问题描述
在pgsql中，有没有一种方法可以建立包含多个值的表，并选择其中一个值（例如other_id），找出其最大值，然后使表中每个新条目都从该值开始递增值。
In pgsql, is there a way to have a table of several values, and choose one of them (say, other_id), find out what its highest value is and make every new entry that is put in the table increment from that value.
我想这太容易了，不可能有工作的机会。
I suppose this was just too easy to have had a chance of working..
ALTER TABLE address ALTER COLUMN new_id TYPE SERIAL
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ERROR: type "serial" does not exist
非常感谢您提供任何见解！
Thanks much for any insight!
推荐答案
快速浏览在告诉您
t使现有（整数）列用作序列，只需手动创建序列（名称是任意的），并将其当前值设置为当前的最大值（或更大） address.new_id 值，将其设置为 address.new_id 列的默认值。
If you want to make an existing (integer) column to work as a "serial", just create the sequence by hand (the name is arbitrary), set its current value to the maximum (or bigger) of your current address.new_id value, at set it as default value for your address.new_id column.
要设置序列的值，请参见。
To set the value of your sequence see here.
SELECT setval（'address_new_id_seq'，10000）;
这只是一个示例，使用您自己的序列名称（任意，您可以创建它），并且其数字大于列的当前最大值。
This is just an example, use your own sequence name (arbitrary, you create it), and a number greater than the maximum current value of your column.
更新：正如卢卡斯的答案所指出的（应该是接受的），您还应该使用来指定序列属于到哪一列创建/更改序列...拥有者...
Update: as pointed out by Lucas' answer (which should be the acccepted one) you should also specify to which column the sequence "belongs to" by using CREATE/ALTER SEQUENCE ... OWNED BY ...
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