openGauss每日一练第13天 | 学习openGauss导入数据

-- 1.
create table table1 (id int, name char(16));
insert into table1 values (1, 'abcdefg');
insert into table1 values (1, DEFAULT);
insert into table1 default values;
select * from table1;

-- 2.
create table table2 (id int, name char(16));
insert into table2 select * from table1;
select * from table2;

-- 3.
create table table3 (id int, name char(16));
insert into table3 values (1, 'abcdefg');
create table table4 (like table3);
insert into table4 values (2, 'asdfsdf');

merge into table3 t3
using table4 t4
on (t3.id = t4.id)
when matched then
update set t3.name = t4.name
when not matched then
insert values (t4.id, t4.name);

select * from table 3;

-- 4.
copy table3 to '/home/omm/table3.dat';
create table table5 (like table3);
copy table5 from '/home/omm/table3.dat';
select * from table5;

-- 5.
drop table table1;
drop table table2;
drop table table3;
drop table table4;
drop table table5;
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