Question

I am trying to populate the records from table1 to table2. table1 has three columns and no primary key. Table2 has three same columns with an identity column as a primary key. Following are my query and definitions. But somehow I got an error, Cannot insert the value NULL into column ‘notes_id’, table ‘table1; column does not allow nulls. INSERT fails.
The statement has been terminated.
What do I miss?

CREATE TABLE [dbo].[table1](
    [notes_id] [int] NOT NULL,
    [acty_id] [varchar](80) NOT NULL,
    [notes_datetime] [datetime] NOT NULL,
    [notes_data] [nvarchar](max) NULL,
 CONSTRAINT [PK_tblSRMNotes] PRIMARY KEY CLUSTERED 
(
    [notes_id] ASC
)WITH (PAD_INDEX  = OFF, STATISTICS_NORECOMPUTE  = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS  = ON, ALLOW_PAGE_LOCKS  = ON) ON [PRIMARY]
) ON [PRIMARY]

CREATE TABLE [dbo].[table2](
    [acty_id] [varchar](80) NOT NULL,
    [notes_datetime] [datetime] NOT NULL,
    [notes_data] [nvarchar](max) NULL
) ON [PRIMARY]

insert into table1(acty_id, notes_datetime, notes_data)
    select s.acty_id, s.notes_datetime, s.notes_data
    from table2 s 

Answer 1

You’ve set the first column to NOT NULL, and declared it as the PRIMARY KEY, but you haven’t indicated how it should be populated. Typically this is through an IDENTITY column:

CREATE TABLE [dbo].[table1]
(
    [notes_id] [int] IDENTITY(1,1) NOT NULL,
---------------------^^^^^^^^^^^^^
    [acty_id] [varchar](80) NOT NULL,
    [notes_datetime] [datetime] NOT NULL,
    [notes_data] [nvarchar](max) NULL,
    CONSTRAINT [PK_tblSRMNotes] PRIMARY KEY CLUSTERED (notes_id)
);