Need to solve this problem, substring('PA-1501200', 4 , 99), sql thinks its a date

[Sl1ver]

i got this

substring('PA-1501200', 4 , 99)

now for some reason i think it sees the number as a date, it should be n varchar and then convert it into a int, then i get this error

Conversion failed when converting datetime from character string.

and here is my sql
the ponumber will be the same as the grid number if i get it to work

declare @PONumber varchar(50)
declare @GridNumber varchar(50)


--set @PONumber = 
set @GridNumber = substring('PA-1501200', 4 , 99)

select * from int_err_PutAway_writeback
where 
((refno = @PONumber) and isnull(@PONumber,'') <> '')
or
((refno = @GridNumber) and isnull(@PONumber,'') = '')
and err_datetime is not null
union all
select *, ' ' ab_res from int_err_Receive_writeback
where 
((refno = @PONumber) and isnull(@PONumber,'') <> '')
or
((refno = @GridNumber) and isnull(@PONumber,'') = '')
and err_datetime is not null
union all
select * from int_err_ibtPutAway_writeback
where 
((refno = @PONumber) and isnull(@PONumber,'') <> '')
or
((refno = @GridNumber) and isnull(@PONumber,'') = '')
and err_datetime is not null
union all
select *, ' ' ab_res from int_err_ibtReceive_writeback
where 
((refno = @PONumber) and isnull(@PONumber,'') <> '')
or
((refno = @GridNumber) and isnull(@PONumber,'') = '')
and err_datetime is not null
order by err_datetime desc

[ck9663]

Here are the possible reason for your error:

1. If your code passes the line

   set @GridNumber = substring('PA-1501200', 4 , 99)

then the error is on your select.

2.Your REFNO column is a date data type.

3. One of the field on your table that you're trying to UNIONize is a date and you're trying to UNION it with a char/varchar column.

Happy Coding!!!

~~ CK