check 制約。

check.sql

create table t (a int check(a > 5));
insert into t values (1); -- Error: CHECK constraint failed: t
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create table a(x int);
insert into a values ('hoge');
insert into a values (5);
select * from a; -- hoge 5
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create table b(x int check(typeof(x) is 'integer'));
insert into b values ('hoge'); -- Error: CHECK constraint failed
insert into b values (5);
select * from b; -- 5