Condition Checks

Null, Unique, Zero tests.

These are three separate, simple monitor types grouped together because none of them takes a threshold or a pattern — the rule for what makes a row fail is fixed and built into the check itself. The only thing you configure is how many failures to tolerate.

Null

What it does

Checks that a column doesn't contain too many null (empty or missing) values. Applies to all data types.

When to use it

• Every row in a users table is required to have an email. A daily Null check on the email column with zero tolerance means any null value raises an incident.

• Phone numbers are known to be optional at signup, so some missing values are tolerated. A daily Null check on phone_number with 10% tolerance only alerts when more than 10% of rows are null.

What's configurable

• Schedule — fixed recurring, or Manual (requires Full Table Scan if Manual).

• Scan Method — Full Table Scan or Incremental Scan.

• Tolerance (optional) — how many, or what percentage of, null rows are allowed.

Worked example 1 — zero tolerance

• Asset: users table, column email

• Tolerance: not set

Resulting rule: "An incident will be created when any row fails."

Worked example 2 — with tolerance

• Asset: users table, column phone_number

• Tolerance: Percentage — 10%

Resulting rule: "An incident will be created when more than 10.0% of the scanned rows fail."

Unique

What it does

Checks that a column doesn't contain too many duplicate values. Applies to all data types.

When to use it

• order_id in an orders table is required to be unique. A daily Unique check with zero tolerance means any duplicate order ID raises an incident.

• Phone numbers may legitimately be shared across accounts — for example, family members — but widespread duplication is suspicious. A daily Unique check on phone_number with 10% tolerance allows for some sharing.

What's configurable

Same as Null: Schedule, Scan Method, and Tolerance (optional).

Worked example

• Asset: orders table, column order_id

• Tolerance: not set

Resulting rule: "An incident will be created when any row fails."

Zero

What it does

Checks that a numeric column doesn't contain too many zero values. Only applies to numeric column types.

When to use it

A unit_price column in a products table should never be 0, since a zero price usually signals a missing or mis-loaded value. A daily Zero check flags any row with a price of 0.

What's configurable

Same as Null and Unique: Schedule, Scan Method, and Tolerance (optional).

Worked example

• Asset: products table, column unit_price

• Tolerance: not set

Resulting rule: "An incident will be created when any row fails."

Notes

• Changing the schedule or scan method later is a destructive change (it creates a new monitor version). Adjusting only the tolerance value is not.

• These three checks have no threshold and no pattern or value set to configure — the only lever you have, beyond schedule and scan method, is tolerance.