Create an Is Replica Of Check

Deprecated: use Data Diff instead

The Is Replica Of rule is no longer maintained. Data Diff replaces it with the same row-by-row comparison plus change-type filtering. This page is kept as a reference for checks that already exist; new checks should use Data Diff.

Step-by-step tutorial for creating an Is Replica Of check. For new checks, use Data Diff instead: it takes the same configuration and is the maintained rule. For what each property means and how the rule evaluates the data, see the How It Works page.

Permission Required

You need the Author team permission on the datastore to create an Active check, or Drafter to create it as a Draft. See the Permissions page for the full matrix.

Show me how

The app can walk you through this. Click Show me how in the check creation form's header, or press H while it is open, and the Add a Check walkthrough highlights each step while you fill in the real form.

Field reference

The Authored Check Details form is organized in the sections below. Fill them in as you follow the Steps.

Target

Field	Type	Description
Associate with a Check Template	Toggle	Links the check to a Check Template. Enabling it replaces the Rule Type dropdown with a Template dropdown where you pick an existing template, which then controls the check's properties. When off, you configure everything on this form.
Rule Type	Option	The validation logic to apply. Select Is Replica Of for this check. Shown only while Associate with a Check Template is off.
Table / File	Option	The target container compared against the reference. Locked after the check is saved.
Fields	Option	The fields compared between the two sides, read on both the target and the reference container.
Filter Clause	Text	A SQL `WHERE` expression that limits the rows the check evaluates. Rows outside the filter are ignored entirely.
Custom Anomaly Description	Toggle	Has no effect on this rule. The option replaces the message on Record Anomalies, and Is Replica Of emits a Shape Anomaly only.

Properties

Field	Required	Type	Description
Row Identifiers		Option	The field, or combination of fields, used to pair each target row with its reference row. Without identifiers the check reports a set-level difference and cannot classify rows.
Passthrough Fields		Option	Extra fields shown alongside the compared ones for context. They are displayed but never compared.
Datastore		Option	The datastore holding the reference container. Leave it empty to use the target's own datastore.
Container		Option	The reference container compared against the target.
Filter Clause		SQL	A SQL `WHERE` expression that scopes the reference container before the comparison. Accepts Check Variables.
Numeric		Toggle	Enables a tolerance for numeric fields and displays Comparison and Threshold.
Comparison	When Numeric is enabled	Option	Determines how the tolerance is calculated. Absolute Value uses a fixed threshold. Percentage Value calculates the threshold as a percentage of the larger compared value.
Threshold	When Numeric is enabled	Number or Percentage	The maximum difference allowed between numeric values. The field is labeled Percentage Threshold when Percentage Value is selected.
Duration		Toggle	Enables a tolerance for date and timestamp fields and displays Unit and Value.
Unit	When Duration is enabled	Option	The unit used for the tolerance: Millis, Seconds, or Days.
Value	When Duration is enabled	Number	The maximum time difference allowed between date or timestamp values, expressed in the selected Unit.
String		Toggle	Enables string comparison options and displays Ignore Whitespace.
Ignore Whitespace		Toggle	Removes leading and trailing whitespace and treats consecutive internal whitespace as a single space before comparing string values. The comparison remains case-sensitive.

Ownership

Field	Required	Type	Description
Owner		Option	The user responsible for the check. Already filled in with the check creator.
Anomaly Assignee		Option	The user automatically assigned to anomalies the check produces.

Metadata

Field	Type	Description
Description	Text	A plain-language description of what the check enforces. Supports Markdown formatting: click the field to open the Markdown editor. Click the Apply suggested description button for a suggestion based on the rule type.
Tags	Option	Tags applied to the check for filtering and organization.
Additional Metadata	Key-value	Custom key-value pairs, typically links to catalog entries, tickets, or governance records.

No Pass Criteria section

Is Replica Of does not use coverage, so the form shows no Coverage slider.

Let AgentQ fill in the form

When AgentQ is configured for your deployment, the Check Assistant panel in the check form can author the check for you: describe the rule in plain language (for example, "compare the orders table against its replica") and it proposes a configuration you can apply to the form. Review the filled-in fields, then Validate and Save as usual.

Steps

Each field is described in the Field reference above.

Step 1: Select the source datastore from the left menu, then click the Checks tab.

Step 2: Click Add in the top-right corner and select Check from the dropdown. The Authored Check Details form opens.

Step 3: Select Is Replica Of in the Rule Type dropdown.

Step 4: Fill in the remaining Target fields: the target table or file, the Fields to compare, and, optionally, a Filter Clause.

Step 5: Under Properties, set the Row Identifiers that pair the two sides and add any Passthrough Fields for context.

Step 6: Select the reference Container, the only required property. Fill in the reference Datastore when the container lives outside the target's datastore, add a reference Filter Clause to scope it, and set the Comparators when small differences should be tolerated.

Step 7: Fill in the Ownership and Metadata sections. Only the Description is required.

Step 8: Click Validate to test the rule against the selected data without saving it. A success message confirms the rule can run on that data. If validation fails, see Troubleshooting.

Step 9: Click Save. A success message confirms that the check was created.