SQL JOIN

SELECT * FROM `a` INNER JOIN `b` USING(`id`); => tabulas savienojas pēc kopējas pazīmēs. id - vienādi nosaukumi;

SELECT * FROM `a` INNER JOIN `b` ON `a`.`id` = `b`.`mansid`;

 

SELECT `a`.`id` , `a`.`name`, `b`.`surname` FROM `a` INNER JOIN `b` ON `a`.`id` = `b`.`mansid`;

SELECT * FROM `a` LEFT JOIN `b` ON `a`.`id` = `b`.`mansid`; => galvenā tabula ir a, jā b tabula nebus, tad - null. INNER - paradīs tikai esošās;

SELECT * FROM `a` RIGHT JOIN `b` ON `a`.`id` = `b`.`mansid`;

SELECT * FROM `a` RIGHT JOIN `b` ON `a`.`id` = `b`.`mansid` LEFT JOIN `c` ON `b`.`surname` = `c`.`surname`;

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UPDATE `b` SET `kautkas` = 5 WHERE `name`='Mansvards'; ???

UPDATE `b` SET `kautkas` = 5 FROM `b` INNER JOIN `a` ON `b`.`id` = `a`.`id` WHERE `name`='Mansvards'; ???

UPDATE a,b SET b.kautkas=5

WHERE a.id=b.mansid AND a.name ='Mansvards';