问题描述
这里是我正在使用的密集设置的过度简化. table_1
和table_2
都具有自动增量代理主键作为ID. info
是一个包含有关table_1
和table_2
的信息的表.
Here is a gross oversimplification of an intense setup I am working with. table_1
and table_2
both have auto-increment surrogate primary keys as the ID. info
is a table that contains information about both table_1
and table_2
.
table_1 (id, field)
table_2 (id, field, field)
info ( ???, field)
我试图确定是否应该将info
的主键组合为table_1
和table_2
的ID.如果我要这样做,哪一个最有意义?
(在此示例中,我将ID 11209与ID 437组合在一起)
I am trying to decided if I should make the primary key of info
a composite of the IDs from table_1
and table_2
. If I were to do this, which of these makes most sense?
( in this example I am combining ID 11209 with ID 437 )
INT(9)
11209437 (我可以想象为什么这很糟糕) VARCHAR (10)
11209-437 DECIMAL (10,4)
11209.437
INT(9)
11209437 (i can imagine why this is bad)VARCHAR (10)
11209-437DECIMAL (10,4)
11209.437
还是其他?
将其用作MYSQL MYISAM DB上的主键是否可以?
Would this be fine to use this as the Primary Key on a MYSQL MYISAM DB?
推荐答案
我将使用复合(多列)键.
I would use a composite (multi-column) key.
CREATE TABLE INFO (
t1ID INT,
t2ID INT,
PRIMARY KEY (t1ID, t2ID)
)
这样,您还可以将t1ID和t2ID作为指向它们各自表的外键.
This way you can have t1ID and t2ID as foreign keys pointing to their respective tables as well.
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