Google BigQuery is a serverless, highly scalable, and cost-effective data warehouse designed to help organizations turn big data into actionable insights.
The CData SSIS Components enhance SQL Server Integration Services by enabling users to easily import and export data from various sources and destinations.
In this article, we explore the data type mapping considerations when exporting to BigQuery and walk through how to migrate Cvent data to Google BigQuery using the CData SSIS Components for Cvent and BigQuery.
Data Type Mapping
| Google BigQuery Schema |
CData Schema |
|
STRING, GEOGRAPHY, JSON, INTERVAL
|
string
|
|
BYTES
|
binary
|
|
INTEGER
|
long
|
|
FLOAT
|
double
|
|
NUMERIC, BIGNUMERIC
|
decimal
|
|
BOOLEAN
|
bool
|
|
DATE
|
date
|
|
TIME
|
time
|
|
DATETIME, TIMESTAMP
|
datetime
|
|
STRUCT
|
See below
|
|
ARRAY
|
See below
|
STRUCT and ARRAY Types
Google BigQuery supports two kinds of types for storing compound values in a single row, STRUCT and ARRAY. In some places within Google BigQuery, these are also known as RECORD and REPEATED types.
A STRUCT is a fixed-size group of values that are accessed by name and can have different types. The component flattens structs so their fields can be accessed using dotted names. Note that these dotted names must be quoted.
An ARRAY is a group of values with the same type that can have any size. The component treats the array as a single compound value and reports it as a JSON aggregate. These types may be combined such that a STRUCT type contains an ARRAY field, or an ARRAY field is a list of STRUCT values.
Special Considerations
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Google BigQuery has both DATETIME (no timezone) and TIMESTAMP (with timezone) data types that the CData SSIS Components map to datetime based on the timezone of your local machine.
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In Google BigQuery, the NUMERIC type supports 38 digits of precision and up to 9 digits after the decimal point, while the BIGNUMERIC type supports 76 digits of precision and up to 38 digits after the decimal point. The CData SSIS Components for Google BigQuery automatically detects the precision/scale, but with the Destination Component users can manually map any high-precision columns.
-
INTERVAL data types:
Prerequisites
Create the project and add components
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Open Visual Studio and create a new Integration Services Project.
π Create the SSIS project
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Add a new Data Flow Task to the Control Flow screen and open the Data Flow Task.
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Add a CData Cvent Source control and a CData GoogleBigQuery Destination control to the data flow task.
π Add the source and destination controls (Salesforce is shown)
Configure the Cvent source
Follow the steps below to specify properties required to connect to Cvent.
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Double-click the CData Cvent Source to open the source component editor and add a new connection.
π Open the source component editor (Salesforce is shown)
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In the CData Cvent Connection Manager, configure the connection properties, then test and save the connection.
Before you can authenticate to Cvent, you must create a workspace and an OAuth application.
Creating a Workspace
To create a workspace:
- Sign into Cvent and navigate to App Switcher (the blue button in the upper right corner of the page) >> Admin.
- In the Admin menu, navigate to Integrations >> REST API.
- A new tab launches for Developer Management. Click on Manage API Access in the new tab.
- Create a Workspace and name it. Select the scopes you would like your developers to have access to. Scopes control what data domains the developer can access.
- Choose All to allow developers to choose any scope, and any future scopes added to the REST API.
- Choose Custom to limit the scopes developers can choose for their OAuth apps to selected scopes. To access all tables exposed by the driver, you need to set the following scopes:
| event/attendees:read | event/attendees:write | event/contacts:read |
| event/contacts:write | event/custom-fields:read | event/custom-fields:write |
| event/events:read | event/events:write | event/sessions:delete |
| event/sessions:read | event/sessions:write | event/speakers:delete |
| event/speakers:read | event/speakers:write | budget/budget-items:read |
| budget/budget-items:write | exhibitor/exhibitors:read | exhibitor/exhibitors:write |
| survey/surveys:read | survey/surveys:write |
Creating an OAuth Application
After you have set up a Workspace and invited them, developers can sign up and create a custom OAuth app. See the Creating a Custom OAuth Application section in the Help documentation for more information.
Connecting to Cvent
After creating an OAuth application, set the following connection properties to connect to Cvent:
- InitiateOAuth: GETANDREFRESH. Used to automatically get and refresh the OAuthAccessToken.
- OAuthClientId: The Client ID associated with the OAuth application. You can find this on the Applications page in the Cvent Developer Portal.
- OAuthClientSecret: The Client secret associated with the OAuth application. You can find this on the Applications page in the Cvent Developer Portal.
π Configure the source connection (Salesforce is shown)
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After saving the connection, select "Table or view" and select the table or view to export into Google BigQuery, then close the CData Cvent Source Editor.
π Select the table to export (Salesforce is shown)
Configure the Google BigQuery destination
With the Cvent Source configured, we can configure the Google BigQuery connection and map the columns.
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Double-click the CData Google BigQuery Destination to open the destination component editor and add a new connection.
π Open the destination component editor
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In the CData GoogleBigQuery Connection Manager, configure the connection properties, then test and save the connection.
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Google uses the OAuth authentication standard. To access Google APIs on behalf of individual users, you can use the embedded credentials or you can register your own OAuth app.
OAuth also enables you to use a service account to connect on behalf of users in a Google Apps domain. To authenticate with a service account, register an application to obtain the OAuth JWT values.
In addition to the OAuth values, specify the DatasetId and ProjectId. See the "Getting Started" chapter of the help documentation for a guide to using OAuth.
Helpful connection properties
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QueryPassthrough: When this is set to True, queries are passed through directly to Google BigQuery.
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ConvertDateTimetoGMT: When this is set to True, the components will convert date-time values to GMT, instead of the local time of the machine.
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FlattenObjects: By default the component reports each field in a STRUCT column as its own column while the STRUCT column itself is hidden. When this is set to False, the top-level STRUCT is not expanded and is left as its own column. The value of this column is reported as a JSON aggregate.
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SupportCaseSensitiveTables: When this property is set to true, tables with the same name but different casing will be renamed so they are all reported in the metadata. By default, the provider treats table names as case-insensitive, so if multiple tables have the same name but different casing, only one will be reported in the metadata.
π Configure the destination connection
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After saving the connection, select a table in the Use a Table menu and in the Action menu, select Insert.
π Choose the destination table
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On the Column Mappings tab, configure the mappings from the input columns to the destination columns.
π Map the columns (Salesforce is shown)
Run the project
You can now run the project. After the SSIS Task has finished executing, data from your SQL table will be exported to the chosen table.