Didn't CHECK CONSTRAINTS get introduced in MySQL 8? Then better port it from there into MariaDB I think.  -- Peter

 

On Sun, Oct 16, 2016 at 4:45 PM, Pantelis Theodosiou <ypercube@gmail.com> wrote:

Would this be good to be added in the documentation of VIRTUAL columns?

Or as a separate page, as a way to enforce/emulate arbitrary CHECK constraints?

It can be slightly simplified (IF is not needed) and the BOOLEAN could be BIT (not sure if that adds any complication):

CREATE TABLE truth (t BIT PRIMARY KEY) ;

INSERT INTO truth (t) VALUES (TRUE) ;   

-- and remove all write permissions to the table

CREATE TABLE checker ( 
    i float, 
    i_must_be_between_7_and_12 BIT
         AS (i BETWEEN 7 AND 12)                   -- whatever CHECK constraint we want here 
         PERSISTENT,

    CONSTRAINT check_i_must_be_between_7_and_12

    FOREIGN KEY (i_must_be_between_7_and_12)

      REFERENCES truth (t)

    );

On Wed, Apr 6, 2016 at 6:46 PM, Pantelis Theodosiou <ypercube@gmail.com> wrote: