Postgres 15

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CREATE TABLE monthlysales (

gal text NOT NULL,

m1 integer,

m2 integer,

m3 integer,

m4 integer,

m5 integer,

m6 integer,

m7 integer,

m8 integer,

m9 integer,

m10 integer,

m11 integer,

m12 integer

);

INSERT INTO monthlysales (gal, m1, m2, m3, m4, m5, m6, m7, m8, m9, m10, m11, m12) VALUES ('小島南', 5632, 3508, 4767, 2976, 10722, 3256, 8357, 1094, 3617, 6523, 5731, 8747);

INSERT INTO monthlysales (gal, m1, m2, m3, m4, m5, m6, m7, m8, m9, m10, m11, m12) VALUES ('佐山愛', 3234, 10219, 8861, 9389, 9835, 8251, 5770, 10341, 10624, 6875, 3426, 2937);

INSERT INTO monthlysales (gal, m1, m2, m3, m4, m5, m6, m7, m8, m9, m10, m11, m12) VALUES ('小花暖', 8219, 5467, 4453, 1839, 10604, 10174, 6401, 5775, 1203, 10334, 9901, 3890);

select * from monthlysales;

CREATE TABLE

INSERT 0 1

INSERT 0 1

INSERT 0 1

gal	m1	m2	m3	m4	m5	m6	m7	m8	m9	m10	m11	m12
小島南	5632	3508	4767	2976	10722	3256	8357	1094	3617	6523	5731	8747
佐山愛	3234	10219	8861	9389	9835	8251	5770	10341	10624	6875	3426	2937
小花暖	8219	5467	4453	1839	10604	10174	6401	5775	1203	10334	9901	3890

SELECT 3

select gal

, greatest(m1,m2,m3,m4,m5,m6,m7,m8,m9,m10,m11,m12)

from monthlysales;

gal	greatest
小島南	10722
佐山愛	10624
小花暖	10604

SELECT 3