TSQL code that causes table data to be deleted rather than fail with a compilation error

Question

Afternoon,
I recently did this by accident and it felt as though it should have failed with a compilation error rather than run
A query of the form
delete from jobs
where id in
select id from calibrations
will delete all rows in the jobs table when the id column exists in the jobs table, but not the calibrations table. This should fail with a compilation error.
the following sql can be used to generate a test database to show the problem
USE [test]
GO
/****** Object:  Table [dbo].[calibrations]    Script Date: 28/11/2014 13:32:59 ******/
SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO
CREATE TABLE [dbo].[calibrations](
    [JobId] [int] NULL,
    [textfield] [nvarchar](50) NULL
) ON [PRIMARY]
GO
/****** Object:  Table [dbo].[jobs]    Script Date: 28/11/2014 13:32:59 ******/
SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO
CREATE TABLE [dbo].[jobs](
    [Id] [int] NOT NULL,
    [Name] [nchar](10) NULL
) ON [PRIMARY]
GO
INSERT [dbo].[calibrations] ([JobId], [textfield]) VALUES (1, N'something')
GO
INSERT [dbo].[jobs] ([Id], [Name]) VALUES (1, N'a         ')
GO
INSERT [dbo].[jobs] ([Id], [Name]) VALUES (2, N'b         ')
GO
INSERT [dbo].[jobs] ([Id], [Name]) VALUES (3, N'c         ')
GO
INSERT [dbo].[jobs] ([Id], [Name]) VALUES (4, N'd         ')
GO
INSERT [dbo].[jobs] ([Id], [Name]) VALUES (5, N'e         ')
GO
INSERT [dbo].[jobs] ([Id], [Name]) VALUES (6, N'f         ')
GO
Simon
simon

Answer 1

will delete all rows in the jobs table when the id column exists in the jobs table,
but not the calibrations table. This should fail with a compilation error.
Hello Simon,
That's a bug in your T-SQL Statement, not in SQL Server. The Statement as it is valid and column "id" exists, so why should it fail on compilation?
And that is the reason why we always should use full qualified object name, e.g. like
delete from jobs AS J
where J.id in
select SUB.id from calibrations AS SUB
and this Statement should fail on compilation.
Olaf Helper
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