Last updated: July 22, 2025

List of column level uniqueness data quality checks

This is a list of uniqueness column data quality checks supported by DQOps and a brief description of what data quality issued they detect.

column-level uniqueness checks

Counts the number or percent of duplicate or unique values in a column.

distinct count

This check counts distinct values and verifies if the distinct count is within an accepted range. It raises a data quality issue when the distinct count is below or above the accepted range.

Data quality check name	Friendly name	Check type	Description
`profile_distinct_count`	Verify that the count of distinct values is in the expected range	profiling	Verifies that the number of distinct values stays within an accepted range.
`daily_distinct_count`	Verify that the count of distinct values is in the expected range	monitoring	Verifies that the number of distinct values stays within an accepted range. Stores the most recent captured value for each day when the data quality check was evaluated.
`monthly_distinct_count`	Verify that the count of distinct values is in the expected range	monitoring	Verifies that the number of distinct values stays within an accepted range. Stores the most recent check result for each month when the data quality check was evaluated.
`daily_partition_distinct_count`	Verify that the count of distinct values is in the expected range	partitioned	Verifies that the number of distinct values stays within an accepted range. Stores a separate data quality check result for each daily partition.
`monthly_partition_distinct_count`	Verify that the count of distinct values is in the expected range	partitioned	Verifies that the number of distinct values stays within an accepted range. Stores a separate data quality check result for each monthly partition.

This check measures the percentage of distinct values in all non-null values. It verifies that the percentage of distinct values meets a minimum and maximum values. The default value of 100% distinct values ensures the column has no duplicate values.

Data quality check name	Friendly name	Check type	Description
`profile_distinct_percent`	The minimum ratio of distinct values to the count of non null values (detect duplicate values)	profiling	Verifies that the percentage of distinct values in a column does not fall below the minimum accepted percent.
`daily_distinct_percent`	The minimum ratio of distinct values to the count of non null values (detect duplicate values)	monitoring	Verifies that the percentage of distinct values in a column does not fall below the minimum accepted percent. Stores the most recent captured value for each day when the data quality check was evaluated.
`monthly_distinct_percent`	The minimum ratio of distinct values to the count of non null values (detect duplicate values)	monitoring	Verifies that the percentage of distinct values in a column does not fall below the minimum accepted percent. Stores the most recent check result for each month when the data quality check was evaluated.
`daily_partition_distinct_percent`	The minimum ratio of distinct values to the count of non null values (detect duplicate values)	partitioned	Verifies that the percentage of distinct values in a column does not fall below the minimum accepted percent. Stores a separate data quality check result for each daily partition.
`monthly_partition_distinct_percent`	The minimum ratio of distinct values to the count of non null values (detect duplicate values)	partitioned	Verifies that the percentage of distinct values in a column does not fall below the minimum accepted percent. Stores a separate data quality check result for each monthly partition.

duplicate count

This check counts duplicate values. It raises a data quality issue when the number of duplicates is above a minimum accepted value. The default configuration detects duplicate values by enforcing that the min_count of duplicates is zero.

Data quality check name	Friendly name	Check type	Description
`profile_duplicate_count`	Maximum count of duplicate values	profiling	Verifies that the number of duplicate values in a column does not exceed the maximum accepted count.
`daily_duplicate_count`	Maximum count of duplicate values	monitoring	Verifies that the number of duplicate values in a column does not exceed the maximum accepted count. Stores the most recent captured value for each day when the data quality check was evaluated.
`monthly_duplicate_count`	Maximum count of duplicate values	monitoring	Verifies that the number of duplicate values in a column does not exceed the maximum accepted count. Stores the most recent check result for each month when the data quality check was evaluated.
`daily_partition_duplicate_count`	Maximum count of duplicate values	partitioned	Verifies that the number of duplicate values in a column does not exceed the maximum accepted count. Stores a separate data quality check result for each daily partition.
`monthly_partition_duplicate_count`	Maximum count of duplicate values	partitioned	Verifies that the number of duplicate values in a column does not exceed the maximum accepted count. Stores a separate data quality check result for each monthly partition.

duplicate percent

This check measures the percentage of duplicate values in all non-null values. It raises a data quality issue when the percentage of duplicates is above an accepted threshold. The default threshold is 0% duplicate values.

Data quality check name	Friendly name	Check type	Description
`profile_duplicate_percent`	Maximum percentage of duplicate values	profiling	Verifies that the percentage of duplicate values in a column does not exceed the maximum accepted percentage.
`daily_duplicate_percent`	Maximum percentage of duplicate values	monitoring	Verifies that the percentage of duplicate values in a column does not exceed the maximum accepted percentage. Stores the most recent captured value for each day when the data quality check was evaluated.
`monthly_duplicate_percent`	Maximum percentage of duplicate values	monitoring	Verifies that the percentage of duplicate values in a column does not exceed the maximum accepted percentage. Stores the most recent check result for each month when the data quality check was evaluated.
`daily_partition_duplicate_percent`	Maximum percentage of duplicate values	partitioned	Verifies that the percent of duplicate values in a column does not exceed the maximum accepted percent. Stores a separate data quality check result for each daily partition.
`monthly_partition_duplicate_percent`	Maximum percentage of duplicate values	partitioned	Verifies that the percent of duplicate values in a column does not exceed the maximum accepted percent. Stores a separate data quality check result for each monthly partition.

distinct count anomaly

This check monitors the count of distinct values and detects anomalies in the changes of the distinct count. It monitors a 90-day time window. The check is configured by setting a desired percentage of anomalies to identify as data quality issues.

