maria-developers team mailing list archive

[Peter Laursen <peter_laursen@xxxxxxxxxx>]

Compare "generated columns" in MySQL 5.7.5 labs (refer
http://mysqlserverteam.com/generated-columns-in-mysql-5-7-5/).  It has
instrumentation in SHOW and I_S.  Please admit that this is a bug and an
oversight from MariaDB to forget about this!

Field    Type     Null    Key


select version(); -- 5.7.5-labs-preview

create table comments(
  userid int AS (ExtractValue(comment,'/comment/userid')) STORED,
  comment TEXT,
  KEY(userid));


show columns from comments;
/*Default  Extra
-------  -------  ------  ------  -------  ---------
userid   int(11)  YES     MUL     (NULL)   VIRTUAL
comment  text     YES             (NULL)
*/

describe comments;
/*
Field    Type     Null    Key     Default  Extra
-------  -------  ------  ------  -------  ---------
userid   int(11)  YES     MUL     (NULL)   VIRTUAL
comment  text     YES             (NULL)
*/

show full fields from comments;
/*
Field    Type     Collation          Null    Key     Default  Extra
 Privileges                       Comment
-------  -------  -----------------  ------  ------  -------  -------
 -------------------------------  ---------
userid   int(11)  (NULL)             YES     MUL     (NULL)   VIRTUAL
 select,insert,update,references
comment  text     latin1_swedish_ci  YES             (NULL)
 select,insert,update,references
*/

select * from information_schema.`COLUMNS` where TABLE_NAME = 'comments';

/*
TABLE_CATALOG  TABLE_SCHEMA  TABLE_NAME  COLUMN_NAME  ORDINAL_POSITION
 COLUMN_DEFAULT  IS_NULLABLE  DATA_TYPE  CHARACTER_MAXIMUM_LENGTH
 CHARACTER_OCTET_LENGTH  NUMERIC_PRECISION  NUMERIC_SCALE
 DATETIME_PRECISION  CHARACTER_SET_NAME  COLLATION_NAME     COLUMN_TYPE
 COLUMN_KEY  EXTRA    PRIVILEGES                       COLUMN_COMMENT
 GENERATION_EXPRESSION
-------------  ------------  ----------  -----------  ----------------
 --------------  -----------  ---------  ------------------------
 ----------------------  -----------------  -------------
 ------------------  ------------------  -----------------  -----------
 ----------  -------  -------------------------------  --------------
 -----------------------------------------
def            test          comments    userid                      1
 (NULL)          YES          int                          (NULL)
       (NULL)                 10              0              (NULL)  (NULL)
             (NULL)             int(11)      MUL         VIRTUAL
 select,insert,update,references
 ExtractValue(comment,'/comment/userid')
def            test          comments    comment                     2
 (NULL)          YES          text                          65535
        65535             (NULL)         (NULL)              (NULL)  latin1
             latin1_swedish_ci  text
 select,insert,update,references

*/

On Fri, Dec 26, 2014 at 1:28 PM, Peter Laursen <peter_laursen@xxxxxxxxxx>
wrote:

> This page
> https://mariadb.com/kb/en/mariadb/documentation/nosql/dynamic-columns-api/
> does not mention anything about it. it  just says
>
> *The API is a part of libmysql C client library. In order to use it, one
> needs to include this header file*
> *#include <mysql/ma_dyncol.h>*
> *and link against libmysql.*
>
> Now can ma_dyncol.h be linked against libmaria as well?
>
> There are 2 questions actually
> 1) technical: will it work with libmaria?
> 2) legal: can a client program using libmaria under LGPL license include
> ma_dyncol.h?
>
>
> -- Peter
> -- Webyog
>