为什么看不到表的列名？ [英] Why can't I see the column names of a table?

问题描述

所以我以编程方式制作了一些表，我想验证它的结构是否符合我的想法。

So I made some tables programatically and I want to verify it's structure is what I think it is.

>Rocko=# \c Rocko
Password for user Rocko:
psql (8.4.4, server 8.4.8)
You are now connected to database "Rocko".
Rocko=# \d
            List of relations
 Schema |     Name     |   Type   | Owner
--------+--------------+----------+-------
 public | Email        | table    | Rocko
 public | Email_id_seq | sequence | Rocko
 public | Test         | table    | Rocko
 public | Test_id_seq  | sequence | Rocko
 public | User         | table    | Rocko
 public | User_id_seq  | sequence | Rocko
(6 rows)

因此，例如，我想查看测试。

So, for example, I want to see the columns in Test.

Rocko =＃\d测试

没有找到任何名为 Test的关系。

等一下？！测试不是只显示在关系列表下吗？

Wait a minute?! Did not Test just show up under "List of Relations"? What's going on here?

推荐答案

PostgreSQL默认将未加引号的标识符（例如表名和列名）转换为小写。该标准说，标识符应该规范化为大写，但这在这里并不重要。因此，当您这样说：

PostgreSQL converts unquoted identifiers (such as table and column names) to lower case by default; the standard says that identifiers are supposed to be normalized to upper case but that's not important here. So, when you say this:

\d Test

PostgreSQL认为与 \d测试相同。您可能有一个用引号引起来的表：

PostgreSQL considers that the same as \d test. You probably have a table that was created with a quoted name:

create table "Test" ( ...

，以便其名称区分大小写，并且每次引用时都必须用双引号引起来。因此，请尝试使用引号名称：

so that its name is case sensitive and must be quoted (with double quotes) every time it is referenced. So try quoting the name:

\d "Test"

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