基于一个视图连接两个表，sql

Question

I have the following sql situation

Table1
 id name

Table2
 id name

_Table1ToTable2
 id, id_table1, id_table2

Result:
 id, name, table2_name, table2_id

I would like to join Table1 and Table2 into a single query, but I cannot find a way to make a join between them, any ideas?

Answer 1

if there is no relationship between table1 and table 2 then,

select table1.id, table1.name, table2.id, table2.name from
table1, table2

if table1 and table2 are related with ID then,

select  table1.id, table1.name, table2.id, table2.name from
table1
inner join table2
  on table1.id = table2.id

Answer 2

If your intention is to retrieve a result set with every possible combination of the id columns from both tables then you can do as follows:

select id = identity (int, 1, 1), * into #a from (select distinct table1. id as id1, table2. id as id2 from table1 cross apply table2) d; select * from #a; drop table #a

If you do not wish to use a temp table an alternative would be to use some variation of the row_number() function.

The above solves for an assumed requirement as your question lacks context. Elaborate on your requirements and we will be able to provide you with a more relevant and detailed answer.

Answer 3

It seems like you want to use bridge table Table1ToTable2 to join Table1 and Table2 . This can be done simply with 2 INNER JOIN s :

SELECT
    tt.id AS tt_id,
    t1.id AS t1_id,
    t1.name AS t1_name,
    t2.id AS t2_id,
    t2.name AS t2_name
FROM
    Table1ToTable2 AS tt
    INNER JOIN Table1 AS t1
        ON t1.id = tt.id_table1
    INNER JOIN Table2 AS t2
        ON t2.id = tt.id_table2