mysqld 升級到8以上遇到的問題

coav4u

(1)
0 J6 b' m& }* Y3 I2 J/ w. |php連到mysql出現2行errors : (discuz網頁出現的是連接到mysql錯誤表格,需自行寫一隻連接mysql的php程式來測試)

0 q  G5 n, n6 C* i' r1 ^: S& x( G8 qmysqli_real_connect(): Server sent charset (255) unknown to the client. Please, report to the developers
) f4 s% g+ B% ]5 {mysqli_real_connect(): (HY000/2054): Server sent charset unknown to the client. Please, report to the developers
% S, m# ?$ W0 \2 O& V* t2 I; V原因:
在MySQL 8.0.21中，caching_sha2_password是默認的身份驗證插件，而不是以往的mysql_native_password。所以和php不相容。可以降級php，也可以修改MySQL的配置。 吾人決定修改MySQL的配置:
* q, x" j* |0 ~$ p2 h$ ~6 Pvi /etc/my.cnf  加入下列:
& y2 o; S* s5 k! v9 l0 Y[mysqld]
* |1 {# L. H2 S# V+ B7 c
4 q- n$ l% o* |5 j$ {character-set-server=utf8
( U7 b0 b+ L, `) E+ c* O$ U6 `default_authentication_plugin=mysql_native_password
0 `8 V7 U; b$ Pvalidate_password.policy=LOW
[mysql]
" K3 m0 I  z2 Y. n) x+ r- E: v3 ]default-character-set=utf8
4 e7 X9 @3 P$ r
& x3 e  `( Z/ K- \[client]
0 T2 ^; n5 c( {default-character-set=utf8
; q! Z) i+ h& U: y: n; L
% q8 Y! R/ P3 G/ \. @- V然後重啟mysqld
service mysqld restart

重啟後可能須做下列動作:
3 G, h  y6 |7 a0 Z% ~* H" Pmysql -u roor -p  
SHOW VARIABLES LIKE 'validate_password%';
SET GLOBAL validate_password_policy=LOW;ALTER USER 'root'@'localhost' IDENTIFIED WITH mysql_native_password BY '你的密碼';搞定!!
1 s/ [2 [- W, b1 S& U
註: mysqld啟動時,在/var/log/mysql/mysqld.log紀錄著:註: 可以先寫支php程式以測試 ~~~
; @+ E7 `* B  Q4 v$ h8 J

1. <?
   
2. $hostname = "x.x.x.x";
   7 V8 t5 u% c' P3 ^
3. $database = "db_name";
   & k1 L  U2 B2 A$ w% H* v/ L
4. $username = "user_name";
   
5. $password = "pwd";
   5 j! L# A  p/ f6 H
6. 
   
7. $conn = mysqli_connect($hostname, $username, $password,$database) or trigger_error(mysql_error(),E_USER_ERROR);
   ( u. J9 O( X; B3 M# m
8. mysqli_query($conn ,"SET NAMES utf8");
   
9. 
   
10. $sql = "select count(*) as total from " .  "table_name";
    8 S$ V  {; p7 C! F6 Q
11. $rec = mysqli_fetch_assoc(mysqli_query( $conn,$sql));
    
12. echo $rec['total'];
    
13. mysqli_close($conn);
    
14. ?>

複製代碼

遊客，本帖隱藏的內容需要積分高於 999999999999 才可瀏覽，您當前積分為 0

% e2 g* m0 E& L- @& ^當php 7.2.24  connect to mysql server,出現 :

1. PHP Fatal error:  Uncaught Error: Call to undefined function mysqli_connect() in /test/connectmysql8.php:9
   
2. Stack trace:
   
3. #0 {main}
   
4.   thrown in /test/connectmysql8.php on line 9
     M$ l& h5 b# Z8 Z
5. 
   & d% ]5 G2 _; ?6 K$ Z
6. Fatal error: Uncaught Error: Call to undefined function mysqli_connect() in /test/connectmysql8.php:9
   
7. Stack trace:
   5 E: M8 R8 d9 U
8. #0 {main}
   
9.   thrown in /test/connectmysql8.php on line 9

複製代碼

這是版本相依的問題,只要 yum install php-mysqlnd  或 yum install php-mysqli 即可

+ X0 c9 p+ Q0 j# S! u
[Warning] [MY-013242] [Server] --character-set-server: 'utf8' is currently an alias for the character set UTF8MB3, but will be an alias for UTF8MB4 in a future release. Please consider using UTF8MB4 in order to be unambiguous.
$ \# M+ [3 c# U; |8 [* g說明: 千萬不能照它建議用"UTF8MB4",否則無法成功啟動

0 C# E5 O3 z1 U(2)
. X0 u9 P, B0 k7 I! _2 P(1064) You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'system>0' at line 1
; b" h# ?5 {, p6 K  u2 ?) I/ RSELECT COUNT(*) FROM common_usergroup WHERE type='special' and system>0
: P. s( j4 z/ [' `
/ B- n- C; `& X(1064) You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'groups = '' AND starttime<=1532077291 AND (endtime>=1532077291 OR endtime=0) ORD' at line 1
SELECT * FROM forum_announcement WHERE type!=2 AND groups = '' AND starttime<=1532077291 AND (endtime>=1532077291 OR endtime=0) ORDER BY displayorder, starttime DESC, id DESC LIMIT 1

+ M) r0 q, `" g因為MySQL 8.0+將system和groups作為了關鍵字，所以不能直接在SQL中將system和groups這兩個詞作為數據庫、數據表、數據表字段中的任意一種使用，如果數據庫名或數據表名或數據表字段名使用了system或groups作為名字，必須使用一對反引號引用起來。寫作`system`或`groups`。

第一個錯誤需要找到Discuz!目錄中的source\class\table\table_common_usergroup.php，
將文件中所有的system全部改成`system`，保存後重新上傳到服務器的相同目錄即可。
1 l' S! _: T2 ]/ {, h
7 n  ~% x3 D" A1 ]7 R! B9 t第二個錯誤需要找到Discuz!目錄下中的source\class\table\table_forum_announcement.php，
將文件中所有的groups全部改為`groups`，保存後重新上傳到服務器的相同目錄即可。
1 k, A: c) ?7 ?0 C
如果在MySQL 8+環境下安裝Discuz!，在安裝前需要給install\data\install.sql文件中沒有加引號的所有system逐一添加一對反引號保存重新上傳到服務器的相同目錄，否則也會出現SQL語法錯誤。
. S4 T/ \# F" r
9 q$ n. Q  s5 C# i5 ^為了避免語法錯誤，在寫SQL語句時，一定要為所有的數據庫名、數據表名、數據表字段名全部添加一對反引號，像Discuz!這樣的寫法是很不妥的。
& E! A2 H) r% y" h$ b以上參考:   升級到 MySQL 8.0+ 後Discuz! 更新緩存時出現SQL語法錯誤

" V  {) Z8 e$ T- Z. ~  l: E3 V0 P! U