From cd95d7d81c3dd16113b4b4839a0819f79906711c Mon Sep 17 00:00:00 2001
From: Yarchik <spoko.dev@gmail.com>
Date: Thu, 2 Jul 2026 12:34:00 +0100
Subject: [PATCH] fix(client): COPY with DB 0 must emit the DB argument

---
 packages/client/lib/commands/COPY.spec.ts | 9 +++++++++
 packages/client/lib/commands/COPY.ts      | 2 +-
 2 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/packages/client/lib/commands/COPY.spec.ts b/packages/client/lib/commands/COPY.spec.ts
index cd0c6ec9fb..5b58718b0d 100644
--- a/packages/client/lib/commands/COPY.spec.ts
+++ b/packages/client/lib/commands/COPY.spec.ts
@@ -23,6 +23,15 @@ describe('COPY', () => {
       );
     });
 
+    it('with destination DB flag set to 0', () => {
+      assert.deepEqual(
+        parseArgs(COPY, 'source', 'destination', {
+          DB: 0
+        }),
+        ['COPY', 'source', 'destination', 'DB', '0']
+      );
+    });
+
     it('with replace flag', () => {
       assert.deepEqual(
         parseArgs(COPY, 'source', 'destination', {
diff --git a/packages/client/lib/commands/COPY.ts b/packages/client/lib/commands/COPY.ts
index f26a930264..8caa66822e 100644
--- a/packages/client/lib/commands/COPY.ts
+++ b/packages/client/lib/commands/COPY.ts
@@ -12,7 +12,7 @@ export default {
     parser.push('COPY');
     parser.pushKeys([source, destination]);
 
-    if (options?.DB) {
+    if (options?.DB !== undefined) {
       parser.push('DB', options.DB.toString());
     }