From 6fe41de481f0b1a966a3a61531cb3770b10dfc17 Mon Sep 17 00:00:00 2001
From: saravanakumardb1 <saravanakumardb1@users.noreply.github.com>
Date: Mon, 2 Mar 2026 01:50:09 -0800
Subject: [PATCH] fix(datastore):  SQL now emits ARRAY_CONTAINS OR CONTAINS for
 array+string support

---
 packages/datastore/src/__tests__/memory.test.ts |  7 +++++++
 packages/datastore/src/filter.ts                | 10 +++++-----
 2 files changed, 12 insertions(+), 5 deletions(-)

diff --git a/packages/datastore/src/__tests__/memory.test.ts b/packages/datastore/src/__tests__/memory.test.ts
index 3fe979e2..9652d2fc 100644
--- a/packages/datastore/src/__tests__/memory.test.ts
+++ b/packages/datastore/src/__tests__/memory.test.ts
@@ -266,6 +266,13 @@ describe('filterToCosmosSQL', () => {
     expect(result.parameters).toHaveLength(2);
   });
 
+  it('$contains emits ARRAY_CONTAINS OR CONTAINS', () => {
+    const result = filterToCosmosSQL({ tags: { $contains: 'urgent' } });
+    expect(result.query).toContain('ARRAY_CONTAINS(c.tags, @p0)');
+    expect(result.query).toContain('CONTAINS(c.tags, @p0)');
+    expect(result.parameters).toEqual([{ name: '@p0', value: 'urgent' }]);
+  });
+
   it('$or', () => {
     const result = filterToCosmosSQL({ $or: [{ a: 1 }, { b: 2 }] });
     expect(result.query).toContain('OR');
diff --git a/packages/datastore/src/filter.ts b/packages/datastore/src/filter.ts
index 7f37282c..6ac78ae2 100644
--- a/packages/datastore/src/filter.ts
+++ b/packages/datastore/src/filter.ts
@@ -139,11 +139,11 @@ export function filterToCosmosSQL(filter: FilterMap): SqlQuery {
     }
 
     if (op.$contains !== undefined) {
-      // Could be array or string — use CONTAINS for string, ARRAY_CONTAINS for array
-      // In Cosmos SQL, we use ARRAY_CONTAINS for arrays and CONTAINS for strings
-      // Since we can't know the type at SQL-gen time, use CONTAINS (works for strings)
-      // Callers dealing with arrays should use ARRAY_CONTAINS via rawQuery
-      parts.push(`CONTAINS(c.${key}, ${nextParam(op.$contains)})`);
+      // Could be array or string — emit both ARRAY_CONTAINS and CONTAINS.
+      // Cosmos returns false (not error) when the function doesn't match the field type,
+      // so OR-ing them handles both array membership and string substring correctly.
+      const param = nextParam(op.$contains);
+      parts.push(`(ARRAY_CONTAINS(c.${key}, ${param}) OR CONTAINS(c.${key}, ${param}))`);
     }
 
     if (op.$in !== undefined) {