MySQL 8.0

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select version();


version()


8.0.24


create table ta02 
(
  t_key      varchar(255) default null,
  ta_over_amount decimal(13,2) default null,
  name           varchar(255) default null
);
create table voucher 
(
  v_key       varchar(255) default null,
  over_amount decimal(13,2) default null,
  signature   varchar(255) default null
);
INSERT INTO ta02 (t_key, ta_over_amount, name) VALUES ('gogo', 100.00, 'anh');
INSERT INTO ta02 (t_key, ta_over_amount, name) VALUES ('gogo', 50.00, 'duc');
INSERT INTO ta02 (t_key, ta_over_amount, name) VALUES ('logbasex', 25.00, 'ho');
INSERT INTO ta02 (t_key, ta_over_amount, name) VALUES ('logbasex', 15.00, 'phi');
SELECT * FROM ta02;


t_key
ta_over_amount
name


gogo
100.00
anh

gogo
50.00
duc

logbasex
25.00
ho

logbasex
15.00
phi


INSERT INTO voucher (v_key, over_amount, signature) VALUES ('gogo', 100.00, 'blue');
INSERT INTO voucher (v_key, over_amount, signature) VALUES ('gogo', 50.00, 'white');
INSERT INTO voucher (v_key, over_amount, signature) VALUES ('logbasex', 14.00, 'itsme');
INSERT INTO voucher (v_key, over_amount, signature) VALUES ('logbasex', 25.00, 'green');
SELECT * FROM voucher;


v_key
over_amount
signature


gogo
100.00
blue

gogo
50.00
white

logbasex
14.00
itsme

logbasex
25.00
green


select t.name, t.ta_over_amount, v.over_amount, v.signature 
from ta02 t 
left join voucher v on t.t_key = v.v_key;


name
ta_over_amount
over_amount
signature


anh
100.00
50.00
white

anh
100.00
100.00
blue

duc
50.00
50.00
white

duc
50.00
100.00
blue

ho
25.00
25.00
green

ho
25.00
14.00
itsme

phi
15.00
25.00
green

phi
15.00
14.00
itsme


SELECT
    t.name,
    t.ta_over_amount,
    v.over_amount,
    v.signature
FROM ta02 t
JOIN voucher v
    ON v.v_key = t.t_key
WHERE
    t.ta_over_amount NOT IN
    (
        SELECT v2.over_amount
        FROM voucher v2
        WHERE
            v2.v_key = t.t_key
            AND v2.over_amount >= t.ta_over_amount
    );


name
ta_over_amount
over_amount
signature


phi
15.00
14.00
itsme

phi
15.00
25.00
green


SELECT
    t.name,
    t.ta_over_amount,
    v.over_amount,
    v.signature
FROM ta02 t
JOIN voucher v
    ON v.v_key = t.t_key
WHERE
    t.ta_over_amount NOT IN
    (
        SELECT v2.over_amount
        FROM voucher v2
        WHERE
            v2.v_key = t.t_key
            AND v2.over_amount >= t.ta_over_amount
    )
 AND t.ta_over_amount > v.over_amount;


name
ta_over_amount
over_amount
signature


phi
15.00
14.00
itsme
v_key	over_amount	signature
gogo	100.00	blue
gogo	50.00	white
logbasex	14.00	itsme
logbasex	25.00	green