how to write a join query between two tables

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Hi I have data like this

Table 1 has following data

SQL

sno name 
1    a
2    b 
3    c
4    d
5    e

Table 2 has following data

SQL

sno name
1   b
2   a
3   c
4   d
6   f

now how can i write a query that if name in both the tables are equal the it has to get sno of table2 else get sno of table1 and along with this the join query should return all the rows in both Table 1 and Table2

Posted 30-Nov-14 22:48pm

lakshmichawala

Updated 30-Nov-14 22:52pm

King Fisher

v2

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Shweta N Mishra · Answer 1 · 2014-11-30T23:01:00

Solution 1

Check this
SQL Joins - W3Schools[^]

Also this may help you

SQL

select isnull(b.sno,a,sno),a.*,b.* 
from table1 a Full Outer Join table2 on a.name=b.name

Posted 30-Nov-14 23:01pm

Shweta N Mishra

Maciej Los · Answer 2 · 2014-12-01T00:58:00

This query should return all records with equal names:

SQL

SELECT COALESCE(t2.sno, t1.sno) AS NewSno, t2.name
FROM table1 AS t1 INNER JOIN table2 as t2 ON t1.name = t2.name

For further information about different types of joins, please read this: Visual Representation of SQL Joins[^]
COALESCE[^]

/\jmot · Answer 3 · 2014-12-01T09:40:00

see this..

SQL

select
(case when a.name=b.name then isnull(b.sno,a.sno) else isnull(a.sno,b.sno) end) as sno ,
isnull(a.name,b.name) from [dbo].[Table_1] a

full join

[dbo].[Table_2] b on a.sno=b.sno

Here http://stackoverflow.com/questions/18828641/sql-difference-between-coalesce-and-isnull[^]

Chandra Mohan N · Answer 4 · 2014-12-02T01:19:00

Solution 4

Check this link

Visual Representation of SQL Joins[^]

Posted 2-Dec-14 1:19am

Chandra Mohan N

how to write a join query between two tables

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