INSERT ON DUPLICATE KEY with INNER JOIN - mysql

Question

Given t.id, a.id, t1.name and t2.name, how do I add or update t1_has_t2.data?
I can update it if there is currently a record.
UPDATE t1_has_t2
INNER JOIN t1 ON t1.id=t1_has_t2.t1_id
INNER JOIN t2 ON t2.id=t1_has_t2.t2_id
SET t1_has_t2.data=123
WHERE t1.name="foo" AND t1.t_id=333 AND t2.name="bar" AND t2.t_id=333;
How can I insert it if a record currently doesn't exist?
EDIT. Would it be something like the following? Seems a waste to include t in the JOIN.
INSERT INTO t1_has_t2(t1_id,t2_id,data)
SELECT t1.id, t2.id, 123
FROM t
INNER JOIN t1 ON t1.t_id=t.id
INNER JOIN t2 ON t2.t_id=t.id
WHERE t1.name="foo" AND t1.t_id=333 AND t2.name="bar" AND t2.t_id=333
ON DUPLICATE KEY SET t1_has_t2.data=123;
EDIT2. Ah, maybe I get it now. I just JOIN t1 and t2 to each other through their shared t.id?
INSERT INTO t1_has_t2(t1_id,t2_id,data)
SELECT t1.id, t2.id, 123
FROM t1
INNER JOIN t2 ON t2.t_id=t1.t_id
WHERE t1.name="foo" AND t1.t_id=333 AND t2.name="bar" AND t2.t_id=333
ON DUPLICATE KEY UPDATE t1_has_t2.data=123;
-- MySQL Script generated by MySQL Workbench
-- 08/08/16 07:40:04
-- Model: New Model Version: 1.0
SET #OLD_UNIQUE_CHECKS=##UNIQUE_CHECKS, UNIQUE_CHECKS=0;
SET #OLD_FOREIGN_KEY_CHECKS=##FOREIGN_KEY_CHECKS, FOREIGN_KEY_CHECKS=0;
SET #OLD_SQL_MODE=##SQL_MODE, SQL_MODE='TRADITIONAL,ALLOW_INVALID_DATES';
-- -----------------------------------------------------
-- Schema mydb
-- -----------------------------------------------------
CREATE SCHEMA IF NOT EXISTS `mydb` DEFAULT CHARACTER SET utf8 COLLATE utf8_general_ci ;
USE `mydb` ;
-- -----------------------------------------------------
-- Table `mydb`.`accounts`
-- -----------------------------------------------------
CREATE TABLE IF NOT EXISTS `mydb`.`accounts` (
`id` INT NOT NULL AUTO_INCREMENT,
PRIMARY KEY (`id`))
ENGINE = InnoDB;
-- -----------------------------------------------------
-- Table `mydb`.`t`
-- -----------------------------------------------------
CREATE TABLE IF NOT EXISTS `mydb`.`t` (
`id` INT NOT NULL AUTO_INCREMENT,
`accounts_id` INT NOT NULL,
PRIMARY KEY (`id`, `accounts_id`),
INDEX `fk_t_accounts_idx` (`accounts_id` ASC),
CONSTRAINT `fk_t_accounts`
FOREIGN KEY (`accounts_id`)
REFERENCES `mydb`.`accounts` (`id`)
ON DELETE NO ACTION
ON UPDATE NO ACTION)
ENGINE = InnoDB;
-- -----------------------------------------------------
-- Table `mydb`.`t1`
-- -----------------------------------------------------
CREATE TABLE IF NOT EXISTS `mydb`.`t1` (
`id` INT NOT NULL AUTO_INCREMENT,
`t_id` INT NOT NULL,
`t_accounts_id` INT NOT NULL,
`name` VARCHAR(45) NULL,
PRIMARY KEY (`id`),
INDEX `fk_t1_t1_idx` (`t_id` ASC, `t_accounts_id` ASC),
UNIQUE INDEX `un1` (`t_id` ASC, `name` ASC),
CONSTRAINT `fk_t1_t1`
FOREIGN KEY (`t_id` , `t_accounts_id`)
REFERENCES `mydb`.`t` (`id` , `accounts_id`)
ON DELETE NO ACTION
ON UPDATE NO ACTION)
ENGINE = InnoDB;
-- -----------------------------------------------------
-- Table `mydb`.`t2`
-- -----------------------------------------------------
CREATE TABLE IF NOT EXISTS `mydb`.`t2` (
`id` INT NOT NULL AUTO_INCREMENT,
`t_id` INT NOT NULL,
`t_accounts_id` INT NOT NULL,
`name` VARCHAR(45) NULL,
PRIMARY KEY (`id`),
INDEX `fk_t2_t1_idx` (`t_id` ASC, `t_accounts_id` ASC),
UNIQUE INDEX `un2` (`t_id` ASC, `name` ASC),
CONSTRAINT `fk_t2_t1`
FOREIGN KEY (`t_id` , `t_accounts_id`)
REFERENCES `mydb`.`t` (`id` , `accounts_id`)
ON DELETE NO ACTION
ON UPDATE NO ACTION)
ENGINE = InnoDB;
-- -----------------------------------------------------
-- Table `mydb`.`t1_has_t2`
-- -----------------------------------------------------
CREATE TABLE IF NOT EXISTS `mydb`.`t1_has_t2` (
`t1_id` INT NOT NULL,
`t2_id` INT NOT NULL,
`data` VARCHAR(45) NULL,
PRIMARY KEY (`t1_id`, `t2_id`),
INDEX `fk_t1_has_t2_t21_idx` (`t2_id` ASC),
INDEX `fk_t1_has_t2_t11_idx` (`t1_id` ASC),
CONSTRAINT `fk_t1_has_t2_t11`
FOREIGN KEY (`t1_id`)
REFERENCES `mydb`.`t1` (`id`)
ON DELETE NO ACTION
ON UPDATE NO ACTION,
CONSTRAINT `fk_t1_has_t2_t21`
FOREIGN KEY (`t2_id`)
REFERENCES `mydb`.`t2` (`id`)
ON DELETE NO ACTION
ON UPDATE NO ACTION)
ENGINE = InnoDB;
SET SQL_MODE=#OLD_SQL_MODE;
SET FOREIGN_KEY_CHECKS=#OLD_FOREIGN_KEY_CHECKS;
SET UNIQUE_CHECKS=#OLD_UNIQUE_CHECKS;

