[Webinar] Streamline your web hosting managementRegister Today

x
  • Status: Solved
  • Priority: Medium
  • Security: Public
  • Views: 591
  • Last Modified:

Using left outer join in SQL

select    table1.column_id,
             table1.column_type,
             table2.column_name
from     table1
left outer join table2
on         table1.column_type = table2.column_numb

In Table 1

column_id                  column_type
1                                     NULL
2                                      NULL
3                                     300


In Table 2

table2_column_id       column_numb   column_name
1                                  100                     ABC
2                                   200                    DEf
3                                  300                     GHI


Expected value

column_id                  column_type       column_name
1                                     NULL                 NULL
2                                      NULL                NULL
3                                     300                     GHI


My query is not picking the NULL Values. What could be the reason ??
0
chokka
Asked:
chokka
  • 2
  • 2
1 Solution
 
Eugene ZCommented:
looks good for me : see test code


check your tables datatype

use test 
go
create table  Table1 (column_id   int,               column_type int)

go
insert into Table1 
select 1 ,                                    NULL
union all select 2 ,                                     NULL
union all select 3 ,                                    300

go

create table  Table2 (table2_column_id  int,      column_numb int,  column_name varchar(50))

insert into table2
select 1 ,                                 100 ,                    'ABC'
union all select 2 ,                                  200 ,                   'DEf'
union all select 3    ,                              300 ,                    'GHI'

go
select    table1.column_id,
             table1.column_type,
             table2.column_name 
from     table1
left outer join table2
on         table1.column_type = table2.column_numb

Open in new window

0
 
chokkaAuthor Commented:
You say my query works fine. i actually mentioned the sample data.

i implemented same logic query in my production database, but records with null value is filtered.
0
 
Eugene ZCommented:
try the example that I posted
can you post data type for the columns in your table? or table structure?
0
 
chokkaAuthor Commented:
@Eugenez, Thanks !! My syntax is correct, but some conditional filtration filters the NULL Value column. Thank you for checking !!
0

Featured Post

Free Tool: Port Scanner

Check which ports are open to the outside world. Helps make sure that your firewall rules are working as intended.

One of a set of tools we are providing to everyone as a way of saying thank you for being a part of the community.

  • 2
  • 2
Tackle projects and never again get stuck behind a technical roadblock.
Join Now