create database test;
use test;

CREATE TABLE TEST (
group_name CHAR(2),
number1 DECIMAL(12, 2),
number2 DECIMAL(12, 2),
var varchar(1)
) ENGINE=COLUMNSTORE;

INSERT INTO TEST
SELECT CAST(ROUND(RAND() * 10, 0) AS CHAR),
ROUND(RAND() * 10000, 2),
ROUND(RAND() * 10, 2),
substring(MD5(RAND()),1,1)
FROM seq_1_to_6000000;

CREATE TABLE TEST2 (
group_name CHAR(2),
number1 DECIMAL(12, 2),
number2 DECIMAL(12, 2),
var varchar(1)
) ENGINE=COLUMNSTORE;

INSERT INTO TEST2
SELECT CAST(ROUND(RAND() * 10, 0) AS CHAR),
ROUND(RAND() * 10000, 2),
ROUND(RAND() * 10, 2),
substring(MD5(RAND()),1,1)
FROM seq_1_to_6000000;

CREATE TABLE TEST3 (
group_name CHAR(2),
number1 DECIMAL(12, 2),
number2 DECIMAL(12, 2),
var varchar(1)
) ENGINE=COLUMNSTORE;

INSERT INTO TEST3
SELECT CAST(ROUND(RAND() * 10, 0) AS CHAR),
ROUND(RAND() * 10000, 2),
ROUND(RAND() * 10, 2),
substring(MD5(RAND()),1,1)
FROM seq_1_to_6000000;

select * from TEST
inner join TEST2 on TEST2.var = TEST.var
inner join TEST3 on TEST3.number2 = TEST.number2;