SQL Server CDC

Overview

You can use this Snap to retrieve data from SQL Server Database transaction logs. It performs Insert, Update, and Delete statements on a specific table within a specified date and time range. It includes the following key features:

  • Transaction retrieval: The Snap retrieves transactions executed on a table. It can handle Insert, Update, and Delete transactions.
  • Flexible time range: You can specify the start and end dates for the logs to analyze the data.

  • Polling interval handling: You can specify a polling interval for the Snap. If a timeout is set, the Snap will process transaction logs at intervals specified by the polling interval.


SQL Server CDC Overview

Prerequisites

  • A valid account with the required SYSADMIN permissions.
  • SQL Server database to be set up for appropriate logging.

Snap views

View Description Examples of upstream and downstream Snaps
Input This Snap supports at the most one document input view. Any Snap with document view.
Output This Snap supports a maximum of one document output view. The output is a document with all the statement data. Any Snap with document view.
Error

Error handling is a generic way to handle errors without losing data or failing the Snap execution. You can handle the errors that the Snap might encounter when running the pipeline by choosing one of the following options from the When errors occur list under the Views tab. The available options are:

  • Stop Pipeline Execution Stops the current pipeline execution when an error occurs.
  • Discard Error Data and Continue Ignores the error, discards that record, and continues with the remaining records.
  • Route Error Data to Error View Routes the error data to an error view without stopping the Snap execution.

Learn more about Error handling in Pipelines.

Snap settings

Legend:
  • Expression icon (): Allows using JavaScript syntax to access SnapLogic Expressions to set field values dynamically (if enabled). If disabled, you can provide a static value. Learn more.
  • SnapGPT (): Generates SnapLogic Expressions based on natural language using SnapGPT. Learn more.
  • Suggestion icon (): Populates a list of values dynamically based on your Snap configuration. You can select only one attribute at a time using the icon. Type into the field if it supports a comma-separated list of values.
  • Upload : Uploads files. Learn more.
Learn more about the icons in the Snap settings dialog.
Field / Field set Type Description
Label String

Required. Specify a unique name for the Snap. Modify this to be more appropriate, especially if more than one of the same Snaps is in the pipeline.

Default value: SQL Server CDC

Example: Employee Table CDC
Database schema String/Expression/ Suggestion

Required. Specify the user schema where the table is located.

Suggestions are available when a list of users is retrieved directly from the database and accessible users are included.

Default value: N/A

Example: HR
Table name String/Expression/ Suggestion

Specify the name of the database table on which the Change Data Capture (CDC) is performed.

Default value: N/A

Example: Employees
Transaction type Dropdown list
Required. Choose the type of statements to retrieve. The available options are:
  • All: Processes all statements type (Insert, Update, Delete)
  • Insert: Retrieves only insert statements.
  • Update: Retrieves only update statement.
  • Delete: Retrieves only delete statement.

Default value: ALL

Example: Update
Start time from which to log the data changes Integer/Expression

Specify the start date and time for the change logs. The format is: yyyy-mm-ddThh:mm:ss.SSSZ

Default value: N/A

Example: 2025-01-01T00:00:01.000Z
End time until which to log the data changes Integer/Expression Specify the end date and time for changes. The format is: yyyy-mm-ddThh:mm:ss.SSSZ

Default value: N/A

Example: 2025-01-31T23:59:59.999Z
Polling mode Checkbox

Select this checkbox to continously poll data. The start and end times defined in the settings enables precise filtering of the data changes captured.

Default status: Deselected

Polling interval String/Expression

Appears when you select the Polling mode checkbox.

Specify the interval to continuously retrieve data changes at specific interval. This mode continuously retrieves data changes at defined intervals. This value represents the frequency of data polling.

Default value: N/A

Example: 15
Polling unit String/Expression

Appears only when you select the Polling mode checkbox.

Choose the unit of time for the polling interval. The available options are:
  • HOURS
  • MINUTES
  • SECONDS

Default value: N/A

Example: HOURS
Last processed lsn file(.json)* String/Expression

Appears when you select the Polling mode checkbox.

Specify the name of the JSON file that stored the last processed LSN when polling. This file is stored on SLDB.

Default value: minLogSequenceNumber.json

Example: minLLSNTestDbEmployee.json
Process the response as bulk Checkbox Select this checkbox, to display the data in bulk within the content object in the output.

Default status: Deselected

Number of retries Integer/Expression

Specify the maximum number of attempts to be made to receive a response. The request is terminated if the attempts do not result in a response.

Default value: 3

Example: 5
Retry interval Integer

Specify the time interval between two successive retry requests. A retry happens only when the previous attempt resulted in an exception. The interval is in seconds

Default value: 5

Example: 3
Snap execution Dropdown list
Choose one of the three modes in which the Snap executes. Available options are:
  • Validate & Execute: Performs limited execution of the Snap and generates a data preview during pipeline validation. Subsequently, performs full execution of the Snap (unlimited records) during pipeline runtime.
  • Execute only: Performs full execution of the Snap during pipeline execution without generating preview data.
  • Disabled: Disables the Snap and all Snaps that are downstream from it.

Default value: Validate & Execute

Example: Execute only

Examples

Troubleshooting

No data in the output.

There are no transctions in the defined period.

Verify the specified time range or polling interval to ensure that it encompasses periods with transactions.

Examples