Triggers to insert the record in a table

Question

I have two table 1. Holiday 2. Attendance.
When I insert the record    in holiday table for his
 advance holiday   with empid, the same time I want to insert it attendance table
 automatically for the same date using a trigger
Insert into attendance (empid,date,holiday) values (20078,07/10/2014,1). If holiday column value 1 represent holiday marked,
 0 represent  holiday not marked. The same thing can happen vice versa
If employee mark his current attendance as  holiday through attendance,
 it should   be  inserted into holiday table 
automatically using triggers.
Insert into  Holiday (empid,date,holiday) values (20078,06/08/2014,1). If holiday column value 1 represent holiday marked,
 0 represent  holiday not marked. The same thing can happen vice versa
Please I am looking for your help , how I can make it using triggers 
to insert both table  in two different ways of options.
Regards
Pol
polachan

Answer 1

Hi polachan,
According to your description, if you want to synchronize the data between the holiday table and the attendance table while inserting records into holiday table, you need to create a trigger on the holiday table, please try the following syntax.
use <databasename>
go
create trigger Tr_holiday
on holiday
for insert
as
declare @empid varchar(20),
@date datetime,
@holiday int
select @empid = empid, @date=date, @holiday=holiday from inserted
declare @qty int
select @qty =count(*) from attendance where empid=@empid and date=@date and holiday=@holiday
if @qty<1
begin
insert into attendance
select i.empid,
i.date,
i.holiday
from inserted i
end
Meanwhile, if you want to insert the record into the holiday table when holiday is updated to 1 in the attendance table, you need to create another trigger on the attendance table, please try the following syntax.
use <databasename>
go
create trigger Tr_attendance
on attendance
for update
as
declare @holiday int
if update (holiday)
begin
select @holiday=holiday from inserted
if @holiday=1
begin
insert into dbo.holiday
select empid,
date,
holiday
from inserted
end
end
For more details about creating triggers in SQL Server, please review this article:
CREATE TRIGGER (Transact-SQL).
Thanks,
Lydia Zhang