From e2e57d36fb9728db20fa64ed1f97058cccddb401 Mon Sep 17 00:00:00 2001
From: Melody Ruch <396921921@qq.com>
Date: Sun, 20 Sep 2026 19:11:10 +0800
Subject: [PATCH] fix(sqlserver): merge composite foreign keys in exported ddl

---
 crates/dbx-core/src/schema/mod.rs | 50 +++++++++++++++++++++++++++----
 1 file changed, 45 insertions(+), 5 deletions(-)

diff --git a/crates/dbx-core/src/schema/mod.rs b/crates/dbx-core/src/schema/mod.rs
index 87060045c5..407ce04a1a 100644
--- a/crates/dbx-core/src/schema/mod.rs
+++ b/crates/dbx-core/src/schema/mod.rs
@@ -11819,6 +11819,41 @@ mod ddl_tests {
         assert!(ddl.contains("[FIDS] int IDENTITY(1,1) NOT NULL"), "ddl: {ddl}");
     }
 
+    #[test]
+    fn sqlserver_table_ddl_groups_composite_foreign_key_columns() {
+        let fk = |name: &str, column: &str, ref_table: &str, ref_column: &str| db::ForeignKeyInfo {
+            name: name.to_string(),
+            column: column.to_string(),
+            ref_schema: Some("dbo".to_string()),
+            ref_table: ref_table.to_string(),
+            ref_column: ref_column.to_string(),
+            on_update: None,
+            on_delete: None,
+        };
+        let fkeys = [
+            fk("FK_TRIGGERS_JOB", "sched_name", "JOB_DETAILS", "sched_name"),
+            fk("FK_TRIGGERS_JOB", "job_name", "JOB_DETAILS", "job_name"),
+            fk("FK_TRIGGERS_JOB", "job_group", "JOB_DETAILS", "job_group"),
+            fk("FK_TRIGGERS_CAL", "calendar_name", "CALENDARS", "calendar_name"),
+        ];
+
+        let ddl = render_sqlserver_table_ddl("dbo", "TRIGGERS", &[column("sched_name", "nvarchar")], &[], &fkeys, None);
+
+        assert!(
+            ddl.contains(
+                "CONSTRAINT [FK_TRIGGERS_JOB] FOREIGN KEY ([sched_name], [job_name], [job_group]) REFERENCES [JOB_DETAILS]([sched_name], [job_name], [job_group])"
+            ),
+            "ddl: {ddl}"
+        );
+        assert_eq!(ddl.matches("CONSTRAINT [FK_TRIGGERS_JOB]").count(), 1, "ddl: {ddl}");
+        assert!(
+            ddl.contains(
+                "CONSTRAINT [FK_TRIGGERS_CAL] FOREIGN KEY ([calendar_name]) REFERENCES [CALENDARS]([calendar_name])"
+            ),
+            "ddl: {ddl}"
+        );
+    }
+
     #[test]
     fn opengauss_table_ddl_uses_native_tabledef_function() {
         assert_eq!(
@@ -13498,13 +13533,18 @@ pub fn render_sqlserver_table_ddl(
             pks.iter().map(|k| sqlserver_ident(k)).collect::<Vec<_>>().join(", ")
         ));
     }
-    for fk in fkeys {
+    for fk_group in group_foreign_keys_by_name(fkeys) {
+        let Some(first_fk) = fk_group.first() else {
+            continue;
+        };
+        let columns = fk_group.iter().map(|fk| sqlserver_ident(&fk.column)).collect::<Vec<_>>().join(", ");
+        let ref_columns = fk_group.iter().map(|fk| sqlserver_ident(&fk.ref_column)).collect::<Vec<_>>().join(", ");
         ddl.push_str(&format!(
             ",\n  CONSTRAINT {} FOREIGN KEY ({}) REFERENCES {}({})",
-            sqlserver_ident(&fk.name),
-            sqlserver_ident(&fk.column),
-            sqlserver_ident(&fk.ref_table),
-            sqlserver_ident(&fk.ref_column)
+            sqlserver_ident(&first_fk.name),
+            columns,
+            sqlserver_ident(&first_fk.ref_table),
+            ref_columns
         ));
     }
     ddl.push_str("\n);\n");