Mysql：从另一个表更新表的所有列

Question

I have two tables a_table and b_table and are initialised as:

create table a_table(
id int not null auto_increment primary key,
reference varchar(255),
colour varchar(255),
size varchar(255),
unique (reference)
);

insert into a_table (reference, colour, size) values
('ref1', 'red', 'big'),
('ref2', 'blue', 'small'),
('ref3', 'green', 'mini');

create table b_table(
id int not null auto_increment primary key,
reference varchar(255),
colour varchar(255),
size varchar(255),
unique (reference)
);

insert into b_table (reference, colour, size) values
('ref1', 'orange', 'tiny'),
('ref2', 'orange', 'tiny'),
('ref3', 'orange', 'tiny'),
('ref4', 'pink', 'large'),
('ref5', 'yellow', 'huge'),
('ref6', 'purple', 'small');

I want to update a_table with the information from b_table, and can do so with the command

update a_table a, b_table b
set a.colour = b.colour,
a.size = b.size
where
a.reference = b.reference

What I would like to know is if there is a simpler way to list all the columns to update? so doing away with

a.colour = b.colour,
a.size = b.size

Seems ok here as there are just two columns, but if there were 100s of columns this could get tedious. I want to avoid using

replace into a_table select * from b_table

https://dbfiddle.uk/?rdbms=mysql_8.0&fiddle=bf179cbbfb090e78acf542c6ddeec0f5 to follow along the example above

One solution could be to create an array containing the column names, and then looping through the array to create

a.colour = b.colour,
a.size = b.size

Would anyone be able to show how this could be done in Mysql?

Answer 1

Dear if there is only option of updating table rows from other table , you must mention all the columns if they are hundreds or thousands in count. If you want to insert rows from other table, then there is a simple way. The best and optimized way will be that: Write a script or code whatever you are best at. Put the columns in an array and make a query builder for this purpose. Then run / execute the query. looking forward for further assistance