插入和更新

插入和更新的全局唯一性保证

在全局唯一索引创建过程中，系统会对所有现有分区执行索引扫描，如果在其他分区而不是当前分区中发现重复项，则会引发错误。

示例

命令

create table gidx_part (a int, b int, c text) partition by range (a);
create table gidxpart (a int, b int, c text) partition by range (a);
create table gidxpart1 partition of gidxpart for values from (0) to (10);
create table gidxpart2 partition of gidxpart for values from (10) to (100);
create unique index gidx_u on gidxpart using btree(b) global;

insert into gidxpart values (1, 1, 'first');
insert into gidxpart values (11, 11, 'eleventh');
insert into gidxpart values (2, 11, 'duplicated (b)=(11) on other partition');

输出

ERROR:  duplicate key value violates unique constraint "gidxpart2_b_idx"
DETAIL:  Key (b)=(11) already exists.