Create an inline SQL table on the fly (for an excluding left join)

问题

Let's assume the following:

Table A

id | value
----------
1   | red
2   | orange
5   | yellow
10  | green
11  | blue
12  | indigo
20  | violet

I have a list of id's (10, 11, 12, 13, 14) that can be used to look up id's in this table. This list of id's is generated in my frontend.

Using purely SQL, I need to select the id's from this list (10, 11, 12, 13, 14) that do not have entries in Table A (joining on the 'id' column). The result should be the resultset of id's 13 and 14.

How can I accomplish this using only SQL? (Also, I'd like to avoid using a stored procedure if possible)

The only approach I can think of is something that would create an inline SQL table on the fly to temporarily hold my list of id's. However, I have no idea how to do this. Is this possible? Is there a better way?

Thanks! :)

回答1:

You can create an "inline table" with a UNION subquery:

(
            SELECT 10 AS id
  UNION ALL SELECT 11 UNION ALL SELECT 12 UNION ALL SELECT 13 UNION ALL SELECT 14
  -- etc.
) AS inline_table

回答2:

You can do this from SQL Server 2008 onwards using a table value constructor.

SELECT * FROM (
   VALUES(1, 'red'),
         (2, 'orange'),
         (5, 'yellow'),
         (10, 'green'),
         (11, 'blue'),
         (12, 'indigo'),
         (20, 'violet'))
   AS Colors(Id, Value)

More information here: Table Value Constructor

回答3:

CREATE TEMPORARY TABLE ids (id INT NOT NULL PRIMARY KEY);

INSERT
INTO    ids
VALUES
(10),
(11),
(12),
(13),
(14);

SELECT  *
FROM    ids
WHERE   id NOT IN
        (
        SELECT  id
        FROM    a
        );

回答4:

create table B (id int)
insert into B values (10),(11),(12),(13),(14)

select *
from B
left join A 
on A.id=B.id
where A.id is null

drop table B

http://sqlfiddle.com/#!6/6666c1/30

来源：https://stackoverflow.com/questions/10709464/create-an-inline-sql-table-on-the-fly-for-an-excluding-left-join

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