Data quality check name	Friendly name	Check type	Description
`profile_distinct_count_anomaly`	Abnormal change in the number of distinct values. Measured as a percentile of anomalous measures.	profiling	Verifies that the distinct count in a monitored column is within a two-tailed percentile from measurements made during the last 90 days.
`daily_distinct_count_anomaly`	Abnormal change in the number of distinct values. Measured as a percentile of anomalous measures.	monitoring	Verifies that the distinct count in a monitored column is within a two-tailed percentile from measurements made during the last 90 days.
`daily_partition_distinct_count_anomaly`	Abnormal change in the number of distinct values. Measured as a percentile of anomalous measures.	partitioned	Verifies that the distinct count in a monitored column is within a two-tailed percentile from measurements made during the last 90 days.

distinct percent anomaly

This check monitors the percentage of distinct values and detects anomalies in the changes in this percentage. It monitors a 90-day time window. The check is configured by setting a desired percentage of anomalies to identify as data quality issues.

Data quality check name	Friendly name	Check type	Description
`profile_distinct_percent_anomaly`	Abnormal change in the percentage of distinct values. Measured as a percentile of anomalous measures.	profiling	Verifies that the distinct percent in a monitored column is within a two-tailed percentile from measurements made during the last 90 days.
`daily_distinct_percent_anomaly`	Abnormal change in the percentage of distinct values. Measured as a percentile of anomalous measures.	monitoring	Verifies that the distinct percent in a monitored column is within a two-tailed percentile from measurements made during the last 90 days.
`daily_partition_distinct_percent_anomaly`	Abnormal change in the percentage of distinct values. Measured as a percentile of anomalous measures.	partitioned	Verifies that the distinct percent in a monitored column is within a two-tailed percentile from measurements made during the last 90 days.

distinct count change

This check monitors the count of distinct values and compares it to the last known value. It raises a data quality issue when the change exceeds an accepted threshold.

Data quality check name	Friendly name	Check type	Description
`profile_distinct_count_change`	Maximum relative change in the count of distinct values since the last known value	profiling	Verifies that the distinct count in a monitored column has changed by a fixed rate since the last readout.
`daily_distinct_count_change`	Maximum relative change in the count of distinct values since the last known value	monitoring	Verifies that the distinct count in a monitored column has changed by a fixed rate since the last readout.
`monthly_distinct_count_change`	Maximum relative change in the count of distinct values since the last known value	monitoring	Verifies that the distinct count in a monitored column has changed by a fixed rate since the last readout.
`daily_partition_distinct_count_change`	Maximum relative change in the count of distinct values since the last known value	partitioned	Verifies that the distinct count in a monitored column has changed by a fixed rate since the last readout.
`monthly_partition_distinct_count_change`	Maximum relative change in the count of distinct values since the last known value	partitioned	Verifies that the distinct count in a monitored column has changed by a fixed rate since the last readout.

distinct count change 1 day

This check monitors the count of distinct values and compares it to the measure from the previous day. It raises a data quality issue when the change exceeds an accepted threshold.

Data quality check name	Friendly name	Check type	Description
`profile_distinct_count_change_1_day`	Maximum relative change in the count of distinct values vs 1 day ago	profiling	Verifies that the distinct count in a monitored column has changed by a fixed rate since the last readout from yesterday.
`daily_distinct_count_change_1_day`	Maximum relative change in the count of distinct values vs 1 day ago	monitoring	Verifies that the distinct count in a monitored column has changed by a fixed rate since the last readout from yesterday.
`daily_partition_distinct_count_change_1_day`	Maximum relative change in the count of distinct values vs 1 day ago	partitioned	Verifies that the distinct count in a monitored column has changed by a fixed rate since the last readout from yesterday.

distinct count change 7 days

This check monitors the count of distinct values and compares it to the measure seven days ago to overcome the weekly seasonability impact. It raises a data quality issue when the change exceeds an accepted threshold.

Data quality check name	Friendly name	Check type	Description
`profile_distinct_count_change_7_days`	Maximum relative change in the count of distinct values vs 7 days ago	profiling	Verifies that the distinct count in a monitored column has changed by a fixed rate since the last readout from last week.
`daily_distinct_count_change_7_days`	Maximum relative change in the count of distinct values vs 7 days ago	monitoring	Verifies that the distinct count in a monitored column has changed by a fixed rate since the last readout from last week.
`daily_partition_distinct_count_change_7_days`	Maximum relative change in the count of distinct values vs 7 days ago	partitioned	Verifies that the distinct count in a monitored column has changed by a fixed rate since the last readout from the last week.

distinct count change 30 days

This check monitors the count of distinct values and compares it to the measure thirty days ago to overcome the monthly seasonability impact. It raises a data quality issue when the change exceeds an accepted threshold.

