Posts

SQL Server vs .NET DateTime Leap Year Arithmetic

I recently refactored some code that was performing date arithmetic in SQL Server. The code was attempting to retrieve the "same day next year" by adding 365 days to the date provided. I was refactoring this logic out of SQL Server and in to .NET, and I was concerned that .NET's DateTime arithmetic wouldn't match SQL Server. I was pleasantly surprised that the results were the same. However, I should call out that perhaps in your situation adding 365 days to a given date is not appropriate for getting the "same day next year" value. I also compared this logic when preforming a "Add years + 1" and the results were also the same. (However, to be clear, adding 365 days differed from adding 1 year, but both SQL and .NET preformed the same given the method used.) source code:  https://gist.github.com/aaronhoffman/3d997390dab7f69e6597 results table: Method Value StartDate .NET Result SQL Result AddDays 365 2/27/2011 2/27/2012 2/27/2012 AddYears

Generate SQL Statements to Group By Each Column of Table Separately

When working with data with the intent to visualize, there are times when I'll want to group by every column in a table, separately, one at a time, to determine the possible values in that column. I do this often enough I created a simple SQL Query to build these group by statements for me: declare @table_name varchar(200) = 'dbo.mytablename' select 'select ' + c.name + ', count(1) cnt from ' + @table_name + ' group by ' + c.name + ' order by 2 ' from sys.columns c where c.object_id = object_id(@table_name) gist:  https://gist.github.com/aaronhoffman/d49d3705fd716b0fe6cb Hope this helps, Aaron

ASP.NET MVC 5 Identity, Users, Roles, Accounts, SQL to Generate Tables

In ASP.NET MVC 5, user management changed significantly from ASP.NET MVC 4. This is the start of a series of blog posts on the topic (long overdue). This post is on the SQL that your website executes to initially create the identity (user, role) tables. The SQL the ApplicationUserManager and ApplicationSigninManager generate and execute is below: CREATE TABLE [dbo].[AspNetRoles] (     [Id] [nvarchar](128) NOT NULL,     [Name] [nvarchar](256) NOT NULL,     CONSTRAINT [PK_dbo.AspNetRoles] PRIMARY KEY ([Id]) ) go CREATE TABLE [dbo].[AspNetUserRoles] (     [UserId] [nvarchar](128) NOT NULL,     [RoleId] [nvarchar](128) NOT NULL,     CONSTRAINT [PK_dbo.AspNetUserRoles] PRIMARY KEY ([UserId], [RoleId]) ) go CREATE TABLE [dbo].[AspNetUsers] (     [Id] [nvarchar](128) NOT NULL,     [Email] [nvarchar](256),     [EmailConfirmed] [bit] NOT NULL,     [PasswordHash] [nvarchar](max),     [SecurityStamp] [nvarchar](max),     [PhoneNumber] [nvarchar](max),     [PhoneNumber