MySQL Bugs: #75700: Cannot create MySQL database with name '5e370227

Bug #75700	Cannot create MySQL database with name '5e370227_db'
Submitted:	30 Jan 2015 12:40	Modified:	30 Jan 2015 17:30
Reporter:	John Hardy	Email Updates:
Status:	Verified	Impact on me:	None
Category:	MySQL Server: Parser	Severity:	S3 (Non-critical)
Version:	mysql Ver 14.14 Distrib 5.1.73	OS:	Linux (Centos 2.6.32-358.el6.x86_64)
Assigned to:		CPU Architecture:	Any

Description:
I am getting error when I try to create database with name '5e370227_db'.

mysql> create database 5e370227_db;
ERROR 1064 (42000): 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 '5e370227_db' at line 1

When I try to create a database with name '5a370227_db' (e -> a) it is created successfully:

mysql> create database 5a370227_db;
Query OK, 1 row affected (0.00 sec)
Details:

MYSQL: mysql Ver 14.14 Distrib 5.1.73, for redhat-linux-gnu (x86_64) using readline 5.1
Linux Centos 2.6.32-358.el6.x86_64
logged as root
database admin

(http://dba.stackexchange.com/questions/90619/cannot-create-mysql-database-with-name-5e3702...)

How to repeat:
run a command in mysql: create database 5e370227_db;

Also reproducible on MySQL 5.6.22

-- Peter
-- not a MySQL/Oracle person

This works: CREATE DATABASE `5e370227_db`;

So "5e370227" seems to get parsed as a floating point number specifcation(!?). 
Should it in this context?

mysql> create database '5e370227_db';
ERROR 1064 (42000): 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 ''5e370227_db'' at line 1

mysql> create database "5e370227_db";
ERROR 1064 (42000): 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 '"5e370227_db"' at line 1

mysql> create database `5e370227_db`;
Query OK, 1 row affected (0.00 sec)

So only syntax with backticks works ...

Obviously.  You quote identifiers with backquotes.  Singlequotes and doublequotes are used quoting strings. (in non-ANSI sql_mode)

Undoubtedly MySQL thinks that "" is a number. http://dev.mysql.com/doc/refman/5.6/en/identifiers.html says "Identifiers may begin with a digit but unless quoted may not consist solely of digits.". But it does not list this case and the identifier here does no consist solely of numbers (but the server/parser evaluates it to such internally).  

I would call this a small bug or imperfection with the parser. I don't think the FLOAT evaluation code should trigger here at all.

I forgot to paste.  I meant: Undoubtedly MySQL thinks that "5e370227_db" is a number.

Please check with:

http://dev.mysql.com/doc/refman/5.1/en/identifiers.html

"It is recommended that you do not use names that begin with Me or MeN, where M and N are integers. For example, avoid using 1e as an identifier, because an expression such as 1e+3 is ambiguous. Depending on context, it might be interpreted as the expression 1e + 3 or as the number 1e+3. "

I will have to agree fully with Peter Laursen. It is a bug in the parser, but a bug that is with low priority.

Please, try to avoid identifier names that could be interpreted as IEEE floating point numbers.

Hence, it is fully verified.