In-memory

What that in-memory term is about, and what not

Everybody is talking about in-memory databases these days. And everybody is talking about columnar store for sets of data because this can be a benefit for analytic queries. And a lot of people start mixing these terms not realizing that(…)

Row Store vs Column Store in SAP HANA

The SAP HANA database allows you to create your tables in Row or Column Store mode. In this blog, I will demonstrate that each method has its advantages and disadvantages and should be used for specific cases. Thanks to two(…)

Variations on 1M rows insert (3): using SQL Server In-Memory features

Let’s continue with this series about inserting 1M rows and let’s perform the same test with a new variation by using SQL Server In-Memory features. For this blog post, I will still use a minimal configuration that consists of only(…)

Variations on 1M rows insert (4): IN MEMORY

By Franck Pachot . Oracle In-Memory option is for reporting. Oracle has chosen an hybrid approach: maintain the In-Memory Column Store in addition of the buffer cache. Dont’ forget our In-Memory event, but for the moment, let’s try(…)

In-Memory OLTP: Hash and Range indexes

Since SQL Server 2014 CTP2, Microsoft has introduced a new kind of index which is the Range index. We have now two ways for indexing an In-Memory table: using either an Hash index or a Range index. These two indexes(…)

SQL Server Tips: How to know if In-Memory Feature is supported by your server?

A customer asks me, how to know if In-Memory Feature is supported by my SQL Server server? An easy way is to check the edition, version etc. but now, you have directly a property for that. On msdn(…)

ALTER TABLE INMEMORY

By Franck Pachot . In-Memory Column Store is amazing. It brings very good performance to full table scans. I’t easy: just ‘flip a switch’ and you accelerate all reporting queries on your table, without thinking about what to index(…)

Memory management, OOM issues with SQL Server 2014 In-memory OLTP

Last week I gave a workshop about SQL Server 2014 and the new features. The first day we worked on new In-memory OLTP and different topics such as the new internal storage, the new transaction processing behavior or the(…)

Oracle 12.1.0.2: Wait event histograms in μs

By Franck Pachot . When an Oracle Database spends a high percentage of its DB time in User I/O, I usually check the wait event histograms in order to see if the storage system is working well. But today,(…)

Beyond In-Memory, what’s new in 12.1.0.2 ?

By Franck Pachot . It’s just a patchset. The delivery that is there to stabilize a release with all the bug fixes. But it comes with a lot of new features as well. And not only the one that(…)