SnowConvert AI - Greenplum - CREATE TABLE¶

Description¶

This section explains features exclusive to Greenplum.

For more information, please refer to CREATE TABLE (https://techdocs.broadcom.com/us/en/vmware-tanzu/data-solutions/tanzu-greenplum/7/greenplum-database/ref_guide-sql_commands-CREATE_TABLE.html) the documentation.

Grammar Syntax¶

CREATE TABLE <table_name> ( 
  [ <column_name> <data_type> [ ENCODING ( <storage_directive> [, ...] ) ]
] )
[ DISTRIBUTED BY ( <column> [<opclass>] [, ... ] ) 
    | DISTRIBUTED RANDOMLY
    | DISTRIBUTED REPLICATED ]

ENCODING¶

The compression encoding for a column. In Snowflake, defining ENCODING is unnecessary because it automatically handles data compression, unlike Greenplum, which could set up the encoding manually. For this reason, the ENCODING statement is removed during migration.

ENCODING ( <storage_directive> [, ...] )

CREATE TABLE TABLE1 (
   COL1 integer ENCODING (compresstype = quicklz, blocksize = 65536)
);

CREATE TABLE TABLE1 (
   COL1 integer
)
COMMENT = '{ "origin": "sf_sc", "name": "snowconvert", "version": {  "major": 0,  "minor": 0,  "patch": "0" }, "attributes": {  "component": "greenplum",  "convertedOn": "03/26/2025",  "domain": "test" }}'
;

DISTRIBUTED BY¶

The DISTRIBUTED BY clause in Greenplum controls how table data is physically distributed across the system’s segments. Meanwhile, CLUSTER BY is a subset of columns in a table (or expressions on a table) that are explicitly designated to co-locate the data in the table in the same micro-partitions.

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

CREATE TABLE table1 (colum1 int, colum2 int, colum3 smallint, colum4 int )
DISTRIBUTED BY (colum1, colum2);

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" }}'
;

DISTRIBUTED RANDOMLY - REPLICATED¶

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

DISTRIBUTED RANDOMLY | DISTRIBUTED REPLICATED

CREATE TABLE table1 (colum1 int, colum2 int, colum3 smallint, colum4 int )
DISTRIBUTED RANDOMLY;

CREATE TABLE table1 (colum1 int, colum2 int, colum3 smallint, colum4 int )
COMMENT = '{ "origin": "sf_sc", "name": "snowconvert", "version": {  "major": 0,  "minor": 0,  "patch": "0" }, "attributes": {  "component": "greenplum",  "convertedOn": "03/26/2025",  "domain": "test" }}'
;

Related EWIs¶

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