feat: health check db

docs/2022-07-31-sql.html

@@ -240,6 +240,16 @@
         >
       </li>
     </ul>
+    <h2>
+      <a
+        id="user-content-heathcheck"
+        class="anchor"
+        aria-hidden="true"
+        href="#heathcheck"
+        ><span aria-hidden="true" class="octicon octicon-link"></span></a
+      >Heathcheck
+    </h2>
+    <p>Use <code>SELECT 1</code> to check if database failed yet.</p>
     <h2>
       <a id="user-content-tools" class="anchor" aria-hidden="true" href="#tools"
         ><span aria-hidden="true" class="octicon octicon-link"></span></a
@@ -306,6 +316,13 @@
           >How to read MySQL EXPLAINs</a
         >
       </li>
+      <li>
+        <a
+          href="https://brandur.org/fragments/database-health-check"
+          rel="nofollow"
+          >Honest health checks that hit the database</a
+        >
+      </li>
     </ul>
 
     <div>

posts/2022-07-31-sql.md

@@ -110,6 +110,10 @@ database running the same time update it, for example create index, ...)
 - [For MySQL 8.0](https://dev.mysql.com/doc/refman/8.0/en/innodb-online-ddl-operations.html),
   [Limitations](https://dev.mysql.com/doc/refman/8.0/en/innodb-online-ddl-limitations.html)
 
+## Heathcheck
+
+Use `SELECT 1` to check if database failed yet.
+
 ## Tools
 
 - Use [sqlfluff/sqlfluff](https://github.com/sqlfluff/sqlfluff) to check your
@@ -125,3 +129,4 @@ database running the same time update it, for example create index, ...)
 - [When to use JSON data type in database schema design?](https://shekhargulati.com/2022/01/08/when-to-use-json-data-type-in-database-schema-design/)
 - [My Notes on GitLab Postgres Schema Design](https://shekhargulati.com/2022/07/08/my-notes-on-gitlabs-postgres-schema-design/)
 - [How to read MySQL EXPLAINs](https://planetscale.com/blog/how-read-mysql-explains)
+- [Honest health checks that hit the database](https://brandur.org/fragments/database-health-check)