Using tuples in SQL “IN” clause

拟墨画扇 提交于 2019-12-28 01:47:30

问题


I have a table containing the fields group_id and group_type and I want to query the table for all the records having any tuple (group id, group type) from a list of tuples. For example, I want to be able to do something like:

SELECT *
FROM mytable
WHERE (group_id, group_type) IN (("1234-567", 2), ("4321-765", 3), ("1111-222", 5))

A very similar question is already asked at: using tuples in sql in clause , but the solution proposed there presumes the tuple list is to be fetched from another table. This doesn't work in my case is the tuple values are hard coded.

One solution is to use string concatenation:

SELECT *
FROM mytable
WHERE group_id + STR(group_type, 1) IN ("1234-5672", "4321-7653", "1111-2225")

But the problem is that the table is quite big and doing a string concatenation and conversion for each record would be very expensive.

Any suggestion?


回答1:


Why not construct the OR statements?

SELECT *
FROM mytable 
WHERE (group_id = '1234-567' and group_type = 2)
    OR (group_id = '4321-765' and group_type = 3)
    OR (group_id = '1111-222' and group_type = 5)

Granted, it doesn't look as nice and neat as your concept example but it will do the job (and if you IN with tuples did exist, it would implement it exactly the same way under the covers most likely.




回答2:


Given a very minor tweak (replace double quotes with single and add the VALUES keyword), your proposed syntax is valid Standard SQL-92 syntax i.e.

SELECT *
  FROM mytable
 WHERE (group_id, group_type) IN (
                                  VALUES ('1234-567', 2), 
                                         ('4321-765', 3), 
                                         ('1111-222', 5)
                                 );

Sadly, MSFT have not added it to SQL Server and consider it an 'unplanned' feature.

FWIW PostgreSQL and Sqlite are examples of SQL products that support this syntax.




回答3:


In SQL Server 2008 you can do like this:

select *
from mytable as T
where exists (select *
              from (values ('1234-567', 2), 
                           ('4321-765', 3), 
                           ('1111-222', 5)) as V(group_id, group_type)
              where T.group_id = V.group_id and
                    T.group_type = V.group_type               
             )



回答4:


You can use a common table expression to pretend that these tuples are in another table:

;WITH Tuples as (
     select '1234-567' as group_id, 2 as group_type union all
     select '4321-765', 3 union all
     select '1111-222', 5
)
SELECT * /* TODO - Pick appropriate columns */
from mytable m where exists (
   select * from Tuples t
   where m.group_id = t.group_id and m.group_type = t.group_type)



回答5:


Using that solution, this should work:

SELECT *
FROM mytable m
WHERE EXISTS (
   SELECT * FROM (
   SELECT "1234-567" group_id, 2 group_type UNION ALL
   SELECT "4321-765", 3 UNION ALL
   SELECT "1111-222", 5) [t]
   WHERE m.group_id = t.group_id AND m.group_type = t.group_type) 

BTW, you should probably use a CTE to create that inner table.




回答6:


Here is another tuple solution using a join:

SELECT 
  *
FROM mytable m
JOIN
(
   SELECT "1234-567" group_id, 2 group_type 
   UNION ALL SELECT "4321-765", 3 
   UNION ALL SELECT "1111-222", 5
) [t]
ON m.group_id = t.group_id 
AND m.group_type = t.group_type



回答7:


I had a similar problem but my tuple collection was dynamic - it was sent over to the SQL Server in a query parameter. I came up with the following solution:

  1. Pass a tuple as an XML:

    DECLARE @tuplesXml xml = '<tuples><tuple group-id="1234-567" group-type="2"/><tuple group-id="4321-765" group-type="3"/></tuples>';
    
  2. Inner join the table that you want to filter with the XML nodes:

    SELECT t.* FROM mytable t
    INNER JOIN @tuplesXml.nodes('/tuples/tuple') AS tuple(col)
    ON tuple.col.value('./@group-id', 'varchar(255)') = t.group_id
    AND tuple.col.value('./@group-type', 'integer') = t.group_type
    

It seems to work fine in my situation which is a bit more complex than the one described in the question.

Keep in mind that it is necessary to use t.* instead of * and the table returned from nodes method needs to be aliased (it's tuple(col) in this case).




回答8:


select * from table_name where 1=1 and (column_a, column_b) in ((28,1),(25,1))


来源:https://stackoverflow.com/questions/8006901/using-tuples-in-sql-in-clause

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