System Variables

Opteryx exposes 23 system variables that a session can read. Use SHOW VARIABLES to list them, and SET to change the ones you are permitted to change.

Be Aware

Most system variables are not settable from SQL. A session runs at the USER tier, so only USER-owned variables are reachable by SET at all. Everything else is fixed by the server or stamped per session.

Note: This page lists the variables a session can see. An embedded build of opteryx-core may display additional variables that are internal to the hosted service and not part of the documented SQL surface.

Settable by any session

Variable	Type	Default
`like_selectivity_decay`	FLOAT64	env `LIKE_SELECTIVITY_DECAY`
`match_threshold`	FLOAT64	env `MATCH_THRESHOLD`
`trace`	BOOL	env `OPTERYX_TRACE`
`write_coalesce_rows`	INT64	env `WRITE_COALESCE_ROWS`

Not settable from SQL

Read-only from a session. Server-owned values are fixed when the server starts; session-identity values are stamped from the connection.

Variable	Type	Default
`array_agg_memory_budget_bytes`	INT64	`536870912`
`billing_account`	VARCHAR	per session
`build`	INT64	`3099`
`character_set_client`	VARCHAR	`utf8`
`cidr_agg_emit_budget_bytes`	INT64	`536870912`
`cidr_agg_state_budget_bytes`	INT64	`536870912`
`default_storage_engine`	VARCHAR	`rugo-parquet`
`external_user`	VARCHAR	per session
`job_retention_days`	INT64	`14`
`max_execution_time`	INT64	`1200`
`max_sql_length`	INT64	`256000`
`median_memory_budget_bytes`	INT64	`536870912`
`result_retention_days`	INT64	`7`
`sql_mode`	VARCHAR	`opteryx`
`sql_select_limit`	INT64	`1073741824`
`system_time_zone`	VARCHAR	`UTC`
`user_entitlements`	ARRAY	per session
`user_memberships`	ARRAY	per session
`version`	VARCHAR	from the build

Where defaults come from

env KEY — read from that environment variable when the server starts. The shipped fallback lives in the engine's configuration, not here: recording a value generated on one machine would describe that machine rather than the product.
detected from the host — derived at startup (CPU count, memory limits, platform).
per session — identity asserted by the connecting service, not configuration. See SHOW USER and SHOW GRANTS.