We store a wide variety of data within our platforms, some of which will inevitably be string based. Along with that comes a need to perform manipulation of those strings. When slicing, combining, or manipulating strings one element which we need to consider is the length of the string. Here I wanted to have a […]
When writing functions within SQL Server we sometimes have need to repeat an action multiple times until a given condition is met – also known as Recursion. There are a couple of common ways which this can be implemented which also have their different limitations. A little about recursion Firstly, why do we need recursion? […]
When designing a data schema to store a variety of entities it can be common to require a selection of flags to be stored. There are different ways in which the data can be designed to accommodate this which I wanted to look at here. Examples of these fields could be an ‘Is Active’ flag […]
When processing data there is frequently a need to rank the outputs. This could be to limit a selection of records to return, or provide a type of leader-board for reporting. There are a number of ranking functions within the SQL language which we’ll look at here with examples and outputs. We’ll start with some […]
When outputting data through a procedure it’s a common use case to add fields which have been calculated from existing data. One way to achieve this is using the CASE statement, however we don’t always need that level of complexity, particularly when we’re looking for a binary result such as ‘Yes’ / ‘No’. An alternative […]
Last time out we looked at how data can be persisted even with a ROLLBACK being executed. Here we’re going to take that and look at an example of using it in action. We’ll generate some data – which may be good or bad – and try to add it to a table. If there’s any bad data […]
Last week we started to at the use of constraints to support with data integrity in our databases. As a refresher on our introduction from last time: Data integrity helps give us assurance that our data is accurate, complete, and free from errors or inconsistencies. Some of this comes from making sure that data is correct […]
Data integrity helps give us assurance that our data is accurate, complete, and free from errors or inconsistencies. Some of this comes from making sure that data is correct before it enters are databases, but there are some tools we have in our databases which can help with this too – Constraints! Before we jump […]
When creating items in SQL Server we aren’t able to create multiple with the same name, for example two tables named dbo.Sales. Similarly we couldn’t create a table and view with the same name. However it isn’t the case that everything we create within a database has to be named uniquely. It can depend on […]
We’ve previously looked at how to implement vertical partitioning and the benefits it can bring within our data. Here I’d like to dive a little further into improving the performance even further with a couple of modifications to our schema. We’ll use the same setup as we had previously to create the table, populate it and partition it. This results in […]
Andy Brownsword 