matc

4 ms·

1.
by matc 15y ago
> The application can move straight to supporting the new structure and entirely forget that the old one existed. Not always. Changing the schema can break an application, in particular when the database supports multiple applications
2.
by matc 15y ago
The fact that ALTER TABLE locks on most databases is not the primary reason changing a schema is hard. The primary reason is that a schema change breaks the application [1]. Migrations are programs, but your existing live application is als
3.
by matc 15y ago
Moving databases between clusters is no easy feat. Can you share more details on the man-hours it took to oversee and verify the migration? I see you mention several days for the data to be copied, but how about the time to put your solutio
4.
ChronicDB launches database metadata API(chronicdb.com)
1 points by matc 15y ago|0 comments
5.
by matc 15y ago
You can easily drop the oldest month every 1st using a delete statement. Queries can be fast with indexes without adding complexity.
6.
Ask HN: Databases have indexes. Then why have partitions?
2 points by matc 15y ago|4 comments
7.
by matc 15y ago
If you are up for SQL, the downtime issue is solvable with ChronicDB pain-free.
8.
by matc 15y ago
1. Thank you for the link on views being updateable with some (natural) restrictions ( http://news.ycombinator.com/item?id=3406952 ). Given this feature, SQL offers the primitives needed. Even if this feature is missing from various databas
9.
by matc 15y ago
You are right, this aspect is not new. More like half-baked. I'm not sure what you mean by bidirectional. If this suggests having a separate copy for the old data and the new data then, in ChronicDB at least, no they are not bidirectional.
10.
by matc 15y ago
If you change the schema then the old version of the app can break. For example, if two tables are merged together. If one suggests old data and new data be stored separately then the door to data inconsistency opens.
11.
by matc 15y ago
Views are the reflection of the light at the end of the tunnel, but solve less than half the problem to date. Views work on SELECT, but not on UPDATE/INSERT/DELETE. Also, what makes you say that database as an integration layer should alway
12.
by matc 15y ago
This is what you are missing: > but that is always true You may have an old form you can't change. For example: - 10 apps connected to the same database. Changing the model breaks 10 apps. And you may not have access to change the cod
13.
by matc 15y ago
Schema-free != handling data model changes transparently.
14.
by matc 15y ago
We are actually working on this at ChronicDB http://chronicdb.com On 6ren's rigidity argument, relations and SQL are still not enough to guarantee you'll always be able to get the data you need; notably, when the data model changes. Backw
15.
by matc 15y ago
Agreed on backwards compatible, but for application semantics; not types of schema changes. There's no reason to not be allowed to both add and remove a column at the same time, or to merge and split whole tables. In your example, these k
16.
by matc 15y ago
Why not?
17.
by matc 15y ago
There is no efficient safety interlock system when modifying data. Even if confident your test passed, what happens when you later realize it hadn't, and at what cost?
18.
by matc 15y ago
The denormalization argument is misguided. Denormalization is a performance consideration, and now even happens transparently at the storage layer in some RDBMs. So restructuring a 'live' database should be done for semantic reasons: becaus
19.
Rate our startup: Git for databases(chronicdb.com)
15 points by matc 15y ago|4 comments
20.
UNDELETE FROM Whoops;(chronicdb.com)
6 points by matc 15y ago|0 comments
21.
by matc 15y ago
Why isn't the CAN-SPAM act enforced, say in the US?
22.
Ask HN: How would you make Twitter irrelevant?
8 points by matc 15y ago|7 comments
23.
by matc 15y ago
Would it be impossible to make email spam illegal? Why was it possible to make SMS spam, but not email, illegal?
24.
by matc 15y ago
There are email gateways to all major phone providers, so one can send, rather than receive, text messages without cost.
25.
Ask HN: Why don't we get spam on cell phones?
1 points by matc 15y ago|7 comments
26.
How To Hot-Move An SQL Database(chronicdb.com)
3 points by matc 15y ago|0 comments
27.
How To Hot-Move An SQL Database(chronicdb.com)
2 points by matc 15y ago|0 comments
28.
Most Important Factor In Entrepreneurial Success (It's Not Politics)(ccsenet.org)
1 points by matc 15y ago|0 comments