Greenplum

Translation from Greenplum to Snowflake

Description

This section explains features exclusive to Greenplum.

For more information, please refer to CREATE MATERIALIZE VIEW the documentation.

Grammar Syntax

CREATE MATERIALIZED VIEW <table_name>
    AS <query>
    [DISTRIBUTED {| BY <column> [<opclass>], [ ... ] | RANDOMLY | REPLICATED }]

DISTRIBUTED BY

This syntax is translated to its most equivalent form in Snowflake.

The DISTRIBUTED BY clause in Greenplum controls how data is physically distributed across the system's segments. Meanwhile, CLUSTER BY is a subset of columns in a dynamic table (or expressions on a dynamic table) explicitly designated to co-locate the data in the table in the same micro-partitions. While they operate at different architectural levels, they aim to improve query performance by distributing data efficiently.

Grammar Syntax

DISTRIBUTED BY ( <column> [<opclass>] [, ... ] )

Sample Source

Input Code:

Greenplum

IN -> Greenplum_01.sql

CREATE MATERIALIZED VIEW product_summary AS
SELECT
    category,
    COUNT(*) AS total_products,
    MAX(price) AS max_price
FROM products
GROUP BY category
DISTRIBUTED BY (category);

Output Code:

Snowflake

OUT -> Greenplum_01.sql

CREATE OR REPLACE DYNAMIC TABLE product_summary
--** SSC-FDM-0031 - DYNAMIC TABLE REQUIRED PARAMETERS SET BY DEFAULT **
TARGET_LAG='1 day'
WAREHOUSE=UPDATE_DUMMY_WAREHOUSE
--** SSC-FDM-GP0001 - THE PERFORMANCE OF THE CLUSTER BY MAY VARY COMPARED TO THE PERFORMANCE OF DISTRIBUTED BY **
CLUSTER BY (category)
COMMENT = '{ "origin": "sf_sc", "name": "snowconvert", "version": {  "major": 0,  "minor": 0,  "patch": "0" }, "attributes": {  "component": "greenplum",  "convertedOn": "04/24/2025",  "domain": "test" }}'
AS
    SELECT
    category,
    COUNT(*) AS total_products,
    MAX(price) AS max_price
FROM
    products
    GROUP BY category;

DISTRIBUTED RANDOMLY - REPLICATED

This syntax is not needed in Snowflake.

The DISTRIBUTED REPLICATED or DISTRIBUTED RANDOMLY clause in Greenplum controls how data is physically distributed across the system's segments. As Snowflake automatically handles data storage, these options will be removed in the migration.

Related EWIs

1. SSC-FDM-GP0001: The performance of the CLUSTER BY may vary compared to the performance of Distributed By.