Replace Into Query Syntax

Question

I want to be able to update a table of the same schema using a \"replace into\" statement. In the end, I need to be able to update a large table with values that may have c

Answer 1

or something like that:

insert ignore tbl1 (select * from tbl2);

UPDATE
        `tbl1` AS `dest`,
        (SELECT * FROM tbl2) AS `src`
    SET
       dest.field=src.field,
       dest.field=if (length(src.field)>0,src.field,dest.field) /* or anything like that*/
    WHERE
        `dest`.id = `src`.id;