[SQL Server] EOMONTH - the last day of the month

[SQL Server] EOMONTH  - the last day of the month

From SQL Server 2012, EOMENTH system function can be used for getting the last day of the month containing a specified date.

Before SQL Server 2012
Script

-- Before SQL Server 2012.
DECLARE @DT VARCHAR(10);
SET @DT = '2019-02-20';

SELECT DATEADD(d, -1, DATEADD(m, 1, CONVERT(DATE, LEFT(@DT, 8) + '01'))) AS 'the last day of the month', 
       CONVERT(DATE, CONVERT(CHAR(8), @DT) + '01') AS 'the first day of the month'
GO

Result

Using EOMONTH
Script

-- Using EOMONTH Function
DECLARE @DT VARCHAR(10);
SET @DT = '2019-02-20';

SELECT EOMONTH(@DT) AS 'the last day of the month', 
       CONVERT(DATE, CONVERT(CHAR(8), @DT) + '01') AS 'the first day of the month'
GO

Result

References

• EOMONTH (Transact-SQL): https://docs.microsoft.com/en-us/sql/t-sql/functions/eomonth-transact-sql?view=sql-server-ver15