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Why is this SQL code not working?

I created 3 different tables, and for him it is

CREATE TABLE `shirt` ( `id` int(11) not null, `name` varchar(32), PRIMARY KEY (`id`) ) ENGINE=MyISAM DEFAULT CHARSET=latin1; INSERT INTO `shirt` (`id`, `name`) VALUES ('1', 'vneck'), ('2', 'scoop neck'); CREATE TABLE `shirt_size` ( `shirtId` int(11) not null, `sizeId` int(11) not null, PRIMARY KEY (`shirtId`,`sizeId`), KEY `sizeId` (`sizeId`) ) ENGINE=MyISAM DEFAULT CHARSET=latin1; INSERT INTO `shirt_size` (`shirtId`, `sizeId`) VALUES ('1', '2'), ('1', '3'), ('1', '4'), ('1', '5'), ('2', '1'), ('2', '2'), ('2', '3'), ('2', '4'), ('2', '5'), ('2', '6'), ('2', '7'); CREATE TABLE `size` ( `id` int(11) not null, `name` varchar(4), PRIMARY KEY (`id`) ) ENGINE=MyISAM DEFAULT CHARSET=latin1; INSERT INTO `size` (`id`, `name`) VALUES ('1', 'xs'), ('2', 's'), ('3', 'm'), ('4', 'l'), ('5', '1x'), ('6', '2x'), ('7', '3x');

and I request it with

 SELECT shirt.name, size.name FROM shirt INNER JOIN shirt_size ON shirt_size.shirtId = shirt.id INNER JOIN size ON size.id = shirt_size.sizeId

but in a table that only shows the name of the shirt, I need a size column to display on the screen too. In the FROM part, I put shirt, size , but I got an error. Looking further, I saw that many people only put the first name of the table in the FROM part. I do not see how it should represent the column size.name . What am I doing wrong?

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1 answer

They have the same column name (albeit from different tables). You need to specify ALIAS in one of the columns (or both), for example

 SELECT shirt.name as ShirtName, size.name as SizeName FROM shirt INNER JOIN shirt_size ON shirt_size.shirtId = shirt.id INNER JOIN size ON size.id = shirt_size.sizeId
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