Data quality check name	Friendly name	Check type	Description
`profile_distinct_count_change_30_days`	Maximum relative change in the count of distinct values vs 30 days ago	profiling	Verifies that the distinct count in a monitored column has changed by a fixed rate since the last readout from last month.
`daily_distinct_count_change_30_days`	Maximum relative change in the count of distinct values vs 30 days ago	monitoring	Verifies that the distinct count in a monitored column has changed by a fixed rate since the last readout from last month.
`daily_partition_distinct_count_change_30_days`	Maximum relative change in the count of distinct values vs 30 days ago	partitioned	Verifies that the distinct count in a monitored column has changed by a fixed rate since the last readout from the last month.

distinct percent change

This check monitors the percentage of distinct values and compares it to the last known value. It raises a data quality issue when the change exceeds an accepted threshold.

Data quality check name	Friendly name	Check type	Description
`profile_distinct_percent_change`	Maximum relative change in the percentage of distinct values since the last known value	profiling	Verifies that the distinct percent in a monitored column has changed by a fixed rate since the last readout.
`daily_distinct_percent_change`	Maximum relative change in the percentage of distinct values since the last known value	monitoring	Verifies that the distinct percent in a monitored column has changed by a fixed rate since the last readout.
`monthly_distinct_percent_change`	Maximum relative change in the percentage of distinct values since the last known value	monitoring	Verifies that the distinct percent in a monitored column has changed by a fixed rate since the last readout.
`daily_partition_distinct_percent_change`	Maximum relative change in the percentage of distinct values since the last known value	partitioned	Verifies that the distinct percent in a monitored column has changed by a fixed rate since the last readout.
`monthly_partition_distinct_percent_change`	Maximum relative change in the percentage of distinct values since the last known value	partitioned	Verifies that the distinct percent in a monitored column has changed by a fixed rate since the last readout.

distinct percent change 1 day

This check monitors the percentage of distinct values and compares it to the measure from the previous day. It raises a data quality issue when the change exceeds an accepted threshold.

Data quality check name	Friendly name	Check type	Description
`profile_distinct_percent_change_1_day`	Maximum relative change in the percentage of distinct values vs 1 day ago	profiling	Verifies that the distinct percent in a monitored column has changed by a fixed rate since the last readout from yesterday.
`daily_distinct_percent_change_1_day`	Maximum relative change in the percentage of distinct values vs 1 day ago	monitoring	Verifies that the distinct percent in a monitored column has changed by a fixed rate since the last readout from yesterday.
`daily_partition_distinct_percent_change_1_day`	Maximum relative change in the percentage of distinct values vs 1 day ago	partitioned	Verifies that the distinct percent in a monitored column has changed by a fixed rate since the last readout from yesterday.

distinct percent change 7 days

This check monitors the percentage of distinct values and compares it to the measure seven days ago to overcome the weekly seasonability impact. It raises a data quality issue when the change exceeds an accepted threshold.

Data quality check name	Friendly name	Check type	Description
`profile_distinct_percent_change_7_days`	Maximum relative change in the percentage of distinct values vs 7 days sago	profiling	Verifies that the distinct percent in a monitored column has changed by a fixed rate since the last readout from last week.
`daily_distinct_percent_change_7_days`	Maximum relative change in the percentage of distinct values vs 7 days sago	monitoring	Verifies that the distinct percent in a monitored column has changed by a fixed rate since the last readout from last week.
`daily_partition_distinct_percent_change_7_days`	Maximum relative change in the percentage of distinct values vs 7 days sago	partitioned	Verifies that the distinct percent in a monitored column has changed by a fixed rate since the last readout from the last week.

distinct percent change 30 days

This check monitors the percentage of distinct values and compares it to the measure thirty days ago to overcome the monthly seasonability impact. It raises a data quality issue when the change exceeds an accepted threshold.

Data quality check name	Friendly name	Check type	Description
`profile_distinct_percent_change_30_days`	Maximum relative change in the percentage of distinct values vs 30 days ago	profiling	Verifies that the distinct percent in a monitored column has changed by a fixed rate since the last readout from last month.
`daily_distinct_percent_change_30_days`	Maximum relative change in the percentage of distinct values vs 30 days ago	monitoring	Verifies that the distinct percent in a monitored column has changed by a fixed rate since the last readout from last month.
`daily_partition_distinct_percent_change_30_days`	Maximum relative change in the percentage of distinct values vs 30 days ago	partitioned	Verifies that the distinct percent in a monitored column has changed by a fixed rate since the last readout from the last month.