Replacing set of rows with another set in sqlite - sql

Question

I've a table values with columns like this:
id: integer primary key
value: varchar(128)
type_id: integer (foreign key)
owner_id: integer (foreign key)
and some sample data:
id value type_id owner_id
...
5 aaa 0 1
6 bbb 0 2 // Rows
7 ccc 1 2 // to
8 ddd 1 2 // be
9 eee 2 2 // replaced
10 fff 0 3
...
Now I would like to replace all rows where owner_id == 2 with a new set of data. Simple approach is to DELETE all rows for owner_id == 2 and INSERT new ones. However I wonder if there is another solution?
In my case:
New set may contain exactly the same data (no action needed).
Or it could contain the same data but one row (deletion needed). Example: no more bbb with type_id == 0
Or there is one more row (insertion needed). Example: bbb, ccc, ddd and eee with exactly the same values for type_id plus ggg with type_id = 1
Or one of the values in values column changed (update needed). Example: exactly the same data but instead of ccc with type_id == 1 there is ggg with type_id == 1
It can be also any combination of operations above.
The reason I try to avoid DELETE + INSERT that I'll have many such updates and with such approach id will start growing fast.

Answer 1

As you don't seem to be around to respond to comments, let's get started.
In line with my above comments, I did iron out (what appears to me as) some wrinkles:
in your request: "no more bbb with type_id == 1" - which is not part of your sample data - going for type_id 0), and
your sample data: (values "ccc" and "ddd" for type_id 1 and owner_id - going for unique owner_id type_id combinations).
If applicable, you might enforce the latter by:
CREATE UNIQUE INDEX ValuesTable_TypeOwner ON ValuesTable(owner_id, type_id);
NB: I changed the tablename as VALUES is a SQL reserved word.
You might want to try along (pulling the to be applied modifications from a table called Changes):
Delete no longer existing owner_id type_id combinations:
WITH
To_Delete (id) AS (
SELECT
id
FROM ValuesTable V
JOIN Changes C
ON V.owner_id = C.owner_id
AND V.type_id
NOT IN (SELECT type_id
FROM Changes
WHERE owner_id = C.owner_id)
)
DELETE FROM ValuesTable
WHERE id IN (SELECT id FROM To_Delete)
;
Update deviating values:
WITH
To_Update (id) AS (
SELECT
id
FROM ValuesTable V
JOIN Changes C
ON V.owner_id = C.owner_id
AND V.type_id = C.type_id
AND V.value <> C.value
)
UPDATE ValuesTable
SET value = (SELECT value
FROM Changes
WHERE ValuesTable.owner_id = owner_id
AND ValuesTable.type_id = type_id
)
WHERE id IN (SELECT id FROM To_Update)
;
Insert new owner_id type_id combinations:
WITH
To_Insert (value, type_id, owner_id) AS (
SELECT
value
, type_id
, owner_id
FROM Changes
WHERE NOT EXISTS
(SELECT 1
FROM ValuesTable
WHERE Changes.owner_id = owner_id
AND Changes.type_id = type_id
)
)
INSERT INTO ValuesTable (value, type_id, owner_id)
SELECT value, type_id, owner_id FROM To_Insert
;
Starting from
ValuesTable Changes
| id | value | type_id | owner_id | | value | type_id | owner_id |
|----|-------|---------|----------| |-------|---------|----------|
| 5 | aaa | 0 | 1 | | ccc | 1 | 2 |
| 6 | bbb | 0 | 2 | | ddd | 2 | 2 |
| 7 | ccc | 1 | 2 | | xxx | 3 | 2 |
| 8 | ddd | 2 | 2 | | yyy | 4 | 2 |
| 9 | eee | 3 | 2 |
| 10 | fff | 0 | 3 |
it returns:
| id | value | type_id | owner_id |
|----|-------|---------|----------|
| 5 | aaa | 0 | 1 |
| 7 | ccc | 1 | 2 |
| 8 | ddd | 2 | 2 |
| 9 | xxx | 3 | 2 |
| 11 | yyy | 4 | 2 |
| 10 | fff | 0 | 3 |
See it in action: SQL Fiddle.
NB: Instead of using a Changes table, the WITH clause could, of course, be extended accordingly.
Please comment if and as this requires adjustment / further detail.