diff --git a/packages/core/src/__tests__/memdb.test.ts b/packages/core/src/__tests__/memdb.test.ts
index ccdab87043..f518944c6e 100644
--- a/packages/core/src/__tests__/memdb.test.ts
+++ b/packages/core/src/__tests__/memdb.test.ts
@@ -430,5 +430,18 @@ describe('memdb', () => {
 
     expect(mergeQueries({ age: { $lt: 20 } } as any, { age: { $gt: 25 } } as any)).toEqual({ age: { $gt: 25 } })
     expect(mergeQueries({ age: { $gt: 25 } } as any, { age: { $lt: 20 } } as any)).toEqual({ age: { $lt: 20 } })
+
+    const query4 = {
+      space: { $in: [id1] }
+    } as any
+    const query5 = {
+      space: { $in: [id2, id1] }
+    } as any
+    const resQuery45 = {
+      space: id1
+    } as any
+
+    expect(mergeQueries(query4, query5)).toEqual(resQuery45)
+    expect(mergeQueries(query5, query4)).toEqual(resQuery45)
   })
 })
diff --git a/packages/core/src/utils.ts b/packages/core/src/utils.ts
index c419a48972..56fe59acc4 100644
--- a/packages/core/src/utils.ts
+++ b/packages/core/src/utils.ts
@@ -378,7 +378,7 @@ function getInNiN (query1: any, query2: any): Object {
     aIn.length - bIn.length < 0 ? bIn.filter((c: any) => aIn.includes(c)) : aIn.filter((c: any) => bIn.includes(c))
   const finalNin = Array.from(new Set([...aNIn, ...bNIn]))
   if (finalIn.length === 1 && finalNin.length === 0) {
-    return aIn[0]
+    return finalIn[0]
   }
   if (finalIn.length === 0 && finalNin.length === 1) {
     return { $ne: finalNin[0] }