postgresql COLLATE pg_catalog."default" 对 postgres 数据库表中的文本属性有什么作用？
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What does COLLATE pg_catalog."default" do on text attribute in postgres database table?
提问by Saurabh Bhatia
One of the fields while creating the table is described as below
创建表时的字段之一如下所述
id text COLLATE pg_catalog."default"
采纳答案by Michel Milezzi
It's just telling that you're using default lc_collatefor this column.
它只是告诉您正在lc_collate为此列使用默认值。
But what's the default collate? Use SHOWto discover that.
但是默认的整理是什么？使用SHOW来发现。
SHOW lc_collate;
PostgreSQL allows to create columns with different types of collation:
PostgreSQL 允许创建具有不同类型排序规则的列：
CREATE TABLE collate_test
(
default_collate text, --Default collation
custom_collate text COLLATE pg_catalog."C" --Custom collation
);
Did you see the difference?
你看到区别了吗？
More info about collation is on docs:
有关整理的更多信息在docs 上：
The collation feature allows specifying the sort order and character classification (...)
整理功能允许指定排序顺序和字符分类 (...)
