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· One min read
Jeffrey Aven

Snowflake allows roles to be assigned to other roles, so when a user is assigned to a role, they may inherit the ability to use countless other roles.

Challenge: recursively enumerate all roles for a given user

One solution would be to create a complex query on the “SNOWFLAKE"."ACCOUNT_USAGE"."GRANTS_TO_ROLES" object.

An easier solution is to use a stored procedure to recurse through grants for a given user and return an ARRAY of roles for that user.

This is a good programming exercise in tail call recursion (sort of) in JavaScript. Here is the code:

To call the stored proc, execute:

One drawback of stored procedures in Snowflake is that they can only have scalar or array return types and cannot be used directly in a SQL query, however you can use the table(result_scan(last_query_id())) trick to get around this, as shown below where we will pivot the ARRAY into a record set with the array elements as rows:

IMPORTANT

This query must be the next statement run immediately after the CALL statement and cannot be run again until you run another CALL statement.

More adventures with Snowflake soon!