mysql導入MariaDB後用指令改URL報錯

mysql導入MariaDB後用指令改URL報錯
UPDATE wp_posts SET post_content = replace( post_content,’http://www.a.com’,’http://www.b.com’) ;

報錯
2 errors were found during analysis.

Unexpected character. (near ":" at position 53)
Unexpected character. (near ":" at position 83)
SQL query:

UPDATE wp_users SET user_url = replace(user_url,’http://www.a.com’, ‘http://www.b.com’)

MySQL said: Documentation

#1064 - You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near '://www.a.com’, ‘http://www.b.com’)' at line 1
懂的大大請指點如何改URL。 國外服務器的網站轉回NAS