diff --git a/web/app/models/UOJBlog.php b/web/app/models/UOJBlog.php
index caeb620..0f0a5c7 100644
--- a/web/app/models/UOJBlog.php
+++ b/web/app/models/UOJBlog.php
@@ -38,11 +38,10 @@ class UOJBlog {
 			return false;
 		}
 
-		if ($problem_id = $this->getSolutionProblemId()) {
-			$contests = UOJContest::queryContestsHasProblem(UOJProblem::query($problem_id));
-
-			foreach ($contests as $contest) {
-				if ($contest->userHasRegistered($user) && $contest->progress() == CONTEST_IN_PROGRESS) {
+		$problem = $this->getSolutionProblem();
+		if ($problem) {
+			foreach ($problem->findInContests() as $cp) {
+				if ($cp->contest->userHasRegistered($user) && $cp->contest->progress() == CONTEST_IN_PROGRESS) {
 					return false;
 				}
 			}
@@ -218,6 +217,15 @@ class UOJBlog {
 			],
 		]);
 	}
+
+	public function getSolutionProblem() {
+		return UOJProblem::query(DB::selectSingle([
+			DB::lc(), "select 1 from problems_solutions",
+			"where", [
+				"blog_id" => $this->info['id'],
+			],
+		]));
+	}
 }
 
 UOJBlog::$table_for_content = 'blogs';
diff --git a/web/app/models/UOJContest.php b/web/app/models/UOJContest.php
index ab3186e..2fd0ad7 100644
--- a/web/app/models/UOJContest.php
+++ b/web/app/models/UOJContest.php
@@ -28,16 +28,6 @@ class UOJContest {
 		]));
 	}
 
-	public static function queryContestsHasProblem(UOJProblem $problem) {
-		return array_map(fn ($x) => UOJContest::query($x['contest_id']), DB::selectAll([
-			"select contest_id from contests_problems",
-			"where", [
-				"problem_id" => $problem->info['id'],
-			],
-			"order by contest_id",
-		]));
-	}
-
 	public static function userCanManageSomeContest(array $user = null) {
 		if (!$user) {
 			return false;
diff --git a/web/app/models/UOJProblem.php b/web/app/models/UOJProblem.php
index 48fc537..106ada0 100644
--- a/web/app/models/UOJProblem.php
+++ b/web/app/models/UOJProblem.php
@@ -289,10 +289,8 @@ class UOJProblem {
 			return false;
 		}
 
-		$contests = UOJContest::queryContestsHasProblem($this);
-
-		foreach ($contests as $contest) {
-			if ($contest->userHasRegistered($user) && $contest->progress() <= CONTEST_IN_PROGRESS) {
+		foreach ($this->findInContests() as $cp) {
+			if ($cp->contest->userHasRegistered($user) && $cp->contest->progress() == CONTEST_IN_PROGRESS) {
 				return false;
 			}
 		}
@@ -326,12 +324,10 @@ class UOJProblem {
 	}
 
 	public function additionalSubmissionComponentsCannotBeSeenByUser(array $user = null, UOJSubmission $submission) {
-		$contests = UOJContest::queryContestsHasProblem($this);
-
-		foreach ($contests as $contest) {
-			if ($contest->userHasRegistered($user) && $contest->progress() == CONTEST_IN_PROGRESS) {
+		foreach ($this->findInContests() as $cp) {
+			if ($cp->contest->userHasRegistered($user) && $cp->contest->progress() == CONTEST_IN_PROGRESS) {
 				if ($submission->userIsSubmitter($user)) {
-					if ($contest->getJudgeTypeInContest() == 'no-details') {
+					if ($cp->contest->getJudgeTypeInContest() == 'no-details') {
 						return ['low_level_details'];
 					} else {
 						return [];