SQL帮助，用于合并两个查询

Question

I want to combine these two SQL queries into one. Any idea on how do I do it?

Select A, B, C 
from table1 
where condition1


select D 
from table2 
where table1.B=table2.E 

(table2 has the mapping of column B of table1)

I just want to fetch A,B,C,D in a single select query. Any help would be appreciated.

Answer 1

INNER JOIN (read up on joins here http://www.w3schools.com/sql/sql_join.asp )

SELECT A, B, C, D
FROM table1 t1
INNER JOIN table2 t2 ON t1.B = t2.E
WHERE condition1

Answer 2

You could use a join :

select A, B, C, D
from table1 
left join table2
on table1.B = table2.E 
where condition1