All tables in my database always have an id (autoincrement), at column 0 regardless of its name, it's always there.
So, in table teste I probably have idTeste, in table cars I should have idCars, but the format is not a standard, I could have a table example with a column simply called id.
I'm trying to create a generic update like:
update tablename set bla='ble' where column[0]='id';
so, don't matter the column's name, I wish to reference it by its id. Is that possible?
I know I can do something like:
show columns from table
and pick the first name before execute my update, and, in fact, I did that to solve my problem, but I'm curious if it was possible.
What you're after is called the ordinal position, or simply "ordinal".
SQL does not support using ordinals in the WHERE clause. Support for ordinals differs between database vendors -- the most common support is in the ORDER BY clause:
ORDER BY 2, 1
...which relies on the column(s) listed in the SELECT clause. Some support ordinals in the GROUP BY clause.
That said, using ordinals is not a recommended practice because it's dependent on the order of the columns in the SELECT clause. If that order changes without the ORDER BY/etc being updated, you won't know until runtime.