Run exists() on the full element query if distinct, etc., are set

#15223 (comment)

CHANGELOG.md

@@ -6,6 +6,7 @@
 - Fixed a PHP error that could occur when running Codeception tests. ([#15445](https://github.com/craftcms/cms/issues/15445))
 - Fixed a bug where `deleteAsset`, `deleteCategory`, `deleteEntry`, and `deleteTag` GraphQL mutations were returning `null` rather than `true` or `false`. ([#15465](https://github.com/craftcms/cms/issues/15465))
 - Fixed a styling issue. ([#15473](https://github.com/craftcms/cms/issues/15473))
+- Fixed a bug where `exists()` element queries weren’t working if `distinct`, `groupBy`, `having,` or `union` params were set on them during query preparation. ([#15001](https://github.com/craftcms/cms/issues/15001), [#15223](https://github.com/craftcms/cms/pull/15223))
 
 ## 4.10.7 - 2024-07-29
 

src/elements/db/ElementQuery.php

@@ -1690,13 +1690,34 @@ public function exists($db = null): bool
         if ($cachedResult !== null) {
             return !empty($cachedResult);
         }
-        try {
-            return $this->prepareSubquery()
-                ->select('elements.id')
-                ->exists($db);
-        } catch (QueryAbortedException) {
-            return false;
+
+        if (
+            !$this->distinct
+            && empty($this->groupBy)
+            && empty($this->having)
+            && empty($this->union)
+        ) {
+            try {
+                $subquery = $this->prepareSubquery();
+
+                // If distinct, et al. were set by prepare(), don't mess with it
+                // see https://github.com/craftcms/cms/issues/15001#issuecomment-2174563927
+                if (
+                    !$subquery->distinct
+                    && empty($subquery->groupBy)
+                    && empty($subquery->having)
+                    && empty($subquery->union)
+                ) {
+                    return $subquery
+                        ->select('elements.id')
+                        ->exists($db);
+                }
+            } catch (QueryAbortedException) {
+                return false;
+            }
         }
+
+        return parent::exists($db);
     }
 
     /**