SQL服务器将值分配给主键增量值

Question

I got two primary keys: 'ID' and 'last modified'.

ID is an identity which is incremental, that is, when I am adding a new row, it will be like:

    ID |       last modified       |value1|value2|value3|...|value_n|
    -- |---------------------------|------|------|------|---|-------|
     1 | 2011-10-01 13:03:00.000   |................................|
     2 | 2011-10-01 14:03:00.000   |................................|

Im adding those new rows from different tables, so I would like to update rows up to some conditions, and also, I would like to add new rows which refers to the same ID. I will give an example:

ID = 1, new row. ID = 2, new row.

Some conditions lead to insert a new row, which refer to the same ID (ID = 2), changing the last modified datetime too.

    ID |       last modified       |value1     |value2|value3|...|value_n|
    -- |---------------------------|------     |------|------|---|-------|
     1 | 2011-10-01 13:03:00.000   |................................     |
     2 | 2011-10-01 14:03:00.000   |old value..|.....................     |
     2 | 2011-10-01 15:03:00.000   |other value|.........................|

After that some conditions lead to update a row (referring to a particular ID, in this case, ID = 2), it will take the last modified time, and update it, and also update the last modified datetime:

    ID |       last modified       |value1   |value2|value3|...|value_n|
    -- |---------------------------|---------|------|------|---|-------|
     1 | 2011-10-01 13:03:00.000   |................................   |
     2 | 2011-10-01 14:03:00.000   |................................   |
     2 | 2011-10-01 16:03:00.000   |new value|.........................|

---

However, when I am adding a new row, even though I assign the same ID to the ID column, it is ignoring the assigning and it is increasing the ID, illustating this:

    ID |       last modified       |value1   |value2|value3|...|value_n|
    -- |---------------------------|---------|------|------|---|-------|
     1 | 2011-10-01 13:03:00.000   |................................   |
     2 | 2011-10-01 14:03:00.000   |................................   |
     3 | 2011-10-01 16:03:00.000   |.........|.........................|

I attach the code:

 IF (SELECT COUNT(*) FROM myTable WHERE myColumn = @myValue ) = 0 
     --change value
   BEGIN
        INSERT INTO myTable(ID, value1,value2...) VALUES (@ID, value1,value2..)
   END

However, and as I said, the assigning (ID = @ID) is not actually assingning because it is a PK is an autoincremental value and PK.

How can I make it right?? Any Ideas?

Answer 1

您需要将要插入值的表的标识插入设置为打开，然后再插入记录。

SET IDENTITY_INSERT YourTableName ON