How to loop over table variable to make specific calculations? - sql

Question

If i have a table variable like that how to loop over this var to make some processing :
DECLARE #userData TABLE(
userId int NOT NULL,
dayDate datetime NOT NULL,
transIn datetime NULL,
transOut datetime NULL,
attIn datetime NULL,
attOut datetime NULL,
MissionIn datetime NOT NULL,
MissionOut datetime NOT NULL,
empState varchar(10) NULL
);
INSERT INTO #userData
SELECT userid, trans_date,transtime_in,transtime_out,att_start_time,att_end_time,#Mission_fromdatetime,#Mission_todatetime,day_flag
FROM datatable_o a
WHERE a.userid = #userid AND a.trans_date = #date ORDER BY transtime_in ;
According to the comments the Whole case :
If the work starts at : att_start_time and ends at att_end_time (work period]
Every employee could check -in and check-out many times in the same date so we could follow him .
the check-in stored in transtime_in
and check-out stored in transtime_out
and i have day_flag so i could know the day is 'W' work day or 'E' weekend
Now considering all these information in addition to the emp_num ,date
I want to calc for the an employee External mission over time :
I have four cases :
No check-in-out && Not work day [weekend] So the employee
should take all the mission period as overtime
No check-in-out && Work day [Absent] so the employee should
take only the mission period out of the work period
There are check-in-outs && Not work day [week end] so the
employee should take only the mission period out of these
check-ins-outs
There are check-ins-outs && work day so the employee should take
only the mission period out of these check-ins-outs and at the same
time out of work period .
Example :
emp_num date att_start att_end mission-in mission-out
672 2015-3-4 07:05:00 13:30:00 12:12:00 20:00:00
emp_num date trans_in trans_out
672 2015-3-4 06:54:00 11:10:00
672 2015-3-4 12:00:00 14:05:00

Answer 1

You can loop through your table by taking help from a copy of that table:
with regard to your question assuming your table is:
DECLARE #userData TABLE(
userId int NOT NULL,
/*Other fields*/
);
and the data of your table is:
INSERT INTO #userData
/*A SELECT or values*/
now create a copy of your table as:
DECLARE #userData_2 TABLE(
userId int NOT NULL,
/*Structure should be the same as #userData*/
);
INSERT INTO #userData_2
SELECT * FROM #userData
now you can do the loop and do whatever you want:
DECLARE #userId INT
WHILE EXISTS (SELECT * FROM #userData_2)
BEGIN
SET #userId=(SELECT TOP 1 userId FROM #userData)
/*
DO YOUR TRANSACTION HERE
*/
DELETE FROM #userData_2 WHERE userId=#userID
END
NOTICE: this assumes the userId is unique, if not then you need to have a unique field, or use a composite fields instead of userId.