Code Conversion - Greenplum Functional Differences

Note

Conversion Scope

For Greenplum, the assessment and translation capabilities primarily focus on TABLES and VIEWS. While other types of ANSI-standard statements are recognized, they are not yet fully supported for conversion. The tool may identify them, but will not perform a complete translation for these unsupported code units.

SSC-FDM-GP0001

The performance of the CLUSTER BY may vary compared to the performance of Distributed By

Description

The DISTRIBUTED BY in Greenplum is analogous to CLUSTER BY in Snowflake. However, performance implications may vary due to architectural differences between Greenplum and Snowflake.

  • DISTRIBUTED BY controls the physical distribution of data across the nodes (segments) in Greenplum’s MPP architecture..
  • CLUSTER BY in Snowflake organizes data into blocks based on designated columns, aiding in filtering and aggregation tasks.

Understanding these mechanisms is crucial for optimizing performance in each respective platform.

Code Example

Input Code:
Redshift
 CREATE TABLE table1 (colum1 int, colum2 int, colum3 smallint, colum4 int )
DISTRIBUTED BY (colum1, colum2);
Generated Code:
Snowflake
 CREATE TABLE table1 (colum1 int, colum2 int, colum3 smallint, colum4 int )
--** SSC-FDM-GP0001 - THE PERFORMANCE OF THE CLUSTER BY MAY VARY COMPARED TO THE PERFORMANCE OF DISTRIBUTED BY **
CLUSTER BY (colum1, colum2)
COMMENT = '{ "origin": "sf_sc", "name": "snowconvert", "version": {  "major": 0,  "minor": 0,  "patch": "0" }, "attributes": {  "component": "greenplum",  "convertedOn": "03/26/2025",  "domain": "test" }}'
;

Best Practices