Max Partition Size

Definition

Asserts the maximum number of records that should be loaded from each file or table partition.

In-Depth Overview

Managing the volume of data in each partition is critical when dealing with partitioned datasets. This is especially pertinent when system limitations or data processing capabilities are considered, ensuring that no partition exceeds the system's ability to handle data efficiently.

The Max Partition Size rule is designed to set an upper limit on the number of records each partition can contain.

General Properties

Details

Name	Supported
Filter Allows the targeting of specific data based on conditions
Coverage Customization Allows adjusting the percentage of records that must meet the rule's conditions

Specific Properties

Specifies the maximum allowable record count for each data partition

Name	Description
Maximum partition size	The maximum number of records that can be loaded from each partition.

Anomaly Types

Type	Supported
Record Flag inconsistencies at the row level
Shape Flag inconsistencies in the overall patterns and distributions of a field

Example

Objective: Ensure that no partition of the LINEITEM table contains more than 10,000 records to prevent data processing bottlenecks.

Sample Data for Partition P3

Row Number	L_ITEM
1	Data
2	Data
...	...
10,050	Data

In the sample data above, the rule is violated because partition P3 contains 10,050 records, which exceeds the set maximum of 10,000 records.

FlowchartSQL

graph TD
A[Start] --> B[Retrieve Number of Records for Each Partition]
B --> C{Does Partition have <= 10,000 records?}
C -->|Yes| D[Move to Next Partition/End]
C -->|No| E[Mark as Anomalous]
E --> D

-- An illustrative SQL query demonstrating the rule applied to example dataset(s). 
select
    subset_name, -- or any column indicating the partition or subset
    count(*)
from lineitem 
group by subset_name
having count(*) > 10000;

Potential Violation Messages

Shape Anomaly

In LINEITEM, more than 10,000 records were loaded.

Last update: April 27, 2024