InterSystems Cache

Question

SQL

Hello hackers!

By the will of fate, it happened that I work with the cache DBMS.
I dug up a bunch of manuals and I can’t find an analogue of the with command in DB2

. If someone tells me or gives a link to an explanatory manual on sql in cache? I would be very grateful.

Answer 1

documentation on Cache, this is the most complete one that can be found on Cache
documentation comes with Cache installed

Answer 2

and what exactly the with command does in DB2 - it will be easier to tell what its analogue in the porridge is.

Answer 3

There is definitely no such command, you can do it through a subquery of the form:

SELECT id
FROM
(	SELECT A as id
  FROM T1
  UNION ALL
  SELECT B as id
  FROM T2
)
ORDER BY id

In general, Cache` is not a relational DBMS, and you need to understand that any query comes down to bypassing globals. Build storage and indexes correctly and it will be fast.