開發反饋執行sql時遇到報錯，sql語句非常簡單，語法是正確的，並且在該會話中執行什麼sql都會遇到以下報錯。
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2 Final//EN">
<title>500 Internal Server Error</title>
<h1>Internal Server Error</h1>
<p>The server encountered an internal error and was unable to complete your request. Either the server is overloaded or there is an error in the application.</p>
根據 Either the server is overloaded or there is an error in the application. 報錯信息，檢查DB負載情況，發現CPU不高，約爲30%，跟平時差不多。登錄DB中執行該sql發現執行正常，DB日誌也沒有相關報錯。
網上搜索該報錯發現好像跟應用關係比較大，開發反饋使用的是pgAdmin 4連接，嘗試關閉pgAdmin 4然後重新連接數據庫，發現前面sql均能正常執行，懷疑是pgAdmin 4的問題。
繼續搜索pgAdmin 4與該報錯，發現有人反饋過類似問題 https://www.postgresql.org/message-id/BN6PR1301MB2212264D059E8A1F5FD788DED4380@BN6PR1301MB2212.namprd13.prod.outlook.com
問題現象與pgAdmin版本都跟開發一致
Notes:
-The html is part of the message.
-It doesn’t seem to matter what query is sent.
-The actual query seems to stay active (as if it is still working), but eventually comes back with a wait event: ClientWrite.
-We can remedy the situation by closing the query tool window (hence closing the session) and opening a new query too window (whilst never closing pgAdmin 4 or the connection to the server) then sending the query again.
-We are connected to a Linux VM via my Windows 7 PC.
-This happens probably 10 times a day while queries are being developed and tested.I have:
Version
2.0
Copyright
Copyright 2013 - 2017, The pgAdmin Development Team
Python Version
2.7.13 (v2.7.13:a06454b1afa1, Dec 17 2016, 20:42:59) [MSC v.1500 32 bit (Intel)]
Flask Version
0.12.2
Application Mode
Desktop
Current User
pgadmin4(at)pgadmin(dot)org<mailto:pgadmin4(at)pgadmin(dot)org>
根據文檔中鏈接找到相關bug https://redmine.postgresql.org/issues/2806 （需要申請賬號才能打開）
不過這個文檔裏並沒有給修復方法，與開發同事溝通升級pgAdmin 4客戶端版本，使用最新版的前一版，繼續觀察
https://www.pgadmin.org/download/pgadmin-4-windows/
另外，pgAdmin4 V3.0版本開始不再以本地客戶端形式打開，而是以瀏覽器頁面方式展現。最後一個支持客戶端形式的版本是：V2.1。參考 https://www.zhangbj.com/p/333.html
