Bug #90236 mysql client use --default-character-set=binary may cause synax error
Submitted: 28 Mar 2018 2:22 Modified: 2 Apr 2018 7:07
Reporter: Xiao Jian XIA Email Updates:
Status: Verified Impact on me:
None 
Category:MySQL Server: Command-line Clients Severity:S3 (Non-critical)
Version:5.6, 5.7 OS:Any
Assigned to: CPU Architecture:Any

[28 Mar 2018 2:22] Xiao Jian XIA
Description:
use mysqlbinlog to process binlog file and load to mysql server by mysql client.
But when we use mysql client assigned --default-character-set=binary, we got an error: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 ';\x0A\x0A\x0ASET TIMESTAMP=1521886260' at line 1

mysql> DELIMITER aa;
mysql> select 1 aa
+---+
| 1 |
+---+
| 1 |
+---+
1 row in set (0.00 sec)

mysql> delimiter ab;
mysql> select 1 ab;
+---+
| 1 |
+---+
| 1 |
+---+
1 row in set (0.00 sec)

How to repeat:
1. use 5.6/5.7 mysql client connect mysql server,assign --default-character-set=binary
2. execute sql:
   DELIMITER /*!*/;
3. execute sql:
   SET TIMESTAMP=1521894432/*!*/;

error happend:
 ERROR 1064 (42000) at line 7: 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 ';\x0A\x0A\x0ASET TIMESTAMP=1521886260' at line 1

Suggested fix:
This error was caused by incorrect execute:DELIMITER /*!*/;
In correct situation, after execute this command,the DELIMITER should be set to:/*!*/;(with semicolon)
Actually, the DELIMITER had been set to /*!*/ (without semicolon)

The reason for this is caused by character_set, any case sensitive character_set had the same problem
mysql client function use is_delimiter_command to judge whether is a delimiter command ,this function use the client character(--default-chacter-set) to compare string.
But in another code logic(find_command),use fixed my_charset_latin1 to judge

To fix this bug,we only need to assgined a fixed charset my_charset_latin1,this modify only affect mysql client command DELIMITER.

--- a/client/mysql.cc
+++ b/client/mysql.cc
@@ -1181,7 +1181,7 @@ inline bool is_delimiter_command(char *name, ulong len)
     only name(first DELIMITER_NAME_LEN bytes) is checked.
   */
   return (len >= DELIMITER_NAME_LEN &&
-          !my_strnncoll(charset_info, (uchar*) name, DELIMITER_NAME_LEN,
+          !my_strnncoll(&my_charset_latin1, (uchar*) name, DELIMITER_NAME_LEN,
                         (uchar *) DELIMITER_NAME, DELIMITER_NAME_LEN));
 }
[2 Apr 2018 4:11] Vin Chen
It's really a bug
[2 Apr 2018 7:07] MySQL Verification Team
Hello Xiao Jian XIA,

Thank you for the report.

Thanks,
Umesh