SQL SERVER中强迫类型转换cast和convert的区分详解

select CAST(‘123’ as int) — 123
select CONVERT(int, ‘123’) — 123

select CAST(123.4 as int) — 123
select CONVERT(int, 123.4) — 123

select CAST(‘123.4’ as int)
select CONVERT(int, ‘123.4’)
— Conversion failed when converting the varchar value ‘123.4’ to data type int.

select CAST(‘123.4’ as decimal) — 123
select CONVERT(decimal, ‘123.4’) — 123

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(20), @Num, 0) — 1234.56
select CONVERT(varchar(20), @Num, 1) — 1,234.56
select CONVERT(varchar(20), @Num, 2) — 1234.5600