From 4bc8801e7f08a0d0f4f187951a830cd673c7f058 Mon Sep 17 00:00:00 2001
From: k4lizen <124312252+k4lizen@users.noreply.github.com>
Date: Fri, 10 Apr 2026 14:21:45 +0200
Subject: [PATCH] Add docs comment about deduplicating query rows

---
 docs/codeql/ql-language-reference/queries.rst | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/docs/codeql/ql-language-reference/queries.rst b/docs/codeql/ql-language-reference/queries.rst
index 8cba04942b62..76371728d66c 100644
--- a/docs/codeql/ql-language-reference/queries.rst
+++ b/docs/codeql/ql-language-reference/queries.rst
@@ -75,6 +75,10 @@ ordered according to the values in the ``y`` column, in descending order:
 | 3 | 0 | 0       | product: 0 |
 +---+---+---------+------------+
 
+A query may output identically duplicated rows because deduplication is done before ``.toString()``
+is called on the select expressions. If you wish to avoid this, explicitly call ``.toString()`` on the
+values in your select clause.
+
 .. _query-predicates:
 
 Query predicates