SQL Server 2014 In-Memory OLTP | TechDays Sweden 2014Johan Åhlén
Presentation (in Swedish) from Microsoft TechDays Sweden 2014.
For more information (in Swedish) see http://www.johanahlen.info/2014/11/sql-server-2014-in-memory-oltp-eller-what-the-heck-is-a-hekaton/.
SQL Server 2014 In-Memory OLTP | TechDays Sweden 2014Johan Åhlén
Presentation (in Swedish) from Microsoft TechDays Sweden 2014.
For more information (in Swedish) see http://www.johanahlen.info/2014/11/sql-server-2014-in-memory-oltp-eller-what-the-heck-is-a-hekaton/.
Slides in swedish from a presentation I held at Valtech Days 2009 on the architecture of the web. I discus HTTP, resource and service application design.
Revitalisering av legacy - är det möjligt - Joakim LindbomJoakim Lindbom
How do you put old or almost dead systems in a state where you can handle and further develop them another 10 years? This seminar is discussing the need for modernisation in a digital age and 6 project experiences, both good and bad.
Slides in swedish from a presentation I held at Valtech Days 2009 on the architecture of the web. I discus HTTP, resource and service application design.
Revitalisering av legacy - är det möjligt - Joakim LindbomJoakim Lindbom
How do you put old or almost dead systems in a state where you can handle and further develop them another 10 years? This seminar is discussing the need for modernisation in a digital age and 6 project experiences, both good and bad.
5. Vad göra?
• Relaxa hårda strukturkrav som ställs av
relationela databaser
• Ge upp idén om datastrukturens abstraktion
från applikationens behov
• Flytta ansvar för struktur och
integritetskontroll till front-end
6.
7. Key-value stores Columnar DBs Document DBs
mindre struktur, enklare API mer struktur, rikare API
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13. Från detta kan vi bl a se att:
• Relationsdatabaser är overkill för data som
kan effektivt representeras som key-value. De
är underkill när data är komplext strukturerat
och kontextrik.
• Med overkill tappar du i skalbarhet
• Med underkill tappar du i prestanda
15. ACID
• Atomic: Everything in a transaction succeeds
or the entire transaction is rolled back.
• Consistent: A transaction cannot leave the
database in an inconsistent state.
• Isolated: Transactions cannot interfere with
each other.
• Durable: Completed transactions persist, even
when servers restart etc.
16. BASE
An alternative to ACID is BASE:
• Basic Availability
• Soft-state
• Eventual consistency
Rather than requiring consistency after every
transaction, it is enough for the database to eventually
be in a consistent state. (Accounting systems do this all
the time. It’s called “closing out the books.”) It’s OK to
use stale data, and it’s OK to give approximate answers.
17. ACID (RDBMS) vs BASE (de mest extrema NoSQLDb:s)
Det finns ingen kamp egentligen.
1. Det är ett kontinuum mellan BASE och ; dina
behov bestämmer
2. Buzzword är Polyglot Persistence: olika DB:s
för olika uppgifter inom ramen för lösningen.