docs: add work log for 2026-06-15 and update DB deletion policy in README

scratch/find_public.cjs

@@ -0,0 +1,29 @@
+const mysql = require('mysql2/promise');
+require('dotenv').config();
+
+async function findPotentialPublic() {
+  const connection = await mysql.createConnection({
+    host: process.env.DB_HOST,
+    user: process.env.DB_USER,
+    password: process.env.DB_PASS,
+    database: process.env.DB_NAME,
+    port: parseInt(process.env.DB_PORT || '3306')
+  });
+
+  console.log('--- Searching for rows with no emp_no or "공용" in user_current ---');
+  
+  // 사번이 'undefined', 'null', 빈값, 또는 사용자명에 '공용'이 들어간 데이터
+  const [rows] = await connection.query(`
+    SELECT id, user_current, emp_no 
+    FROM asset_core 
+    WHERE id LIKE "PC_20260615_%" 
+      AND (emp_no IS NULL OR emp_no = '' OR emp_no = 'undefined' OR user_current LIKE '%공용%')
+  `);
+
+  console.log('Count:', rows.length);
+  if (rows.length > 0) console.table(rows);
+
+  await connection.end();
+}
+
+findPotentialPublic().catch(console.error);