MySQL Bugs: #6607: Create table... LIKE... with Windows Symlinks

Bug #6607	Create table... LIKE... with Windows Symlinks
Submitted:	13 Nov 2004 17:30	Modified:	8 Feb 2005 20:39
Reporter:	Fred Stiening
Status:	Closed
Category:	Server	Severity:	S2 (Serious)
Version:	4.1.7	OS:	Microsoft Windows (Windows XP Home)
Assigned to:	Reggie Burnett	Target Version:

Description:
If you attempt to create a table LIKE an existing table, and the source table is located
in a directory using the Windows .sym symlink feature to store the tables outside of the
normal data directory, the command returns "Unknown Table: source_table".

How to repeat:
example:

V:\code>mysql
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 5924 to server version: 4.1.7-nt

Type 'help;' or '\h' for help. Type '\c' to clear the buffer.

mysql> use thewww;
Database changed
mysql> show tables;
+---------------------+
| Tables_in_thewww    |
+---------------------+
| category            |
| classificationwords |
| httpservers         |
| ipaddress           |
| links               |
| querylog            |
| serverserverjoin    |
| topleveldomains     |
| urls                |
| urls_in             |
+---------------------+
10 rows in set (0.00 sec)

mysql> create table urls2 like urls;
ERROR 1051 (42S02): Unknown table 'urls'
mysql>

the table thewww is located on a different disk drive:

c:\mysql\data\thewww.sym contains:
z:\mysql\data\thewww\

In all other respects the symlink is working fine.

Suggested fix:
It would appear that the Create LIKE function is misssing the logic to follow Winodws
Symlinks - Create LIKE works correctly in the main data directory as well as on *nix.

got a patch

Note that a similar bug exists if the destination table is to be created in the .sym
database; one gets:
ERROR 1 (HY000): Can't create/write to file (Errcode: 2)

Apparently this patch works on Linux with -DUSE_SYMDIR but fails on Windows. So I am
donating it here to the Windows team for them to make something which works on Windows.
===== sql/sql_table.cc 1.261 vs edited =====
*** /home/guilhem/tmp/bk_sql_table.cc-1.261_zjO5Lc      2004-11-12 09:44:53 +01:00
--- edited/sql/sql_table.cc     2004-11-13 23:14:48 +01:00
***************
*** 2146,2153 ****
      strxmov(src_path, (*tmp_table)->path, reg_ext, NullS);
    else
    {
!     strxmov(src_path, mysql_data_home, "/", src_db, "/", src_table,
!           reg_ext, NullS);
      if (access(src_path, F_OK))
      {
        my_error(ER_BAD_TABLE_ERROR, MYF(0), src_table);
--- 2146,2152 ----
      strxmov(src_path, (*tmp_table)->path, reg_ext, NullS);
    else
    {
!     fn_format(src_path, src_table, src_db, reg_ext, MYF(MY_UNPACK_FILENAME));
      if (access(src_path, F_OK))
      {
        my_error(ER_BAD_TABLE_ERROR, MYF(0), src_table);
***************
*** 2174,2181 ****
    }
    else
    {
!     strxmov(dst_path, mysql_data_home, "/", db, "/", table_name,
!           reg_ext, NullS);
      if (!access(dst_path, F_OK))
        goto table_exists;
    }
--- 2173,2179 ----
    }
    else
    {
!     fn_format(dst_path, table_name, db, reg_ext, MYF(MY_UNPACK_FILENAME));
      if (!access(dst_path, F_OK))
        goto table_exists;
    }

Thank you for your bug report. This issue has been committed to our
source repository of that product and will be incorporated into the
next release.

If necessary, you can access the source repository and build the latest
available version, including the bugfix, yourself. More information 
about accessing the source trees is available at
    http://www.mysql.com/doc/en/Installing_source_tree.html

Fixed in 4.1, merged to 5.0

Mentioned in 4.1.10 and 5.0.3 change notes.