openGauss每日一练第21天 | 学习openGauss存储模型-行存和列存

1.创建行存表和列存表，并批量插入10万条数据(行存表和列存表数据相同)

CREATE TABLE test_row
(
col1 CHAR(2),
col2 VARCHAR2(40),
col3 NUMBER
);


insert into test_row select col1, col2, col3 from (select generate_series(1, 100000) as key, repeat(chr(int4(random() * 26) + 65), 2) as  col1, repeat(chr(int4(random() * 26) + 65), 30) as  col2, (random() * (10^4))::integer as col3);

CREATE TABLE test_column
(
col1 CHAR(2),
col2 VARCHAR2(40),
col3 NUMBER
)
WITH (ORIENTATION = COLUMN);

insert into test_column select * from test_row;

2.对比行存表和列存表空间大小

\d+

3.对比查询一列和插入一行的速度

analyze VERBOSE test_row;
analyze VERBOSE test_column;
explain analyze select distinct col1 from test_row;
explain analyze select distinct col1 from test_column;

explain analyze insert into test_row values('x', 'xxxx', '123');
explain analyze insert into test_column values('x', 'xxxx', '123');

4.清理数据

drop table test_row;
drop table test_column;