Select query for particular column value

Question

I have two tables like the following. How can I query this to join these two tables? I need to implement this in one query.

Table1

 Id  name mark     
---  ---- ----   
1   name1 40    
2   name2 30   
3   name3 20  
4   name4 80 

Table2

details_id    address userid  
----------    ------- ---
 1            A1      user=2
 2            dd      user=3
 3            gg      user=1
 4            kk      user=4

I need to join these tables using id and userid in both tables.

select * from table1 left join table2 on table1.id = table2.userid

Answer 1

Try something like this:

SELECT* 
FROM table1 
    LEFT JOIN table2 
        ON 'user=' + CAST(table1.id AS char(10)) = table2.userid

Alternatively, you could use a substring or something similar to remove the 'user=' and cast it as an integer for the join.