Who can foreach
This post is about the popular question "What collection can be used in foreach statement?" If you think that correct answer is IEnumerable, read this post :)
Null or NotNull
This topic is related to this question on StackOverflow.
Let's discover, what are CanBeNull or NotNull attributes? How do they work?
IndexOf with IEquatable
This topic started from question on StackOverflow:
different collections (Array and List) have different implementation of IList.IndexOf method.
Неизвестный T-SQL
Несколько редко используемых, но вполне полезных функций MSSQL. Если вы никогда не слышали о функциях CHOOSE, ROW_NUMBER, RANK, DENSE_RANK, FIRST_VALUE, LAST_VALUE, LAG, LEAD, PERCENTILE_CONT и PERCENTILE_DISC, то ниже вы узнаете, какие полезные вещи можно сделать их помощью. Так же, я покажу несколько примеров использования выражений OVER и PARTITION BY в оконных функциях.
Useful Constraints
Usually we use constraints to specify the allowable values for the columns in tables. And it works perfectly! But beyond that, constraints help query analyzer to generate more effective query plans. How does it work? Read below.