diff --git a/docs/2022-07-31-sql.html b/docs/2022-07-31-sql.html
index 24a8e7b..3e4a5e0 100644
--- a/docs/2022-07-31-sql.html
+++ b/docs/2022-07-31-sql.html
@@ -105,7 +105,27 @@
       everything in there if you want.
     </p>
     <p>I always use MySQL json data type for extra field.</p>
-    <p>JSON data type also used for dumping request, response data.</p>
+    <p>JSON data type is also useful for dumping request, response data.</p>
+    <ul>
+      <li>
+        <a
+          href="https://dev.mysql.com/doc/refman/5.7/en/json.html"
+          rel="nofollow"
+          >For MySQL 5.7</a
+        >
+      </li>
+      <li>
+        <a
+          href="https://dev.mysql.com/doc/refman/8.0/en/json.html"
+          rel="nofollow"
+          >For MySQL 8.0</a
+        >
+      </li>
+    </ul>
+    <p>
+      Use <code>JSON_EXTRACT(col, '$.key') IS NULL</code> to check json field
+      exist or not.
+    </p>
     <h2>
       <a
         id="user-content-use-index"
diff --git a/docs/2023-06-06-terminal-workflow.html b/docs/2023-06-06-terminal-workflow.html
index 6c389c4..fdd7ed0 100644
--- a/docs/2023-06-06-terminal-workflow.html
+++ b/docs/2023-06-06-terminal-workflow.html
@@ -72,9 +72,9 @@
       <a
         target="_blank"
         rel="noopener noreferrer nofollow"
-        href="https://camo.githubusercontent.com/4567dca83cde7ee893659d05eff00ba7875b1afcbcccc74a6a2312311f076532/68747470733a2f2f7a656c6c696a2e6465762f646f63756d656e746174696f6e2f696d672f6f766572766965772d7374617475732d7461622d322e706e67"
+        href="https://camo.githubusercontent.com/111ef656bf49621be488e4ec5e1f440aafc1264f2ccfa5c051b7c1f3a26fa7ae/68747470733a2f2f7a656c6c696a2e6465762f646f63756d656e746174696f6e2f696d672f6f766572766965772d7374617475732d7461622d322e706e67"
         ><img
-          src="https://camo.githubusercontent.com/4567dca83cde7ee893659d05eff00ba7875b1afcbcccc74a6a2312311f076532/68747470733a2f2f7a656c6c696a2e6465762f646f63756d656e746174696f6e2f696d672f6f766572766965772d7374617475732d7461622d322e706e67"
+          src="https://camo.githubusercontent.com/111ef656bf49621be488e4ec5e1f440aafc1264f2ccfa5c051b7c1f3a26fa7ae/68747470733a2f2f7a656c6c696a2e6465762f646f63756d656e746174696f6e2f696d672f6f766572766965772d7374617475732d7461622d322e706e67"
           alt=""
           data-canonical-src="https://zellij.dev/documentation/img/overview-status-tab-2.png"
           style="max-width: 100%"
diff --git a/posts/2022-07-31-sql.md b/posts/2022-07-31-sql.md
index 1db7948..1ff0773 100644
--- a/posts/2022-07-31-sql.md
+++ b/posts/2022-07-31-sql.md
@@ -38,7 +38,12 @@ there if you want.
 
 I always use MySQL json data type for extra field.
 
-JSON data type also used for dumping request, response data.
+JSON data type is also useful for dumping request, response data.
+
+- [For MySQL 5.7](https://dev.mysql.com/doc/refman/5.7/en/json.html)
+- [For MySQL 8.0](https://dev.mysql.com/doc/refman/8.0/en/json.html)
+
+Use `JSON_EXTRACT(col, '$.key') IS NULL` to check json field exist or not.
 
 ## Use index!!!