Querying 3 tables where I'm looking for non-matches - sql-server

Question

I have three tables: LitHold, LitHoldDetails and EmailTemplate. The definitions are as follows.
CREATE TABLE [dbo].[LitHold](
[LitholdID] [int] IDENTITY(1,1) NOT NULL,
[LitHoldStatusID] [tinyint] NOT NULL,
[EmailReminderID] [tinyint] NULL,
[ApprovedDate] [datetime] NULL,
[TerminatedDate] [datetime] NULL,
CONSTRAINT [PK_Lithold] PRIMARY KEY CLUSTERED
(
[LitholdID] 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].[LitHoldDetails](
[LitHoldDetailsID] [int] IDENTITY(1,1) NOT NULL,
[LitholdID] [int] NOT NULL,
[VersionID] [int] NOT NULL,
[Description] [varchar](300) NULL,
[ResAttorneyID] [varchar](10) NOT NULL,
[Comments] [varchar](1000) NULL,
[HoldStartDate] [datetime] NULL,
[HoldEndDate] [datetime] NULL,
[CreatedDate] [datetime] NOT NULL,
[CreatedByLogin] [varchar](10) NULL,
CONSTRAINT [PK_LitholdDetails] PRIMARY KEY CLUSTERED
(
[LitHoldDetailsID] 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].[EmailTemplate](
[TemplateID] [int] IDENTITY(1,1) NOT NULL,
[LitHoldDetailsID] [int] NOT NULL,
[From] [varchar](50) NULL,
[To] [varchar](2000) NULL,
[CC] [varchar](500) NULL,
[BCC] [varchar](500) NULL,
[Subject] [nvarchar](200) NULL,
[MessageBody] [nvarchar](max) NULL,
[SendDate] [datetime] NULL,
[IsDefault] [bit] NOT NULL,
CONSTRAINT [PK_EmailTemplate] PRIMARY KEY CLUSTERED
(
[TemplateID] ASC
)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]
) ON [PRIMARY]
For each LitHold, there can be multiple LitHoldDetails. For each LitHoldDetail, there should be one EmailTemplate. I recently found that some LitHoldDetails do NOT have EmailTemplates. We're still working in development on this project, so this isn't a big deal. However, we want to get the EmailTemplate data into the database. The situation is that for each LitHold, there is at least one LitHoldDetail that has an EmailTemplate. I would like to duplicate this EmailTemplate data for all the LitHoldDetails that a) have the same LitHoldID and b) do not have an EmailTemplate. One of the approaches I've tried is:
insert into EmailTemplate
(LitHoldDetailsID, [From], [To], CC, BCC, Subject, MessageBody, SendDate, IsDefault)
(select (select top 1 LitHoldDetailsID from LitHoldDetails where LitholdID = d.LitholdID and LitHoldDetailsID <> e.LitHoldDetailsID), [To], CC, BCC, Subject, MessageBody, SendDate, IsDefault from
EmailTemplate e inner join LitHoldDetails d on e.LitHoldDetailsID = d.LitHoldDetailsID)
but this gets me multiple rows for some LitHoldDetails, with different EmailTemplate data, and some rows where LitHoldDetails is NULL. How can I accomplish this? I'm using SQL Server 2008.

Answer 1

Try inserting this:
SELECT lhd.LitHoldDetailsID, CloneEmailTemplate.[From], ...
FROM LitHoldDetails lhd
CROSS APPLY (SELECT TOP 1 et.*
FROM EmailTemplate et
JOIN LitHoldDetails lhd2 ON lhd2.LitHoldDetailsID = et.LitHoldDetailsID
WHERE lhd2.LitHoldID = lhd.LitHoldID
) AS CloneEmailTemplate
WHERE NOT EXISTS (SELECT 1
FROM EmailTemplate et2
WHERE et2.LitHoldDetailsID = lhd.LitHoldDetailsID
)