The difference between cast and convert forced type conversions in SQL Server

In SQL Server, both the cast and CONVERT functions are available for type conversions, and their functions are the same.

It's just a different syntax.

Cast is generally easier to use, and the advantage of convert is that dates and values can be formatted.

1 Select CAST('123'  as int)--1232 Select CONVERT(int,'123')--1233 4 Select CAST(123.4  as int)--1235 Select CONVERT(int,123.4)--1236 7 Select CAST('123.4'  as int)8 Select CONVERT(int,'123.4')9 --Conversion failed when converting the varchar value ' 123.4 ' to data type int.Ten  One Select CAST('123.4'  as decimal)--123 A Select CONVERT(decimal,'123.4')--123 -  -  the Select CAST('123.4'  as decimal(9,2))--123.40 - Select CONVERT(decimal(9,2),'123.4')--123.40 -  -  + Declare @Num  Money - Set @Num = 1234.56 + Select CONVERT(varchar( -),@Num,0)--1234.56 A Select CONVERT(varchar( -),@Num,1)--1,234.56 at Select CONVERT(varchar( -),@Num,2)--1234.5600

Convert is generally used in time conversion because it adds a style to the cast and can be converted to a different time format

CONVERT (data_type (length),data_to_be_converted,style)

data_type (length) Specifies the target data type (with optional lengths). The data_to_be_converted contains values that need to be converted. style Specifies the date/time output format.

The style value that can be used:

1 CONVERT(VARCHAR( +),GETDATE())2 CONVERT(VARCHAR(Ten),GETDATE(), the) 3 CONVERT(VARCHAR( One),GETDATE(),106)4 CONVERT(VARCHAR( -),GETDATE(),113)

The difference between cast and convert forced type conversions in SQL Server