How to fill null with value from the previous line?

Question

How to fill null with value from the previous line?

Navigation

#1 by (2 votes)

2

Looking at the following table, I want to fill in the value that is null with the value of the previous line, what is the best thing to do with mysql?

mysql query

asked by anonymous 21.10.2015 / 16:03

1 answer

Double Error Message Javascript Ajax How to restrict access to a particular page in the admin panel. of wordpress?

score 2 · Answer 1

Considering that the rows are ordered by column header1, and that this column is numeric and sequential (no numbering holes):

select  cabecalho1, cabecalho2, 
        novoresultado = isnull(cabecalho2,(select cabecalho2 from yourTable where cabecalho1= t.cabecalho1-1))
from yourTable t

--update
update yourTable
set novoresultado = isnull(cabecalho2,(select cabecalho2 from yourTable t where t.cabecalho1 = yourTable.cabecalho1-1))

Considering that the rows are ordered by column header1, and that this column is numeric, but with the possibility of missing numbers in the sequence:

select  cabecalho1, cabecalho2, 
        novoresultado = isnull(cabecalho2,(select top 1 cabecalho2 from yourTable where cabecalho1 < t.cabecalho1 order by cabecalho1 desc))
from yourTable t

--update
update yourTable
set novoresultado = isnull(cabecalho2,(select top 1 cabecalho2 from yourTable t where t.cabecalho1 < yourTable.cabecalho1 order by cabecalho1 desc))