![]() ![]() ![]() To view the distribution style of a table, query the SVV_TABLE_INFO system catalog view. See Amazon Redshift Advisor recommendations.įor more information about DISTSTYLE AUTO, see Then Amazon Redshift might change the distribution style or key of your table in the future.įor example, Amazon Redshift might convert a table with a DISTSTYLE of AUTO(KEY) to AUTO(EVEN), or vice versa.įor more information about behavior when distribution keys are altered, including data redistribution and locks, If Amazon Redshift determines that a new distribution style or key will improve the performance of queries, In this case, Amazon Redshift makes no changes to the table. This clause only supports altering the size of a VARCHAR data type.Ī small table with DISTSTYLE ALL is converted to AUTO(ALL).Ī small table with DISTSTYLE EVEN is converted to AUTO(ALL).Ī small table with DISTSTYLE KEY is converted to AUTO(ALL).Ī large table with DISTSTYLE ALL is converted to AUTO(EVEN).Ī large table with DISTSTYLE EVEN is converted to AUTO(EVEN).Ī large table with DISTSTYLE KEY is converted to AUTO(KEY) and the DISTKEY is preserved. ALTER COLUMN column_name TYPEĪ clause that changes the size of a column defined as a VARCHAR data type. Table name beginning with '#' indicates a temporary table. You can't rename a permanent table to a name that begins with '#'. The maximum table name length is 127 bytes OWNER TO new_ownerĪ clause that changes the owner of the table (or view) to theĪ clause that renames a table (or view) to the value specified in CASCADE is an option for DROP CONSTRAINT. CASCADEĪ clause that removes the specified constraint and anything dependent on RESTRICT is an optionįor DROP CONSTRAINT. To reduce the time to run the ALTER TABLE command, you can combine some clauses ofĪmazon Redshift supports the following combinations of the ALTER TABLE clauses:įrom information_schema.table_constraints RESTRICTĪ clause that removes only the specified constraint. | DROP PARTITION ( partition_column= partition_value ) | ALTER DISTSTYLE KEY DISTKEY column_name | ALTER COLUMN column_name ENCODE encode_type. | ALTER COLUMN column_name ENCODE encode_type, | ALTER COLUMN column_name ENCODE new_encode_type | ALTER COLUMN column_name TYPE updated_varchar_data_type_size Table owner with the USAGE privilege on the schema ![]()
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