The SET command sets SQL engine parameters for the current session. Parameters take effect only within the current session and revert to their default values when the session ends.
Syntax
SET <parameter_name> = <value>
⚠️ Note: SET affects only the current session and does not impact other users or future sessions. To persistently configure object properties, use SET PROPERTIES.
Session Parameters
Parameter
Values
Default
Description
query_tag
string
none
Tags queries with a label that can be filtered in job history
schedule_job_queue_priority
0–9
0
Job priority; higher values mean higher priority
cz.sql.group.by.having.use.alias.first
true/false
false
Whether GROUP BY / HAVING prefers column aliases
cz.sql.double.quoted.identifiers
true/false
false
Whether double quotes act as delimited identifiers (when enabled, double quotes no longer represent strings)
cz.sql.cast.mode
tolerant/strict
tolerant
CAST conversion mode; in strict mode, conversion failures throw an error
cz.optimizer.enable.mv.rewrite
true/false
false
Whether to enable Materialized View query rewriting
cz.sql.string.literal.escape.mode
backslash/quote/quote_backslash
backslash
String escape character mode
cz.sql.arithmetic.mode
tolerant/strict
tolerant
Whether arithmetic errors throw an exception
cz.sql.timezone
timezone name
none
Sets the SQL session timezone, e.g. Asia/Shanghai or UTC
cz.sql.remote.udf.lookup.policy
builtin_first/udf_first/schema_only
schema_only
Resolution priority between UDFs and built-in functions
cz.sql.type.conversion
hive
none
Enables Hive-compatible type conversion rules
cz.sql.function.from.unixtime.trim.to.second
false/true
false
Truncates FROM_UNIXTIME precision to seconds (Hive compatibility)
cz.sql.time.parser.strict.mode
false/true
false
Strict time parsing mode; throws an error instead of returning NULL when format does not match
cz.sql.cast.string.to.integer.allow.truncate
false/true
false
Allows truncating decimal digits when casting string to integer (Hive compatibility)
Specifies the target engine for function compatibility (used with translation.mode)
Examples
-- Set timezone
SET cz.sql.timezone = 'Asia/Shanghai';
-- Set query tag
SET query_tag = 'etl_job';
-- Enable strict CAST mode
SET cz.sql.cast.mode = strict;
-- Set job priority
SET schedule_job_queue_priority = 5;
Once set, all query jobs in the session are tagged with this label, which you can filter in job history:
SET query_tag = 'aa';
SELECT 1;
-- Filter in information_schema
SELECT * FROM information_schema.job_history WHERE query_tag = 'aa';
-- Filter in SHOW JOBS
SHOW JOBS WHERE query_tag = 'aa' LIMIT 100;
cz.sql.double.quoted.identifiers
When enabled, double quotes act as delimited identifiers and no longer represent strings:
SET cz.sql.double.quoted.identifiers = true;
-- "column_name" is now an identifier, not a string
cz.sql.cast.mode
-- strict mode: conversion failure throws an error
SET cz.sql.cast.mode = strict;
SELECT CAST('abc' AS INT); -- error
-- tolerant mode (default): conversion failure returns NULL
SET cz.sql.cast.mode = tolerant;
SELECT CAST('abc' AS INT); -- NULL
cz.sql.arithmetic.mode
-- tolerant mode (default): division by zero returns NULL
SELECT 2/0; -- NULL
-- strict mode: division by zero throws an error
SET cz.sql.arithmetic.mode = strict;
SELECT 2/0; -- error
cz.sql.timezone
SET cz.sql.timezone = 'Asia/Shanghai';
SELECT NOW(); -- returns time in Asia/Shanghai
SET cz.sql.timezone = 'UTC';
SELECT NOW(); -- returns UTC time
cz.sql.string.literal.escape.mode
-- Default backslash mode
SELECT 'Hello \n World!'; -- newline
-- quote mode: use two single quotes to represent one single quote
SET cz.sql.string.literal.escape.mode = QUOTE;
SELECT 'It''s a beautiful day'; -- It's a beautiful day
-- quote_backslash mode: supports both escape styles simultaneously
SET cz.sql.string.literal.escape.mode = quote_backslash;
cz.sql.translation.mode (preview feature)
Automatically translates the specified SQL dialect into native Lakehouse syntax:
SET cz.sql.translation.mode = doris;
SELECT DATE_ADD(CURRENT_TIMESTAMP(), INTERVAL 1 HOUR);
-- Used with compatible.target
SET cz.sql.compatible.target = mysql;
SELECT DATE_FORMAT(CURRENT_DATE(), '%x-%v %a %W');
cz.sql.remote.udf.lookup.policy
-- Default schema_only: UDFs must be referenced with a schema prefix
SELECT public.my_func();
-- builtin_first: built-in functions take priority
SET cz.sql.remote.udf.lookup.policy = builtin_first;
SELECT my_func();
-- udf_first: UDFs take priority
SET cz.sql.remote.udf.lookup.policy = udf_first;
SELECT my_func();
schedule_job_queue_priority
-- Set high priority (0–9, higher value = higher priority)
SET schedule_job_queue_priority = 8;
SELECT * FROM large_table;
