SQL Server

SQL Server

What is Hashing; using Modulus to partition data

Hopefully this post goes some way in helping the reader understand better what hashing, hash indexes are and the need for row chains with In-memory Tables (Hekaton) in SQL Server 2014 hash indexes. Purpose of hashing? Hashing can be used to index character data, instead of building an index on a varchar(50) column for example, […]

Creating a Uniform, Normal and Benford Law’s Distribution from Random Numbers in SQL Server

Creating test data we often utilise random numbers, within SQL Server we can use the RAND() function or NEWID(). This quick post shows you how to create three different distributions based on the set {1..9} – Uniform (evenly distributed), Normal (distributed about the mean) and Benford – distribution follows Benfords Law of Log10( 1 + […]

Reducing SQL Server IO and Access Times using Bloom Filters – Part 3 (Inserting Data)

Part 2 (Basics of the method in SQL Server) explained how to get data into a Bloom Filter structure, it now needs persisting. This post explains a method on how a Bloom Filter can be stored in a SQL Server database – I assume you have read Part 1 and Part 2 and understand about […]

Reducing SQL Server IO and Access Times using Bloom Filters – Part 2 (Basics of the method in SQL Server)

Part 1 addressed Bloom Filter Concepts, if you haven’t already done so its important to start there. In this post I will show the basics of how we set and query the bit array that holds our Bloom Filter structure. Step 1 – Hash the target Data element (key) Multiple hash functions are used over your […]

Reducing SQL Server IO and Access Times using Bloom Filters – Part 1 (Concepts)

Given a 10 million row table with a GUID as a primary key, we have a 50,000 row table that we want to look up to see if we have any matching rows and for those matching rows aggregate the data – lets assuming that 50% of the rows have a corresponding match – so […]

Celebrate the Anniversary of SQL Server 2012!

Here is the chance to win the sweepstakes  on the eve of SQL Server 2012 release 1st Anniversary. Here is the text from SQL Server blog:   This month, we are celebrating the one year anniversary of SQL Server 2012, and we’d like to give a little shout out to our community to say, “Happy […]

Erlang – Running Concurrent Queries against Microsoft SQL Server

Running Erlang on Windows, you can connect to Microsoft SQL Server using Erlang’s own ODBC application. It’s extremely easy and straightforward (example below), you can use a DSNless connection so you don’t even need to set up an entry through the Windows ODBC Data Source Administrator. 1 2 3 4 5 6 7 8 9 […]