I get the following error: 1064 (HY000): Getting syntax error. Detail message: Statement exceeds maximum length limit, please consider modify 'parse_tokens_limit' session variable. I set the global variable to a much higher number. Restarted BE/FE and still the same error persists.

@Rocky I get the following error: 1064 (HY000): Getting syntax error. Detail message: Statement exceeds maximum length limit, please consider modify 'parse_tokens_limit' session variable. I set the global variable to a much higher number. Restarted BE/FE and still the same error persists.

The error you're encountering is specifically triggered by the StarRocks SQL parser when it encounters a statement with a very large number of tokens (words, symbols, constants, etc.). While you've attempted to set it globally, there are a few reasons why it might still be failing. 1. Verify the Variable Value First, check if the variable change actually took effect in your current session. Global variables in StarRocks serve as the default for new sessions, but some clients or connection pools might persist old session settings. Run this in the same session where the error occurs:

sql
SHOW VARIABLES LIKE 'parse_tokens_limit';

If it still shows the default value (usually

3500000

), your

SET GLOBAL

command might not have applied to the active connection, or your client is overriding it. 2. Correct Way to Set the Variable

parse_tokens_limit

is a system variable, not a configuration file (

fe.conf

) parameter. Setting it in

fe.conf

and restarting will have no effect. You must set it via SQL. If you are using a very large SQL statement, try setting it at the session level immediately before running your query to ensure it applies:

sql
-- Increase to a much larger value, e.g., 10 million or more
SET parse_tokens_limit = 20000000; 

-- Then run your query
SELECT ...;

3. Check for Related Limits Even if you increase the token limit, extremely large SQL statements (like those with massive

IN

clauses or thousands of

OR

conditions) often hit secondary limits in the analyzer or the network layer: *

expr_children_limit

(FE Configuration): This limits the number of elements in a single expression (e.g., items inside

IN (...)

). The default is

10000

. If your query is large enough to hit the token limit, it is almost certainly hitting this too. This is an FE config, set it like this:

sql
    ADMIN SET FRONTEND CONFIG ("expr_children_limit" = "1000000");

*

max_allowed_packet

(Session Variable): This limits the total size (in bytes) of the SQL text sent from the client to the server. The default is

33554432

(32MB). If your SQL string is larger than 32MB, increase this:

sql
    SET GLOBAL max_allowed_packet = 1073741824; -- 1GB

4. Why "Restarting" didn't work In StarRocks,

SET GLOBAL

variables are persisted in the FE's internal metadata. Restarting the FE/BE is usually not necessary for these changes to take effect, but it also won't "fix" a variable that wasn't set correctly in the metadata. If you added

parse_tokens_limit

to

fe.conf

, the FE ignored it because it's not a valid boot-time config parameter. Recommended Troubleshooting Steps: 1. Check current session values:

SHOW VARIABLES LIKE 'parse_tokens_limit';

2. Apply at session level: Run

SET parse_tokens_limit = 20000000;

in your current window before the query. 3. Increase expression limit: Run

ADMIN SET FRONTEND CONFIG ("expr_children_limit" = "1000000");

. 4. Simplify if possible: If the query still fails, consider breaking it into smaller chunks, using a temporary table, or using a

JOIN

with a CTE instead of a massive

IN

list. References • administration/management/FE_configuration.md