COF-C03 Question 54
Single answerParameter precedenceA Snowflake administrator is troubleshooting why a BI analyst's session times out after 15 minutes of inactivity, even though the company standard is 60 minutes. The administrator verifies the following settings for the SESSION_IDLE_TIMEOUT_MINS parameter:
- Account level: 60
- User ANALYST1: 45
- Warehouse BI_WH: 30
- The analyst connects using a role that has no parameter override
- After connecting, the analyst runs: ALTER SESSION SET SESSION_IDLE_TIMEOUT_MINS = 15;
What timeout value will apply to the analyst's current session?
- A
60 minutes, because account-level parameters apply unless a role override exists
- B
45 minutes, because user-level parameters override account-level and warehouse-level settings
- C
30 minutes, because warehouse-level parameters take precedence for all queries executed on that warehouse
- D
15 minutes, because a session-level setting overrides user-, warehouse-, and account-level settings for that session
Show answer and explanation
Correct answer: D
Explanation
Snowflake supports parameter settings at multiple levels, including account, user, session, and for some parameters, object scopes such as warehouse. The effective value is determined by precedence, with the most specific applicable scope winning. In this scenario, even though the account is set to 60, the user is set to 45, and the warehouse is set to 30, the explicit ALTER SESSION command changes the effective value for the current session to 15. This is a practical troubleshooting pattern on the SnowPro Core exam: determine not just where a parameter is set, but which scope is most specific and currently active. Refer to Snowflake documentation on parameters and parameter hierarchy/precedence, especially ALTER SESSION and parameter inheritance behavior.
- A. Incorrect.
Incorrect. Account-level parameters provide defaults, but they do not take precedence over more specific settings such as user-level or session-level values. The absence of a role-level override does not cause the account value to win over a session override.
- B. Incorrect.
Incorrect. User-level parameters do override account-level defaults in many cases, so 45 is more specific than 60. However, in this scenario the user explicitly changed the parameter at the session level after connecting, and the session-level value takes precedence for the active session.
- C. Incorrect.
Incorrect. This reflects a common misconception that warehouse settings control all execution behavior for sessions using that warehouse. Warehouse parameters can affect behavior for statements running on that warehouse, but they do not override a parameter explicitly set at the session level for the current session.
- D. Correct.
Correct. In Snowflake, parameter precedence is based on scope, with the most specific applicable setting taking effect. A value set with ALTER SESSION applies to the current session and overrides broader settings such as user, warehouse, and account values.