MySQL - data exists update else insert

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INSERT INTO `table`(
	`pk`,
	`col_1`,
	`col_2`,
	`col_3`,
	`col_4`
)
VALUES
	(
		'1',
		'val_1',
		'val_2',
		'val_3',
		'val_4'
	)ON DUPLICATE KEY UPDATE `col_1` = 'val_1',
	`col_2` = 'val_2',
	`col_3` = 'val_3',
	`col_4` = 'val_4'INSERT INTO `table`(