In the service accounts section, click Manage Service Accounts and set this field to the email address displayed in the service account Id field.
• OAuthJWTSubject: Set this to your enterprise Id if your subject type is set to "enterprise" or your app user Id if your subject type is set to "user".
• ProjectId: Set this to the Id of the project you want to connect to.

The OAuth flow for a service account then completes.

When you configure the DSN, you may also want to set the Max Rows connection property. This will limit the number of rows returned, which is especially helpful for improving performance when designing reports and visualizations.

You can then follow the procedure below to use the Report Wizard to create the Google Cloud Storage connection.

1. In a new report, click Create New Connection -> ODBC.

2. In the resulting wizard, click Select Data Source and select the DSN in the Data Source Name menu.

Design a Report

After adding a ODBC connection to Google Cloud Storage, you can then use the Report Wizard to add Google Cloud Storage data to your report.

1. Click File -> New -> Standard Report.
2. Expand the ODBC node under Create New Connection and double-click Make a New Connection.

3. Configure the data source by selecting the tables and fields needed in the report. This example uses the Name and OwnerId columns from the Buckets table.

You can then configure grouping, sorting, and summaries. For example, this article groups on Name and summarizes on OwnerId. See the following section to use the aggregate and summary to create a chart.

Create a Chart

After selecting a column to group by, the Standard Report Creation Wizard presents the option to create a chart. Follow the steps below to create a chart that aggregates the values in the Name column.

1. In the Standard Report Creation Wizard, select the Bar Chart option and select the column you grouped by, Name in this example, in the On Change Of menu.
2. In the Show Summary menu, select the summary you created.
3. Select filters and a template, as needed, to finish the wizard.

Preview the finished report to view the chart, populated with your data. If you want to filter out null values, use a SelectionFormula.

Working with Remote Data

To ensure that you see updates to volatile data, click File and clear the "Save Data with Report" option. As you interact with the report, for example, drilling down to hidden details, Crystal Reports executes SQL queries to retrieve the data needed to display the report. To reload data you have already retrieved, refresh or rerun the report.

You can offload processing onto the driver by hiding details elements and enabling server-side grouping. To do this, you will need to have selected a column to group on in the report creation wizard.

1. Click File -> Report Options and select the Perform Grouping On Server option.
2. Click Report -> Section Expert and select the Details section of your report. Select the Hide (Drill-Down OK) option.

When you preview your report with the hidden details, Crystal Reports executes a GROUP BY query. When you double-click a column in the chart to drill down to details, Crystal Reports executes a SELECT WHERE query that decreases load times by retrieving only the data needed.