ClickHouse/docs/en/sql-reference/statements/alter/quota.md

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46	QUOTA

ALTER QUOTA

Changes quotas.

Syntax:

ALTER QUOTA [IF EXISTS] name [ON CLUSTER cluster_name]
    [RENAME TO new_name]
    [KEYED BY {user_name | ip_address | client_key | client_key,user_name | client_key,ip_address} | NOT KEYED]
    [FOR [RANDOMIZED] INTERVAL number {second | minute | hour | day | week | month | quarter | year}
        {MAX { {queries | query_selects | query_inserts | errors | result_rows | result_bytes | read_rows | read_bytes | execution_time} = number } [,...] |
        NO LIMITS | TRACKING ONLY} [,...]]
    [TO {role [,...] | ALL | ALL EXCEPT role [,...]}]

Keys user_name, ip_address, client_key, client_key, user_name and client_key, ip_address correspond to the fields in the system.quotas table.

Parameters queries, query_selects, 'query_inserts', errors, result_rows, result_bytes, read_rows, read_bytes, execution_time` correspond to the fields in the system.quotas_usage table.

ON CLUSTER clause allows creating quotas on a cluster, see Distributed DDL.

Examples

Limit the maximum number of queries for the current user with 123 queries in 15 months constraint:

ALTER QUOTA IF EXISTS qA FOR INTERVAL 15 month MAX queries = 123 TO CURRENT_USER;

For the default user limit the maximum execution time with half a second in 30 minutes, and limit the maximum number of queries with 321 and the maximum number of errors with 10 in 5 quaters:

ALTER QUOTA IF EXISTS qB FOR INTERVAL 30 minute MAX execution_time = 0.5, FOR INTERVAL 5 quarter MAX queries = 321, errors = 10 TO default;