mysqld 升級到8以上遇到的問題

coav4u

(1)
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)
9 \3 k/ c7 c  [8 [9 p/ W
6 O" ?* I. n5 P$ o- Imysqli_real_connect(): Server sent charset (255) unknown to the client. Please, report to the developers
mysqli_real_connect(): (HY000/2054): Server sent charset unknown to the client. Please, report to the developers
' q& E8 v4 F$ c' d4 n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:
vi /etc/my.cnf  加入下列:
$ k6 R  d0 ^. {# k  T9 r) [[mysqld]

character-set-server=utf8
$ ]. E9 ^; i5 X7 {9 D9 D( J2 Fdefault_authentication_plugin=mysql_native_password
" t9 g' u$ |8 v7 _' A4 Ivalidate_password.policy=LOW
' `. m0 ^' \6 W( l$ b- y1 c[mysql]
, I- V- z% N* y* H6 @default-character-set=utf8
* }* R) {; f0 c. I8 U0 C/ y
& Z* Y5 _2 A5 h4 a- n[client]
default-character-set=utf8

( {' h, r- W6 Q( C5 U: s6 Z! d  o然後重啟mysqld
service mysqld restart

重啟後可能須做下列動作:
' i% \/ R+ Z/ ]6 ]' s' nmysql -u roor -p  
$ r, T+ x: ?  l. g) C1 sSHOW 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!!
6 s" r& [  W$ S+ \% }+ Z4 I9 a
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 ~~~

1. <?
   - d4 i* S/ E9 Q- Z2 C3 V
2. $hostname = "x.x.x.x";
   ! x3 q3 t3 @; r) H8 k
3. $database = "db_name";
   ) b' e' {- I/ ~. I
4. $username = "user_name";
   1 q1 k5 _1 c+ U: q7 l
5. $password = "pwd";
   ) t! a( X; ]9 L0 {; I+ r( E- j  J
6. 
   
7. $conn = mysqli_connect($hostname, $username, $password,$database) or trigger_error(mysql_error(),E_USER_ERROR);
   7 t+ f! l1 J3 _
8. mysqli_query($conn ,"SET NAMES utf8");
   ' x( S2 b9 [9 e  u# |
9. 
   
10. $sql = "select count(*) as total from " .  "table_name";
    
11. $rec = mysqli_fetch_assoc(mysqli_query( $conn,$sql));
    
12. echo $rec['total'];
    
13. mysqli_close($conn);
    2 m( b9 r9 R4 w6 `
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

: l0 e* W: I3 J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
   % c" X# Y  K5 k1 d
2. Stack trace:
   : L7 B# a0 v1 s6 e
3. #0 {main}
   
4.   thrown in /test/connectmysql8.php on line 9
   , G% u$ b$ V6 h8 P
5. 
   , W% @+ z1 i! `( n
6. Fatal error: Uncaught Error: Call to undefined function mysqli_connect() in /test/connectmysql8.php:9
   $ |1 q8 l" T4 U/ _$ k8 [7 c
7. Stack trace:
   0 Q. O6 j, [) ?' T8 x* c% {. a
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
2 Q- a1 B" W8 c. h$ H; `4 f

[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.
說明: 千萬不能照它建議用"UTF8MB4",否則無法成功啟動

) z5 O; @7 Z% n% m" c2 F: p& H(2)
(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
SELECT COUNT(*) FROM common_usergroup WHERE type='special' and system>0

7 ]3 [  J% u8 ~& Z- A% U(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

) ~8 H/ s: U3 Q$ P1 Y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`。

% j  g5 `: I7 t1 G1 i3 D$ a+ i! x$ Y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。
5 P+ n' a. L, W1 J9 l7 P; o
) `4 G; Z3 A3 F第二個錯誤需要找到Discuz!目錄下中的source\class\table\table_forum_announcement.php，
% K" B* R: v4 k9 a+ e* p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。
7 X- X" t4 M$ q" i/ ?" K$ e
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。

: T' G  d* C$ `& ]9 r% a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。
以上參考:   升級到 MySQL 8.0+ 後Discuz! 更新緩存時出現SQL語法錯誤

/ i* @' O2 F6 `0 ?