Select a non existing column in mysql

Question

Is it possible say for example i want to select a column which does not exist in an mysql table, i just want this column to have incremental values starting from "somevalue (100 maybe)". I want something like this:

my dummy column | other existing columns | blah
100
101
102

is this possible in mysql?

Answer 1

Yes sure, You can named column with as keyword. For example:

SELECT 1 as 'hello'

And You can simply add RowNumber column like below example:

SELECT t.*, 
    @rownum := @rownum + 1 as RowNumber
FROM your_table t, 
     (SELECT @rownum := 0) r

For start from 149, You just need to replace (SELECT @rownum := 0) with (SELECT @rownum := 149)

For a dummy column with the certain type, Use Cast or Convert functions like this: CAST(@rownum := @rownum + 1 AS CHAR) AS RowNumber. You can find more about this here: http://dev.mysql.com/doc/refman/5.0/en/cast-functions.html

More Examples related to the comments:

SELECT
    COUNT(col1) AS col2
FROM your_table
GROUP BY col2
HAVING col2 = 2;

@nodsdorf example in the comments:

SELECT
    (1+1) AS dummy,
    other_column
FROM table