ALTER SYSTEM statement

The ALTER SYSTEM statement is used to alter the entire datastore. It can be used to compact the system, or to set or drop a systemwide query timeout.

This statement is the only ALTER statement that does not have a corresponding DEFINE statement.

Statement syntax

ALTER SYSTEM 
    COMPACT |
    QUERY_TIMEOUT |
    DROP QUERY_TIMEOUT

QUERY_TIMEOUT clause

A query timeout can be set for the system as a whole. The minimum possible timeout is one millisecond, below which the value will be set as NONE.

ALTER SYSTEM QUERY_TIMEOUT 100ns;
INFO FOR ROOT.config;

{ QUERY_TIMEOUT: NONE }

Any value above 1ms will set the timeout, beyond which no query that takes any longer than this will succeed.

ALTER SYSTEM QUERY_TIMEOUT 1ms;
FOR $_ IN 0..1000 {
    FOR $_ IN 0..1000 {
        CREATE |person:1000|;
    }
};

-- 'The query was not executed because it exceeded the timeout: 1ms'

COMPACT clause

Compacts the entire datastore. To compact other resources, use ALTER NAMESPACE to compact the current namespace keyspace, ALTER DATABASE to compact the current database keyspace, or ALTER TABLE to compact a specific table keyspace.

The actual compaction used will depend on the datastore, such as RocksDB or SurrealKV.

This clause will not work with in-memory storage which has nothing persistent to compact, producing the following error:

'The storage layer does not support compaction requests.'

A successful compaction will return NONE.

ALTER SYSTEM COMPACT;
-- NONE