MariaDB 10.3

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CREATE TABLE `clas` (
    `id` INT(10) UNSIGNED NOT NULL AUTO_INCREMENT,
    `term` SMALLINT(4) UNSIGNED NOT NULL,
    `subject` VARCHAR(10) NOT NULL DEFAULT '0' COLLATE 'utf8mb4_unicode_520_ci',
    `catalog` SMALLINT(5) UNSIGNED NOT NULL DEFAULT 0,
    `component` VARCHAR(10) NOT NULL DEFAULT '0' COLLATE 'utf8mb4_unicode_520_ci',
    `section` VARCHAR(5) NOT NULL DEFAULT '0' COLLATE 'utf8mb4_unicode_520_ci',
    PRIMARY KEY (`id`)
)
COLLATE='utf8mb4_unicode_520_ci'
ENGINE=InnoDB
;

CREATE TABLE `clas_import` (
    `id` INT(10) UNSIGNED NOT NULL AUTO_INCREMENT,
    `term` SMALLINT(4) UNSIGNED NOT NULL,
    `subject` VARCHAR(10) NOT NULL DEFAULT '0' COLLATE 'utf8mb4_unicode_520_ci',
    `catalog` SMALLINT(5) UNSIGNED NOT NULL DEFAULT 0,
    `component` VARCHAR(10) NOT NULL DEFAULT '0' COLLATE 'utf8mb4_unicode_520_ci',
    `section` VARCHAR(5) NOT NULL DEFAULT '0' COLLATE 'utf8mb4_unicode_520_ci',
    PRIMARY KEY (`id`)
)
COLLATE='utf8mb4_unicode_520_ci'
ENGINE=InnoDB
;
INSERT INTO `clas` VALUES
(182920,1730,'ENG',102,'LEC','1A04'),-- expecting match
(182921,1730,'ENG',102,'LEC','1A04');-- expecting match
    
    
INSERT INTO `clas_import` VALUES 
(1,1730,'ENG',102,'LEC','1A04'),-- both `clas` rows should match this row
(15,1730,'BLA',102,'LEC','1A04'),
(16,1730,'ENG',102,'LEC','1A04'),
(17,1730,'ENG',102,'LEC','1A04');
select clas.*
from clas
left join clas_import ci on
            clas.term      = ci.term AND
            clas.subject   = ci.subject AND
            clas.catalog   = ci.catalog AND
            clas.component = ci.component AND
            clas.section   = ci.section
where ci.id is null and
      clas.term in (1730)
DELETE
    FROM `clas`
WHERE
    `clas`.`term` IN (1730) AND
    NOT EXISTS(
        SELECT
            1
        FROM
            `clas_import` as `ci`
        WHERE
            `clas`.`term`      = `ci`.`term` AND
            `clas`.`subject`   = `ci`.`subject` AND
            `clas`.`catalog`   = `ci`.`catalog` AND
            `clas`.`component` = `ci`.`component` AND
            `clas`.`section`   = `ci`.`section`
        )
select * from clas;


id
term
subject
catalog
component
section


182920
1730
ENG
102
LEC
1A04

182921
1730
ENG
102
LEC
1A04