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.
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.
In SQL Server, you can use use the CONVERT() function to convert a date value from one date data type to another (or between any other data type for that matter). However, that’s not the only function in the T-SQL toolbox for converting between data types.
The CAST() function is part of the ANSI SQL standard, and it does most of the things CONVERT() does. So in many cases, you have the option of which of these functions you prefer to use.
Many database professionals prefer CAST() due to the fact that it’s part of the ANSI SQL standard, however, others prefer CONVERT() due to the extra functionality that T-SQL’s implementation offers (such as being able to provide a date style).
In any case, this article provides examples of converting between different date formats using CAST().
Sometimes when working with databases and other programming environments, you get a date value but it’s in the wrong format/data type. For example, if a date has been generated with an inbuilt date function, it might include both the date and the time, right down to the last nanosecond. And all you want is the day, month, and year, say like this: 2018-01-01.
If this happens while you’re using SQL Server, you can use the CONVERT() function to convert it to another data type. When you do this, the data type will determine the format it appears as.
This article provides examples of using the CONVERT() function in SQL Server to convert a date value to another (date) data type.
In SQL Server, you can use the CAST() function to convert an expression of one data type to another. This function works almost the same as the CONVERT() function, except that the syntax is slightly different (and CAST() doesn’t accept the style argument).
So if you need to convert a string to a date/time value, you can use the CONVERT() function or the CAST() function.
And if you get an error while using those two functions, the PARSE() function might be just what you need.
This article contains examples using the CAST() function.