SQL - 根据另一个表条目将新行插入现有表

Question

I have a company table and a licence table. I need to insert a new row in the license table for every company in the company table that isn't already in the license table.

License (ID,CompanyID,LicenseStart,LicenseEnd,CreatedDate,AddUser,UpdateUser,UpdateDate,TemplateId) The ID in this table is incremented by 1 when a new row is added.

Company (ID,Name,CreateDate,CState,LocationID,LegalName)

The default value that would be entered for each CompanyID that isn't already in the license table should look something like this.

Insert (ID, @theCompanyID, GetDate(), DATEADD(day,14,GETDATE()), null,null,null,null null)

@theCompanyID would be the CompanyID that isn't in the license table

I am very new to this so any help would be appreciated.

Answer 1

license.id is an identity column, so you do not need to insert it.

insert into license (CompanyID, LicenseStart, LicenseEnd)
    select c.id, GetDate(), DATEADD(day, 14, GETDATE())
    from company c
    where not exists (select 1
                      from license l
                      where c.ID = l.CompanyID
                     );

You also don't need to insert explicit NULL values for columns where you are not supplying values. The default is to set these values to NULL .

If your start and end dates do not have a time component -- just the date -- then use this instead:

    select c.id, cast(GetDate() as date), cast(DATEADD(day, 14, GETDATE()) as date)
    from company c
    where not exists (select 1
                      from license l
                      where c.ID = l.CompanyID
                     );

Answer 2

Do an INSERT with SELECT , use NOT EXISTS to make sure no existing company is inserted again. Something like:

insert into license (ID,CompanyID,LicenseStart,LicenseEnd,CreatedDate,AddUser,UpdateUser,UpdateDate,TemplateId)
select ID, theCompanyID, GetDate(), DATEADD(day,14,GETDATE()), null,null,null,null null
from company
where not exists (select 1 from company
                  where company.CompanyID = license.CompanyID)

Answer 3

INSERT INTO License (CompanyID, LicenseStart, LicenseEnd)
SELECT ID, GetDate(), DATEADD(day,14,GETDATE())
FROM Company
WHERE ID NOT IN
(
    SELECT DISTINCT CompanyID
    FROM License
)

Answer 4

You can do it with LEFT JOIN :

INSERT  INTO License
        ( CompanyID ,
          LicenseStart ,
          LicenseEnd ,
          CreatedDate ,
          AddUser ,
          UpdateUser ,
          UpdateDate ,
          TemplateId
        )
        SELECT  ID ,
                GETDATE() ,
                DATEADD(DAY, 14, GETDATE()) ,
                NULL ,
                NULL ,
                NULL ,
                NULL ,
                NULL
        FROM    Company c
                LEFT JOIN License l ON l.CompanyID = c.ID
        WHERE   l.ID IS NULL

Answer 5

An alternative way to do is to use the EXCEPT operator which is faster than subquery or join owing to it being a set function.

Insert License

select a.CompanyID, GetDate(), DATEADD(day,14,GETDATE()), null,null,null,null null
from 
    (select id from company 
    except
    select CompanyID from License
    )a

Answer 6

Since OP has said that the ID in the license table is incremented by 1 then you can write your query like this:

INSERT INTO License(CompanyID,LicenseStart,LicenseEnd)
SELECT c.ID, GetDate(), DATEADD(day,14,GETDATE()))
FROM Company c
WHERE NOT EXISTS
(
    SELECT l.CompanyID
    FROM License l
    WHERE l.CompanyID = c.ID
)

You do not have to specify the column in the INSERT statement if the column is automatically incremented. Also I chose to use NOT EXISTS instead of NOT IN in the `WHERE clause for the reason that Martin Smith specified in this Stack Overflow question .