Answer 1

Works fine if I understand what you want with Insert on Duplicate Key Update (IODKU).
Data Load:
insert accounts(id) values (NULL); -- id = 1
insert t(accounts_id) values (1); -- id = 1
insert t1(t_id,t_accounts_id,name) values (1,1,'n1'); -- id=1
insert t1(t_id,t_accounts_id,name) values (1,1,'n2'); -- id=2
insert t2(t_id,t_accounts_id,name) values (1,1,'n1'); -- id=1
insert t2(t_id,t_accounts_id,name) values (1,1,'n2'); -- id=2
insert t1_has_t2(t1_id,t2_id,data) values(1,1,'one_one'); -- success
insert t1_has_t2(t1_id,t2_id,data) values(1,77,'x'); -- Error 1452 as expected
insert t1_has_t2(t1_id,t2_id,data) values(77,1,'x'); -- Error 1452 as expected
insert t1_has_t2(t1_id,t2_id,data) values(1,2,'one_two'); -- success
insert t1_has_t2(t1_id,t2_id,data) values(2,1,'two_one'); -- success
insert t1_has_t2(t1_id,t2_id,data) values(2,2,'two_two'); -- success
Your Query:
UPDATE t1_has_t2
INNER JOIN t1 ON t1.id=t1_has_t2.t1_id
INNER JOIN t2 ON t2.id=t1_has_t2.t2_id
SET t1_has_t2.data='I am a string'
WHERE t1.name="n1" AND t1.t_id=1 AND t2.name="n1" AND t2.t_id=1;
IODKU:
insert t1_has_t2(t1_id,t2_id,data) values(2,2,'two_two_version002')
on duplicate key update data='anchovies';
See results:
select * from t1_has_t2;
+-------+-------+---------------+
| t1_id | t2_id | data |
+-------+-------+---------------+
| 1 | 1 | I am a string |
| 1 | 2 | one_two |
| 2 | 1 | two_one |
| 2 | 2 | anchovies |
+-------+-------+---------------+
You can also look into
insert ignore t1_has_t2(t1_id,t2_id,data) [something];
Which succeeds or fails silently by design.