diff --git a/packages/backend/src/core/QueryService.ts b/packages/backend/src/core/QueryService.ts
index f85bed7295..3504573765 100644
--- a/packages/backend/src/core/QueryService.ts
+++ b/packages/backend/src/core/QueryService.ts
@@ -212,8 +212,8 @@ export class QueryService {
 				// または 自分自身
 					.orWhere('note.userId = :meId')
 				// または 自分宛て
-					.orWhere(':meId = ANY(note.visibleUserIds)')
-					.orWhere(':meId = ANY(note.mentions)')
+					.orWhere(':meIdAsList <@ note.visibleUserIds')
+					.orWhere(':meIdAsList <@ note.mentions')
 					.orWhere(new Brackets(qb => {
 						qb
 						// または フォロワー宛ての投稿であり、
@@ -228,7 +228,7 @@ export class QueryService {
 					}));
 			}));
 
-			q.setParameters({ meId: me.id });
+			q.setParameters({ meId: me.id, meIdAsList: [me.id] });
 		}
 	}
 
diff --git a/packages/backend/src/server/api/endpoints/drive/files/attached-notes.ts b/packages/backend/src/server/api/endpoints/drive/files/attached-notes.ts
index 14a13b09c9..7a0b8b4417 100644
--- a/packages/backend/src/server/api/endpoints/drive/files/attached-notes.ts
+++ b/packages/backend/src/server/api/endpoints/drive/files/attached-notes.ts
@@ -74,7 +74,7 @@ export default class extends Endpoint<typeof meta, typeof paramDef> { // eslint-
 			}
 
 			const query = this.queryService.makePaginationQuery(this.notesRepository.createQueryBuilder('note'), ps.sinceId, ps.untilId);
-			query.andWhere(':file = ANY(note.fileIds)', { file: file.id });
+			query.andWhere(':file <@ note.fileIds', { file: [file.id] });
 
 			const notes = await query.limit(ps.limit).getMany();
 
diff --git a/packages/backend/src/server/api/endpoints/hashtags/users.ts b/packages/backend/src/server/api/endpoints/hashtags/users.ts
index 50aea79943..8302d2380f 100644
--- a/packages/backend/src/server/api/endpoints/hashtags/users.ts
+++ b/packages/backend/src/server/api/endpoints/hashtags/users.ts
@@ -6,6 +6,7 @@
 import { Inject, Injectable } from '@nestjs/common';
 import { Endpoint } from '@/server/api/endpoint-base.js';
 import type { UsersRepository } from '@/models/_.js';
+import { safeForSql } from "@/misc/safe-for-sql.js";
 import { normalizeForSearch } from '@/misc/normalize-for-search.js';
 import { UserEntityService } from '@/core/entities/UserEntityService.js';
 import { DI } from '@/di-symbols.js';
@@ -47,8 +48,9 @@ export default class extends Endpoint<typeof meta, typeof paramDef> { // eslint-
 		private userEntityService: UserEntityService,
 	) {
 		super(meta, paramDef, async (ps, me) => {
+			if (!safeForSql(normalizeForSearch(ps.tag))) throw new Error('Injection');
 			const query = this.usersRepository.createQueryBuilder('user')
-				.where(':tag = ANY(user.tags)', { tag: normalizeForSearch(ps.tag) })
+				.where(':tag <@ user.tags', { tag: [normalizeForSearch(ps.tag)] })
 				.andWhere('user.isSuspended = FALSE');
 
 			const recent = new Date(Date.now() - (1000 * 60 * 60 * 24 * 5));
diff --git a/packages/backend/src/server/api/endpoints/notes/mentions.ts b/packages/backend/src/server/api/endpoints/notes/mentions.ts
index 6fab024d17..ef3819bafd 100644
--- a/packages/backend/src/server/api/endpoints/notes/mentions.ts
+++ b/packages/backend/src/server/api/endpoints/notes/mentions.ts
@@ -60,9 +60,9 @@ export default class extends Endpoint<typeof meta, typeof paramDef> { // eslint-
 
 			const query = this.queryService.makePaginationQuery(this.notesRepository.createQueryBuilder('note'), ps.sinceId, ps.untilId)
 				.andWhere(new Brackets(qb => {
-					qb
-						.where(`'{"${me.id}"}' <@ note.mentions`)
-						.orWhere(`'{"${me.id}"}' <@ note.visibleUserIds`);
+					qb // このmeIdAsListパラメータはqueryServiceのgenerateVisibilityQueryでセットされる
+						.where(':meIdAsList <@ note.mentions')
+						.orWhere(':meIdAsList <@ note.visibleUserIds');
 				}))
 				// Avoid scanning primary key index
 				.orderBy('CONCAT(note.id)', 'DESC')
diff --git a/packages/backend/src/server/api/endpoints/notes/search-by-tag.ts b/packages/backend/src/server/api/endpoints/notes/search-by-tag.ts
index b00f5207d8..0d7aca6621 100644
--- a/packages/backend/src/server/api/endpoints/notes/search-by-tag.ts
+++ b/packages/backend/src/server/api/endpoints/notes/search-by-tag.ts
@@ -87,14 +87,14 @@ export default class extends Endpoint<typeof meta, typeof paramDef> { // eslint-
 			try {
 				if (ps.tag) {
 					if (!safeForSql(normalizeForSearch(ps.tag))) throw new Error('Injection');
-					query.andWhere(`'{"${normalizeForSearch(ps.tag)}"}' <@ note.tags`);
+					query.andWhere(':tag <@ note.tags', { tag: [normalizeForSearch(ps.tag)] });
 				} else {
 					query.andWhere(new Brackets(qb => {
 						for (const tags of ps.query!) {
 							qb.orWhere(new Brackets(qb => {
 								for (const tag of tags) {
 									if (!safeForSql(normalizeForSearch(tag))) throw new Error('Injection');
-									qb.andWhere(`'{"${normalizeForSearch(tag)}"}' <@ note.tags`);
+									qb.andWhere(':tag <@ note.tags', { tag: [normalizeForSearch(tag)] });
 								}
 							}));
 						}