If nothing else, anyone needing MERGE can port their MERGE statements to
a DML with DML-containing CTEs...
The generic mapping would be something like this, I think:
WITH
rows AS (SELECT <target> FROM <target> WHERE <condition>)
, updated AS (
UPDATE <target>
SET ...
WHERE <key> IN (SELECT <key> FROM rows) /* matched */
RETURNING <target>
)
, inserted AS (
INSERT INTO <target>
SELECT ...
WHERE <key> NOT IN (SELECT <key> FROM rows) /* not matched */
RETURNING <target>
)
DELETE FROM <target>
WHERE (...) AND
<key> NOT IN (SELECT <key> FROM updated UNION
SELECT <key> FROM inserted);
Nico
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