MySQL将注释添加到外键 [英] MySQL Adding COMMENT to a Foreign Key

问题描述

我正在将一个旧的数据库SyBase转换为MySQL，并且我有这个DDL查询:

I'm translating an old database SyBase to MySQL and I have this DDL Query:

ALTER TABLE "DBA"."tab_prodotto"
  ADD FOREIGN KEY "fkey_idlinea" ("tpr_idlin") 
  REFERENCES "DBA"."linea" ("lin_id")
go
COMMENT ON FOREIGN KEY "DBA"."tab_prodotto"."fkey_idlinea" IS
'Riferimento linea'
go

查询的Alter部分工作良好，但是我在COMMENT上遇到了麻烦.我已经知道可以更改添加COMMENT的列，但是外键也可以吗?如果是，怎么办?我在文档上没有发现任何特别之处.预先谢谢你.

The Alter part of query works well, but I have troubles on COMMENT. I already know that I can alter a column for adding a COMMENT, but is that possible for foreign keys too? If yes, how? I haven't find nothing special on documentation. Thank you in advance.

推荐答案

The MySQL reference manual shows the allowed syntax for the FOREIGN KEY command to be:

  [CONSTRAINT [symbol]] FOREIGN KEY
  [index_name] (index_col_name, ...)
  REFERENCES tbl_name (index_col_name,...)
  [ON DELETE reference_option]
  [ON UPDATE reference_option]

reference_option:
   RESTRICT | CASCADE | SET NULL | NO ACTION

没有允许的 COMMENT 部分.看来这是不允许的.

There is no allowable COMMENT section. It looks like this is not allowed.

我上面引用的手册来自5.6版.我检查了5.1和5.5版本，语法是一样的.

The manual I referenced above is from version 5.6. I checked versions 5.1 and 5.5 and the syntax is the same.

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