SQL Server has a bunch of functions that return the current date/time. Two of these are the GETDATE() and SYSDATETIME() functions.
At first glance, these two functions appear to do the same thing – get the current date and time from the operating system of the computer on which the instance of SQL Server is running.
However, there’s a subtle difference between the two.
In SQL Server, just as you can use T-SQL to get the month name from a date, you can also use the same methods to get the day name. By day name, I mean Monday or Tuesday for example, and not the date number or number of the day of the week (which you can also get if you need it).
Here are three ways to return the day name from a date in SQL Server using T-SQL.
When using SQL Server, you have a few different options when you need to return the month name from a date using T-SQL. By month name, I’m not talking about the month number (such as 07). I’m talking about the full name of the month (such as July).
For example, when given a date of 2018-07-01, you want July to be returned.
This article presents three ways to return the month name from a date in SQL Server using T-SQL.
When you connect to SQL Server, usually the date format is determined by your language. The default language for a session is the language for that session’s login, unless overridden on a per-session basis by using the Open Database Connectivity (ODBC) or OLE DB APIs.
The date format setting affects the interpretation of character strings as they are converted to date values for storage in the database. It does not affect the display of date data type values that are stored in the database or the storage format.
Despite the fact that the your session’s language determines the date format, you can override the date format if required. For example, if your language is us_english, the date format will be mdy (so that 07/01/2018 represents the 1st of July and not the 7th of January). You can change this so that the date format is dmy (or any other format) while the language remains us_english.
You can use T-SQL to explicitly set the date format of the current session by using the SET DATEFORMAT statement.
When using SQL Server, your current connection includes a number of options that determine things like the language, date formats, etc. These could be set at whatever the default is, but they can also be overridden during the session by using a SET statement.
The date format affects the interpretation of character strings as they are converted to date values for storage in the database. When the language is set using SET LANGUAGE, the date format setting is implicitly set accordingly. This can be explicitly overridden with the SET DATEFORMAT statement.
In any case, you can find the current date format by using the DBCC USEROPTIONS command. This command returns the SET options that have been set for the current connection.
When working with dates in SQL Server, it’s easy to get tripped up with different date formats. For example, someone from the US might consider 01/07/2018 to mean the 7th of January, but someone from the UK might consider it to mean the 1st of July.
In many cases you might not even know which date format is used for any particular language/culture. Fortunately, SQL Server stores this information in its resource database, and you can retrieve it by using either of the two methods below.
If you need to convert a string into a date/time value in SQL Server, you have a number of options. In this post I outline six T-SQL functions that allow you to do this.
The six functions are:
CAST()CONVERT()PARSE()TRY_CAST()TRY_CONVERT()TRY_PARSE()Below are example of how you can use these functions to convert a string to a date/time data type.
If you work with SQL Server, chances are you’ve used at least one of the CONVERT() or CAST() functions to convert from one data type to another. If you’ve ever encountered an error while trying to convert a string to a date/time data type, the PARSE() function could be what you need.
For example, if you have a string like say, Fri, 20 Jul 2018, the CONVERT() or CAST() functions will throw an error. But the PARSE() function will handle it without a problem.
The PARSE() function returns the result of an expression, translated to the requested data type in SQL Server. So you can use it to “translate” your string value into a date/time data type (such as date, datetime, datetime2, etc).
When using SQL Server, you can convert a date/time value into a string by using the CONVERT() function. This function allows you to convert between different data types.
In this article, we’ll be converting between various date/time data types to a varchar or nvarchar string.
One of the good things about this function is that it allows you to specify the style that the date will be returned in. For example, you can specify whether it’s returned as mm/dd/yyyy, yyyy.mm.dd, Mon dd, yyyy, etc. You can also specify whether the time component is returned and how it’s styled.
The CONVERT() function allows you to convert between data types. It’s similar to the CAST() function, but one of the benefits of CONVERT() is that, when you convert from a date/time data type to a string, you can add an optional argument that specifies the style that you want the return value to be in. For example, you can have it returned as dd.mm.yyyy, yyyy-mm-dd, dd mon yyyy, etc
This article contains examples of the various styles you can return when converting a date/time value to a string using the CONVERT() function in SQL Server.