SELECT DISTINCT values and INSERT INTO table

Question

I want to take a column with values that repeat multiple times and get that value only once and store it for later use, but at the same time I would like to get another value in the same row as that distinct column.

A      B       C
32263  123456  44
32263  123456  45
32263  123456  46
32264  246802  44
32263  246802  45
32264  246802  46
32265  369258  44
32265  369258  45
32265  369258  46

A, B, C represent three columns. Ignore C for now.

My question is: How can I get this information in this table and store it for I can use it later in the script?

Here is what I tried:

use databaseName

select distinct A from tableName
order by A

The result is:

A
32263
32264
32265

I'm trying to get it to also give me B's value. (Note it does not matter at all which row I get since no matter what A I choose the value of B will be the same for given A.) We are ignoring C for now.

The result should be:

A      B
32263  123456
32264  246802
32265  369258

Now, once I get it like that I want to insert a row using the values I got from the query. This is where C comes in. I want to do something like this:

use databaseName

insert into tableName (A, B, C)
values (32263, 123456, 47)

Of course I don't want to put the values directly inside of there, instead have some type of loop that will cycle through each of the 3 distinct A values I found.

In short, my table should go from:

A      B       C
32263  123456  44
32263  123456  45
32263  123456  46
32264  246802  44
32263  246802  45
32264  246802  46
32265  369258  44
32265  369258  45
32265  369258  46

To:

A      B       C
32263  123456  44
32263  123456  45
32263  123456  46
32263  123456  47 -
32264  246802  44
32263  246802  45
32264  246802  46
32264  246802  47 -
32265  369258  44
32265  369258  45
32265  369258  46
32265  369258  47 -

I placed dashes next to the newly added rows to help you see the changes.

I figure I should perhaps do some type of loop that will cycle through all three distinct A values, but my problem is how to do that?

Thanks for your time.

Answer 1

You can use INSERT INTO... SELECT statement on this,

INSERT INTO tableName (A, B, C)
SELECT A, B, MAX(C) + 1
FROM tableName
GROUP BY A, B

• SQLFiddle Demo

Answer 2

Try this:

SELECT * INTO new_table FROM
   (SELECT DISTINCT * FROM table_name) x