From 0d81400bb41e8aefd392c306e1c5ae298618fcff Mon Sep 17 00:00:00 2001
From: dennis zhuang <killme2008@gmail.com>
Date: Tue, 3 Jun 2025 10:32:19 +0800
Subject: [PATCH] feat: supports select @@session.time_zone (#6212)

---
 src/servers/src/mysql/federated.rs | 2 +-
 tests-integration/tests/sql.rs     | 6 ++++++
 2 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/src/servers/src/mysql/federated.rs b/src/servers/src/mysql/federated.rs
index b1ceff311d..fccca58b2a 100644
--- a/src/servers/src/mysql/federated.rs
+++ b/src/servers/src/mysql/federated.rs
@@ -183,7 +183,7 @@ fn select_variable(query: &str, query_context: QueryContextRef) -> Option<Output
 
         // get value of variables from known sources or fallback to defaults
         let value = match var_as[0] {
-            "time_zone" => query_context.timezone().to_string(),
+            "session.time_zone" | "time_zone" => query_context.timezone().to_string(),
             "system_time_zone" => system_timezone_name(),
             _ => VAR_VALUES
                 .get(var_as[0])
diff --git a/tests-integration/tests/sql.rs b/tests-integration/tests/sql.rs
index c5a1b441d3..8cc9f80dd5 100644
--- a/tests-integration/tests/sql.rs
+++ b/tests-integration/tests/sql.rs
@@ -339,6 +339,8 @@ pub async fn test_mysql_timezone(store_type: StorageType) {
 
     let timezone = conn.fetch_all("SELECT @@time_zone").await.unwrap();
     assert_eq!(timezone[0].get::<String, usize>(0), "Asia/Shanghai");
+    let timezone = conn.fetch_all("SELECT @@session.time_zone").await.unwrap();
+    assert_eq!(timezone[0].get::<String, usize>(0), "Asia/Shanghai");
     let timezone = conn.fetch_all("SELECT @@system_time_zone").await.unwrap();
     assert_eq!(timezone[0].get::<String, usize>(0), "UTC");
     let _ = conn.execute("SET time_zone = 'UTC'").await.unwrap();
@@ -367,6 +369,8 @@ pub async fn test_mysql_timezone(store_type: StorageType) {
     let _ = conn.execute("SET time_zone = '+08:00'").await.unwrap();
     let timezone = conn.fetch_all("SELECT @@time_zone").await.unwrap();
     assert_eq!(timezone[0].get::<String, usize>(0), "+08:00");
+    let timezone = conn.fetch_all("SELECT @@session.time_zone").await.unwrap();
+    assert_eq!(timezone[0].get::<String, usize>(0), "+08:00");
 
     let rows2 = conn.fetch_all("select ts from demo").await.unwrap();
     // we use Utc here for format only
@@ -391,6 +395,8 @@ pub async fn test_mysql_timezone(store_type: StorageType) {
     );
     let timezone = conn.fetch_all("SELECT @@time_zone").await.unwrap();
     assert_eq!(timezone[0].get::<String, usize>(0), "-07:00");
+    let timezone = conn.fetch_all("SELECT @@session.time_zone").await.unwrap();
+    assert_eq!(timezone[0].get::<String, usize>(0), "-07:00");
 
     let _ = fe_mysql_server.shutdown().await;
     guard.remove_all().await;